Nodo Sistema De Comercio Js

Utilizamos Node para informar, pero no como parte de nuestro principal sistema generador de señales. Para ser honesto, la respuesta será casi seguro que sí para cada tecnología de programación común, ya que sólo se necesita una persona para utilizarlo en algún lugar para hacer la respuesta sí. Basta con echar un vistazo a OCaml, antes de Jane Street, la mayoría de techno logiest en la calle nunca había oído hablar de él y ahora es muy conocido. Probablemente la respuesta canónica para este tipo de pregunta debería ser ésta: quant. stackexchange / a / 304/743 META RANT En general, encuentro este tipo de preguntas un poco problemáticas para este sitio por dos razones: para cualquier lenguaje de programación o pila Si usted pide es cualquier persona que usa esto para negociar la respuesta es probablemente probable sí. No hay ningún resultado o llamado real a la acción de la pregunta. Si alguien responde sí, ¿qué pasa si alguien responde no, así que ¿Cuál es la respuesta canónica a una pregunta como esta que O decir de otra manera, qué respuesta haría que el póster feliz aquí respondió Jun 11 14 at 14: 52Automated Trading System in Node. js Registrado el: 15 de agosto de 2015 Lengua favorita: JavaScript Top 3 idiomas: JavaScript CC Otros Años de experiencia en programación: 10 Línea de código favorita: for i in seq 10 do docker run - d - e DOCKERHOSTIPquot172.17.42.1quot container ampamp Sleep 2 done IDE favorito: vim Ciudad: (No especificado) País: Estados Unidos Mi sitio web: gitlord Idiomas Quiero aprender: JavaScript CC Otros Únete a mí chat. gitlord ¿Qué Linux estoy usando ¿Qué gestor de ventanas / entorno de escritorio? Es este proyecto sobre sistemas de diseño y escritura para el comercio automatizado de acciones, opciones y FOREX. ¿Por qué el infierno iba a utilizar Node. js un caso por caso Introducción JavaScripts creciente popularidad ha traído consigo una gran cantidad de cambios, y la cara del desarrollo web de hoy es dramáticamente diferente. Las cosas que podemos hacer en la web hoy en día con JavaScript que se ejecuta en el servidor, así como en el navegador, eran difíciles de imaginar hace sólo varios años, o fueron encapsulados en entornos de caja de seguridad como Applets Flash o Java. Antes de excavar en Node. js. Es posible que desee leer sobre las ventajas de usar JavaScript en la pila que unifica el idioma y el formato de datos (JSON), lo que le permite optimizar la reutilización de los recursos del desarrollador. Como esto es más un beneficio de JavaScript que de Node. js específicamente, no lo discutiremos mucho aquí. Pero es una ventaja clave para incorporar Node en tu stack. Como Wikipedia dice: Node. js es una compilación empaquetada del motor JavaScript de Googles V8, la capa de abstracción de la plataforma libuv y una librería central, que está escrita principalmente en JavaScript. Más allá de eso, vale la pena señalar que Ryan Dahl, el creador de Node. js, tenía como objetivo crear sitios web en tiempo real con capacidad de empuje. Inspirado en aplicaciones como Gmail. En Node. js, le dio a los desarrolladores una herramienta para trabajar en el paradigma de E / S sin bloqueo, impulsado por eventos. Después de más de 20 años de apátridas-web basado en el paradigma de solicitud-respuesta sin estado, finalmente tenemos aplicaciones web con conexiones bidireccionales en tiempo real. En una frase: Node. js brilla en aplicaciones web en tiempo real que emplean tecnología push a través de websockets. Bueno, después de más de 20 años de apátridas basado en el paradigma de solicitud-respuesta sin estado, finalmente tenemos aplicaciones web con conexiones bidireccionales en tiempo real, donde tanto el cliente como el servidor pueden iniciar la comunicación, Permitiéndoles intercambiar datos libremente. Esto está en marcado contraste con el típico paradigma de respuesta web, donde el cliente siempre inicia la comunicación. Además, todo está basado en la pila web abierta (HTML, CSS y JS) que se ejecuta sobre el puerto estándar 80. Uno podría argumentar que hemos tenido esto durante años en forma de Applets Flash y Java, pero en realidad, La web como un protocolo de transporte para ser entregado al cliente. Además, se ejecutaban en aislamiento ya menudo operaban sobre puertos no estándar, lo que puede haber requerido permisos adicionales y tal. Con todas sus ventajas, Node. js ahora juega un papel crítico en la pila de tecnología de muchas empresas de alto perfil que dependen de sus beneficios únicos. En este post, discutiré no sólo cómo se logran estas ventajas, sino también por qué es posible que desee utilizar Node. jsand por qué no usar algunos de los modelos clásicos de aplicaciones web como ejemplos. Cómo funciona La idea principal de Node. js: utilizar E / S sin bloqueo y eventos para mantenerse ligero y eficiente frente a las aplicaciones en tiempo real que utilizan datos intensivos que se ejecutan a través de dispositivos distribuidos. Eso es un bocado. Lo que realmente significa es que Node. js no es una nueva plataforma de plata-bala que dominará el mundo del desarrollo web. En su lugar, es una plataforma que llena una necesidad particular. Lo que realmente significa es que Node. js no es una nueva plataforma de plata-bala que dominará el mundo del desarrollo web. En su lugar, es una plataforma que llena una necesidad particular. Y entender esto es absolutamente esencial. Usted definitivamente no quiere utilizar Node. js para las operaciones de uso intensivo de la CPU de hecho, el uso de él para el cálculo pesado anulará casi todas sus ventajas. Donde Node realmente brilla es en la construcción de aplicaciones de red rápidas y escalables, ya que es capaz de manejar un gran número de conexiones simultáneas con alto rendimiento, lo que equivale a una alta escalabilidad. Cómo funciona bajo el capó es bastante interesante. En comparación con las técnicas tradicionales de servicio web en las que cada conexión (petición) genera un nuevo subproceso, que ocupa la RAM del sistema y eventualmente maximiza la cantidad de RAM disponible, Node. js opera en un solo hilo, S, lo que le permite soportar decenas de miles de conexiones simultáneas (mantenidas en el bucle de eventos). Un cálculo rápido: suponiendo que cada hilo potencialmente tiene un acompañamiento de 2 MB de memoria con él, que se ejecuta en un sistema con 8 GB de RAM nos pone en un máximo teórico de 4000 conexiones simultáneas, además del costo de cambio de contexto entre hilos. Ese es el escenario que normalmente se ocupan en las técnicas tradicionales de servicio web. Al evitar todo esto, Node. js logra niveles de escalabilidad de más de 1 M conexiones concurrentes (como una prueba de concepto). Hay, por supuesto, la cuestión de compartir un único hilo entre todas las solicitudes de los clientes, y es una trampa potencial de escribir aplicaciones Node. js. En primer lugar, la computación pesada podría ahogar nodos de hilo único y causar problemas para todos los clientes (más sobre esto más adelante) como las solicitudes de entrada se bloqueó hasta que dicho cálculo se completó. En segundo lugar, los desarrolladores deben tener mucho cuidado de no permitir que una excepción borre hasta el bucle de eventos Node. js de núcleo (superior), lo que hará que la instancia de Node. js termine (bloqueando eficazmente el programa). La técnica utilizada para evitar las excepciones borboteando hasta la superficie es devolver errores al llamador como parámetros de devolución de llamada (en lugar de lanzarlos, como en otros entornos). Incluso si alguna excepción no tratada logra burbujear, existen múltiples paradigmas y herramientas disponibles para supervisar el proceso del nodo y realizar la recuperación necesaria de una instancia estrellada (aunque no será capaz de recuperar sesiones de usuarios), siendo el más común el módulo Forever . O un enfoque diferente con las herramientas del sistema externo upstart y monit. NPM: El gestor de paquetes de nodos Cuando se habla de Node. js, una cosa que definitivamente no se debe omitir es la compatibilidad integrada para la gestión de paquetes utilizando la herramienta NPM que viene por defecto con cada instalación de Node. js. La idea de los módulos de NPM es bastante similar a la de Ruby Gems. Un conjunto de componentes reutilizables disponibles públicamente, disponibles a través de una instalación fácil a través de un repositorio en línea, con administración de versiones y dependencias. Se puede encontrar una lista completa de los módulos empaquetados en el sitio web de NPM npmjs. org/. O se accede mediante la herramienta NPM CLI que se instala automáticamente con Node. js. El ecosistema de módulos está abierto a todos y cualquiera puede publicar su propio módulo que aparecerá en el repositorio de NPM. Una breve introducción a NPM (un poco antigua, pero aún válida) se puede encontrar en howtonode. org/introduction-to-npm. Algunos de los módulos NPM más populares de hoy son: express - Express. js, un framework de desarrollo web inspirado en Sinatra para Node. js, y el estándar de facto para la mayoría de las aplicaciones de Node. js que hay hoy en día. Connect - Connect es una estructura de servidor HTTP extensible para Node. js, proporcionando una colección de complementos de alto rendimiento conocidos como middleware que sirven como base de base para Express. Socket. io y sockjs - Componente del lado del servidor de los dos componentes websockets más comunes que existen hoy en día. Jade - Uno de los motores de plantillas más populares, inspirado en HAML, un valor predeterminado en Express. js. Mongo y mongojs - Envoltorios MongoDB para proporcionar la API para bases de datos de objeto MongoDB en Node. js. Redis - Redis biblioteca de clientes. Coffee-script - El compilador de CoffeeScript que permite a los desarrolladores escribir sus programas Node. js usando Coffee. Subrayado (lodash. Lazy) - La biblioteca de utilidades más popular en JavaScript, empaquetada para ser utilizada con Node. js, así como sus dos contrapartes, que prometen un mejor rendimiento tomando un enfoque de implementación ligeramente diferente. Forever - Probablemente la utilidad más común para asegurar que una secuencia de comandos de nodo dada se ejecute continuamente. Mantiene el proceso de Node. js en producción ante cualquier fallo inesperado. La lista continua. Hay toneladas de paquetes realmente útiles por ahí, disponibles para todos (sin ofender a los que he omitido aquí). Ejemplos de dónde debe usarse Node. js CHAT Chat es la aplicación más común en tiempo real y multiusuario. Desde IRC (en el día), a través de muchos protocolos propietarios y abiertos que se ejecutan en puertos no estándar, a la capacidad de implementar todo hoy en Node. js con websockets que se ejecutan sobre el puerto estándar 80. La aplicación de chat es realmente el dulce - Ejemplo de punto para Node. js: es una aplicación ligera, de alto tráfico, de datos intensivos (pero de bajo procesamiento / cálculo) que se ejecuta a través de dispositivos distribuidos. También es un gran caso de uso para aprender también, ya que es simple, pero cubre la mayoría de los paradigmas que usará en una aplicación típica de Node. js. Vamos a tratar de describir cómo funciona. En el ejemplo más simple, tenemos una única sala de chat en nuestro sitio web donde la gente viene y puede intercambiar mensajes de uno a muchos (en realidad todos) la moda. Por ejemplo, digamos que tenemos tres personas en el sitio web todas conectadas a nuestro foro de mensajes. En el lado del servidor, tenemos una simple aplicación Express. js que implementa dos cosas: 1) un manejador GET / request que sirve la página web que contiene tanto un tablero de mensajes como un botón Send para inicializar la entrada de nuevo mensaje, y 2) un websockets Servidor que escucha los nuevos mensajes emitidos por los clientes websocket. En el lado del cliente, tenemos una página HTML con un par de manejadores configurados, uno para el evento de clic de botón de envío, que recoge el mensaje de entrada y lo envía por el websocket, y otro que escucha los nuevos mensajes entrantes en el Cliente de websockets (es decir, mensajes enviados por otros usuarios, que el servidor ahora quiere que el cliente muestre). Cuando uno de los clientes envía un mensaje, heres lo que sucede: El navegador captura el botón Enviar clic a través de un controlador de JavaScript, recoge el valor del campo de entrada (es decir, el texto del mensaje) y emite un mensaje websocket con el cliente websocket conectado a Nuestro servidor (inicializado en la inicialización de página web). El componente del lado del servidor de la conexión websocket recibe el mensaje y lo reenvía a todos los demás clientes conectados mediante el método de difusión. Todos los clientes reciben el nuevo mensaje como un mensaje push a través de un componente websockets del cliente que se ejecuta dentro de la página web. A continuación, recoger el contenido del mensaje y actualizar la página web en el lugar mediante la adición del nuevo mensaje a la Junta. Este es el ejemplo más simple. Para una solución más robusta. Puede utilizar una caché simple basada en la tienda Redis. O en una solución aún más avanzada, una cola de mensajes para manejar el enrutamiento de mensajes a clientes y un mecanismo de entrega más robusto que puede cubrir pérdidas de conexión temporal o almacenar mensajes para clientes registrados mientras están desconectados. Sin embargo, independientemente de las mejoras que realice, Node. js seguirá funcionando bajo los mismos principios básicos: reaccionar a eventos, gestionar muchas conexiones simultáneas y mantener la fluidez en la experiencia del usuario. API ENCIMA DE UN OBJETO DB Aunque Node. js realmente brilla con aplicaciones en tiempo real, es bastante natural para exponer los datos de DB de objetos (por ejemplo, MongoDB). Los datos almacenados JSON permiten que Node. js funcione sin la diferencia de impedancia y la conversión de datos. Por ejemplo, si está utilizando Rails, debería convertir de JSON a modelos binarios y luego volver a exponerlos como JSON a través del HTTP cuando los datos son consumidos por Backbone. js, Angular. js, etc. o incluso llamadas jQuery AJAX normales. Con Node. js, simplemente puede exponer sus objetos JSON con una API REST para que el cliente consuma. Además, no necesita preocuparse por la conversión entre JSON y cualquier otra cosa cuando lea o escriba de su base de datos (si está usando MongoDB). En resumen, puede evitar la necesidad de múltiples conversiones utilizando un formato de serialización de datos uniforme en el cliente, el servidor y la base de datos. ENTRADAS QUEUAD Si está recibiendo una gran cantidad de datos concurrentes, su base de datos puede convertirse en un cuello de botella. Como se muestra arriba, Node. js puede manejar fácilmente las conexiones simultáneas. Pero como el acceso a la base de datos es una operación de bloqueo (en este caso), nos encontramos con problemas. La solución es reconocer el comportamiento de los clientes antes de que los datos se escriban realmente en la base de datos. Con ese enfoque, el sistema mantiene su capacidad de respuesta bajo una carga pesada, lo cual es particularmente útil cuando el cliente no necesita confirmación firme de la correcta escritura de datos. Ejemplos típicos incluyen: el registro o escritura de datos de seguimiento de usuarios, procesados ​​en lotes y no utilizados hasta un momento posterior, así como operaciones que no necesitan ser reflejadas instantáneamente (como actualizar un cuenta de Facebook en Facebook) donde la consistencia eventual Utilizado en el mundo NoSQL) es aceptable. Los datos se ponen en cola a través de algún tipo de almacenamiento en caché o de la infraestructura de cola de mensajes (por ejemplo, RabbitMQ, ZeroMQ) y se digieren mediante un proceso de batch-write de base de datos separado, o servicios de procesamiento de procesamiento intensivo de back-end escritos en una plataforma de mejor desempeño para tales tareas. Un comportamiento similar se puede implementar con otros lenguajes / frameworks, pero no en el mismo hardware, con el mismo alto y mantenido rendimiento. En pocas palabras: con Node, puedes empujar la base de datos escribe a un lado y tratar con ellos más tarde, procediendo como si tuvieran éxito. DATA STREAMING En las plataformas web más tradicionales, las solicitudes HTTP y las respuestas se tratan como un evento aislado de hecho, theyre realmente arroyos. Esta observación se puede utilizar en Node. js para crear algunas características interesantes. Por ejemplo, es posible procesar archivos mientras están siendo subidos, ya que los datos entran a través de un flujo y podemos procesarlo de una manera en línea. Esto podría hacerse para la codificación de audio o video en tiempo real. Y la representación entre diferentes fuentes de datos (ver sección siguiente). PROXY Node. js se emplea fácilmente como un proxy del lado del servidor donde puede manejar una gran cantidad de conexiones simultáneas de una manera no bloqueante. Su especialmente útil para la representación de diferentes servicios con diferentes tiempos de respuesta, o la recopilación de datos de múltiples puntos de origen. Un ejemplo: considere una aplicación del lado del servidor que se comunica con recursos de terceros, extrae datos de fuentes diferentes o almacena activos como imágenes y videos en servicios cloud de terceros. Aunque existen servidores proxy dedicados, el uso de Node puede resultar útil si su infraestructura de proxy es inexistente o si necesita una solución para el desarrollo local. Con esto, quiero decir que podría crear una aplicación de cliente con un servidor de desarrollo Node. js para los activos y las solicitudes API de proxy / stubbing, mientras que en la producción youd manejar dichas interacciones con un servicio de proxy dedicado (nginx, HAProxy, etc.) . BROKERAGE - STOCK TRADERS DASHBOARD Permite volver al nivel de aplicación. Otro ejemplo en el que domina el software de escritorio, pero que podría ser fácilmente reemplazado por una solución web en tiempo real es el software de comercio de corredores, utilizado para rastrear los precios de las acciones, realizar cálculos y análisis técnicos y crear gráficos. Cambiar a una solución basada en la web en tiempo real permitiría a los corredores cambiar fácilmente estaciones de trabajo o lugares de trabajo. Pronto, podríamos comenzar a verlos en la playa en la Florida. O Ibiza. O Bali. MONITORIZACIÓN DE LA APLICACIÓN DEL SALTO DE INSTRUMENTOS Otro caso de uso común en el que Node-with-web-sockets encaja perfectamente: seguimiento de los visitantes del sitio web y visualización de sus interacciones en tiempo real. (Si está interesado, esta idea ya está siendo producida por Hummingbird.) Usted podría reunir estadísticas en tiempo real de su usuario, o incluso moverlo al siguiente nivel mediante la introducción de interacciones específicas con sus visitantes mediante la apertura de un canal de comunicación cuando lleguen Un punto específico en su embudo. Imagínese cómo podría mejorar su negocio si supiera lo que sus visitantes estaban haciendo en tiempo real, si pudiera visualizar sus interacciones (si está interesado, esta idea ya está siendo producida por CANDDi). Con los sockets de Node. js de dos vías en tiempo real, ahora puede hacerlo. SISTEMA DE SEGUIMIENTO DEL TABLERO DE INSTRUMENTOS Ahora, vamos a visitar el lado de la infraestructura de las cosas. Imagine, por ejemplo, un proveedor de SaaS que desee ofrecer a sus usuarios una página de supervisión de servicios (por ejemplo, la página de estado de GitHubs). Con el bucle de eventos Node. js, podemos crear un potente panel de control basado en web que comprueba los estados de los servicios de forma asincrónica y empuja los datos a los clientes mediante websockets. Tanto los estados internos (intra-empresa) como los servicios públicos pueden ser reportados en vivo y en tiempo real utilizando esta tecnología. Empuje esa idea un poco más e intente imaginar las aplicaciones de monitoreo del Network Operations Center (NOC, por sus siglas en inglés) en un operador de telecomunicaciones, proveedor de cloud / network / hosting, o alguna institución financiera, todas ejecutadas en la web abierta respaldada por Node. js y websockets En lugar de Java y / o Applets Java. Nota: No trate de construir sistemas duros en tiempo real en Nodo (es decir, sistemas que requieran tiempos de respuesta consistentes). Erlang es probablemente una mejor opción para esa clase de aplicación. Donde se puede usar Node. js APLICACIONES WEB DEL SERVIDOR Node. js con Express. js también se puede usar para crear aplicaciones web clásicas en el servidor. Sin embargo, aunque sea posible, este paradigma petición-respuesta en el que Node. js llevaría alrededor de HTML representado no es el caso de uso más típico. Hay argumentos a favor y en contra de este enfoque. Aquí hay algunos datos a tener en cuenta: Si su aplicación no tiene ninguna CPU de computación intensiva, puede construir en Javascript de arriba a abajo, incluso hasta el nivel de base de datos si se utiliza el almacenamiento de objetos JSON DB como MongoDB. Esto facilita el desarrollo (incluyendo la contratación) de manera significativa. Los rastreadores reciben una respuesta HTML totalmente renderizada, que es mucho más SEO-friendly que, por ejemplo, una aplicación de página única o una aplicación de websockets ejecutada en la parte superior de Node. js. Cualquier CPU de computación intensiva bloqueará la capacidad de respuesta de Node. js, por lo que una plataforma de subprocesos es un enfoque mejor. Alternativamente, podría intentar escalar el cálculo. El uso de Node. js con una base de datos relacional es todavía bastante doloroso (ver más abajo para más detalles). Hágase un favor y recoja cualquier otro entorno como Rails, Django o ASP. Net MVC si está intentando realizar operaciones relacionales. Una alternativa a estos cálculos intensivos de CPU es crear un entorno de respaldo MQ altamente escalable con procesamiento back-end para mantener a Node como un empleado de cara al frente para manejar solicitudes de clientes de forma asíncrona. Donde Node. js Debe Utilizarse APLICACIÓN DEL WEB DEL SERVIDOR CON UN DB RELACIONAL DETRÁS Comparando Node. js con Express. js contra Ruby on Rails, por ejemplo, hay una decisión limpia a favor de este último cuando se trata de datos relacionales acceso. Las herramientas de DB relacionales para Node. js todavía están en sus primeras etapas, son bastante inmaduros y no son tan agradables de trabajar. Por otro lado, Rails automagically proporciona la configuración de acceso a datos justo fuera de la caja junto con las herramientas de soporte de migraciones de esquema de base de datos y otras joyas (juego de palabras). Rails y sus marcos de pares tienen maduras y probadas Active Record o Data Mapper implementaciones de capa de acceso a datos, que youll mucho falta si intenta replicar en JavaScript puro. Sin embargo, si usted es realmente inclinado a permanecer JS todo el camino (y listo para sacar un poco de su pelo), mantener un ojo en el Sequelize y nodo ORM2 ambos son inmaduros, pero pueden llegar a ponerse al día. Es posible y no es raro utilizar Node únicamente como front-end, manteniendo el back-end de Rails y su fácil acceso a un DB relacional. CÁLCULO / PROCESAMIENTO PESADO DEL SERVIDOR Cuando se trata de computación pesada, Node. js no es la mejor plataforma alrededor. No, definitivamente no quieres construir un servidor de computación Fibonacci en Node. js. En general, cualquier operación de uso intensivo de la CPU anula todos los beneficios de rendimiento que Node ofrece con su modelo de E / S sin bloqueo de eventos porque cualquier solicitud entrante se bloqueará mientras el subproceso está ocupado con su crujido de números. Como se indicó anteriormente, Node. js es de subproceso único y utiliza sólo un núcleo de CPU. Cuando se trata de agregar concurrencia a un servidor multi-core, el equipo principal del nodo realiza algún trabajo en forma de un módulo de clúster ref: nodejs. org/api/cluster. html. También puede ejecutar varias instancias de servidor Node. js muy fácilmente detrás de un proxy inverso a través de nginx. Con el uso de clústeres, debe descargar todos los cálculos pesados ​​a procesos de fondo escritos en un entorno más apropiado para ello y hacer que se comuniquen a través de un servidor de cola de mensajes como RabbitMQ. A pesar de que su procesamiento de fondo podría ser ejecutado en el mismo servidor inicialmente, tal enfoque tiene el potencial de escalabilidad muy alta. Esos servicios de procesamiento en segundo plano podrían distribuirse fácilmente para separar los servidores de los trabajadores sin necesidad de configurar las cargas de los servidores web frontales. Por supuesto, usará el mismo enfoque en otras plataformas también, pero con Node. js obtendrá un alto rendimiento de reqs / sec de que hemos hablado, ya que cada solicitud es una tarea pequeña manejada muy rápida y eficientemente. Conclusión Hemos discutido Node. js de la teoría a la práctica, comenzando con sus metas y ambiciones, y terminando con sus puntos dulces y trampas. Cuando la gente se enfrenta a problemas con Node, casi siempre se reduce al hecho de que las operaciones de bloqueo son la raíz de todos los malos 99 de los malversamientos de los nodos vienen como una consecuencia directa. En el nodo, las operaciones de bloqueo son la raíz de todo el mal 99 de los malos usos del nodo vienen como una consecuencia directa. Recuerde: Node. js nunca se creó para resolver el problema de escala de cálculo. Se creó para resolver el problema de escalado de E / S, lo que realmente hace bien. Por qué utilizar Node. js Si su caso de uso no contiene operaciones de uso intensivo de la CPU ni tiene acceso a ningún recurso de bloqueo, puede aprovechar las ventajas de Node. js y disfrutar de aplicaciones de red rápidas y escalables. Bienvenido a la web en tiempo real. Acerca del autor Ver perfil completo raquo miembro desde February 12, 2013 Tomislav es un ingeniero de software, consultor técnico y arquitecto con más de 10 años de experiencia. Se especializa en aplicaciones de JavaScript y Node. js en tiempo real, con escalabilidad máxima y escalabilidad, con experiencia previa en C, Java y Ruby. Él es un ágil Kanban practicante que le encanta colaborar en proyectos de desarrollo. Haz click para continuar. Comentarios Para DBs relacionales en Nodo, me gusta bookshelfjs. org/ Artículo impresionante Estoy de acuerdo en que node. js tiene algunos casos de uso muy adecuado. Sin embargo, quiero comentar sobre algo que es un poco de una molesta cosa mía - ojalá no lo contraste con un inexistente paja-hombre quottraditionalquot sistema en quothow it worksquot. 1) Ningún servidor genera un hilo por solicitud (utilizan grupos de hilos o grupos de procesos). 2) Usted dice que el costo de cambio de contexto como si sólo se aplica a los temas del sistema operativo. Los marcos de espacio de usuario deben guardarse y cargarse de la misma manera. Además, el sistema operativo lo hace con unas pocas instrucciones, aprovechando el soporte especializado del hardware, lo que el espacio del usuario no puede hacer. 3) De forma similar, los subprocesos de espacio de usuario (es decir, los marcos o los cierres si no desea hablar de subprocesos) toman recursos de memoria de la misma manera que los hilos del núcleo. No es como si cada hilo del sistema tenga su límite de pila completo asignado, por lo que es un análisis injusto. Los sistemas normales regularmente tienen más de 4000 sin llegar a ninguna parte cerca de donde usted lo ha fijado. 4) El gran problema con la concurrencia de un solo hilo es la falta de paralelismo. Claro, puede manejar miles de peticiones por segundo, pero sólo una CPU en su servidor de 40 núcleos va a hacer cualquier trabajo. De todos modos, todo lo anterior es en relación con un párrafo bastante menor en su excelente post. El nodo no es realmente culpable de esto, sólo que hay un montón de FUD por ahí alrededor de hilos y procesos que la gente suele usar para justificar diseños insanos (y evitar hilos cuando son completamente el enfoque correcto para la mayoría de las situaciones). Todos sus consejos sobre computación aplicaciones pesadas no podría ser más equivocado. Ciertamente es cierto que el intento de computación pesada en línea con el ciclo de solicitud-respuesta, es una mala idea, pero lo mismo podría decirse de los entornos roscados. Si tiene operaciones vinculadas a la CPU, es una buena idea manejarlas con procesos de trabajo. JavaScript y Node en particular son realmente muy adecuados para manejar la computación distribuida - especialmente con el buen soporte para la programación de estilo funcional. Si escribe sus algoritmos usando funciones puras y distribuye la carga de trabajo a los trabajadores, puede distribuir fácilmente su carga de trabajo sobre los clústeres en red. El gran soporte de Node para la creación de redes lo convierte en un entorno ideal tanto para tareas de computación como de orquestación, y órdenes de magnitud más rápidas que Ruby en ambos. Muy útil. Muchas gracias No querrás bloquear ningún proceso de Node. js que esté manejando solicitudes de servidor, pero eso no significa que no deberías hacer cálculos pesados ​​detrás de un servidor Node. js. Siempre y cuando el proceso que realiza los cálculos pesados ​​se genera de forma asincrónica desde el proceso del servidor. Aún así, podrías terminar bloqueando tu proceso de Node. js si lo has dejado, pero eso también es cierto con el servidor de subprocesos tradicional. Esto va a hacerme salir para ser un noob gigante pero puede usted darme un ejemplo de una operación del quotblocking Cualquier tal sistema híbrido I39m que piensa: Utilice Node. js para procesar una petición simplemente colocándola en una cola del proceso, vuelta Un mensaje al cliente indicando algo como quotcalculating. Quot. Entonces Node. js es libre de continuar con la siguiente solicitud. La cola de procesos se puede ejecutar a través de un hilo de diferencia (o incluso múltiples hilos). A medida que se completan, envían sus resultados a la cola de Node. js39s que luego la retransmitirá al cliente original. Por supuesto, esto significa que algunas claves de ID deben acompañar cada elemento de esta cola para asegurar que los datos correctos se devuelven a la correcta cliente. Cualquier cosa como esto posible O incluso ya implementado Gran artículo, gracias :) Tomislav, gracias por este artículo muy bien escrito y conciso. Hemos estado usando MongoDB y Node. js (en combinación con AngularJS para la parte que enfrenta a los usuarios) durante 2 años y no podíamos imaginar jamás volver a Flash (después de 10 años de experiencia) o JEE / RDMS. Así que se reduce a sólo un lenguaje de programación (JS), un formato de datos (JSON) y un paradigma de programación (Async), wow. That39s con mucho la mejor explicación hacia fuera allí sobre Node. js. Finalmente entendí que es muy útil (en ciertos escenarios) y no sólo un bombo. Gracias mucho esto fue muy informativo Nodo funciona bien con bases de datos relacionales, sólo don39t utilizar un ORM. SQL no es tan difícil de aprender. ) Es cierto que, pero pensé que como una industria se sobrepuso a la idea de escribir todos los SQL manualmente. Las herramientas son buenas para las operaciones comunes, las herramientas que sólo salen de la manera cuando es necesario escribir algunos detalles manualmente, de lo contrario reducir la posibilidad de errores y problemas de seguridad (que sucede con los desarrolladores más jóvenes si lo queremos o no). Hola Adin, permítanme comentar de nuevo 1) mismo escenario sucede, hay una cantidad limitada de hilos que sirven cantidad limitada de clientes. 2/3) La presentación referenciada muestra algunas mediciones y números, usted puede estar muy bien en los internos, pero la descripción general común sigue siendo una comparación general de cómo funcionan las cosas entre esos dos mundos. 4) las opciones de paralelización también se discuten en el artículo - como procesos de trabajo en segundo plano, o varios procesos de nodo detrás de un proxy inverso, o con Node clustering API (que todavía está en Experimental, pero estará allí eventualmente). Gracias por los comentarios excelentes y la calidad de comentarios sobre el artículo con esa información adicional, lo aprecio. Sí, puede tener varios procesos de trabajo, incluso comunicarse a través de Message Queue (MQ). Esos trabajadores pueden ser procesos Node separados (ya que el nodo es de subproceso único, a menos que experimente con la API de clúster - no lo he probado todavía porque la API es muy temprana y probablemente immmature), pero puede ser cualquier otro idioma. He trabajado en un sistema de este tipo que ejecuta C on Mono para el procesamiento de fondo en una arquitectura distribuida CQRS. Cualquier cálculo que mantenga la CPU ocupada hasta que finalice el cálculo. Imagine alguna operación que requiera 2 segundos para realizar el cálculo. Hit que con 100 clientes - obtendrá un retraso de 200 segundos. Tenga en cuenta el artículo al que he hecho referencia, que explica el bloqueo del bucle de eventos: zef. me/4561/node-js-and-the-case-of-the-blocked-event-loop Sí, eso cae bajo la idea de tener 39reprocesos de trabajo de backend39 en un sistema distribuido. A medida que el sistema se distribuye, los trabajadores pueden utilizar cualquier idioma / plataforma, incluyendo Node. Gracias por sus comentarios. Estoy de acuerdo en que, por completo, para los procesos de trabajo que podría utilizar JS cuando se ajusta, y que implica Node. js como lo que funciona JS en el servidor, pero también puede utilizar otros idiomas que hacen el trabajo en particular rápido. Para ORMs en general, sólo los veo como una herramienta que puede conseguir algo hecho rápido para un novato, pero terminan realmente engrasando los trabajos más adelante. Lo más parecido que uso para un ORM es un envoltorio PDO (que tomé prestado y reescrito de un antiguo compañero de trabajo), que ayuda con la escritura de las declaraciones de DOP. Github / ellisgl / GeekLab-XPDO Disculpas por la pared del texto. Excelente discusión 1) De acuerdo. Pero los hilos y los procesos son herramientas poderosas. Por eso un híbrido de hilos / procesos y sistemas de eventos suele ser el mejor en el mundo real. Como el muy querido nginx :) 2/3) Lo siento, no puede haber sido claro. Cuando dije FUD con respecto a hilos y procesos, me refería a la presentación referenciada. Es sólo un puñado de microbenchmarks específicamente diseñados para demostrar un cierto punto. (Which is fair, given that it39s a lightning fair and can be a bit polemic. In fact, it39s a great talk. But these synthetic micro-benchmarks are not the basis for a fair and through comparison.) To say the difference between nginx and apache benchmarks is purely because of context switching is an extreme oversimplification. Nginx is specifically designed to serve HTTP requests really, really quickly in common circumstances (IMO generally by a tight coupling with the latest OS event systems, etc.). You could specifically measure the overhead of context switching, and I would wager it39s trivial. 4) But then aren39t you at the mercy of the horrible quotprocess overheadquot the referenced presentation talks about -- can39t have it both ways :) (To be clear, my position using threads/processes or whatever is not in and of itself a problem. There are way more important design factors there, the OS overhead of those entities is pretty trivial. Hence I hate it when people adopt a silly design based on the idea thread-are-bad or processes-are-bad or some other such nonesense). Everything always needs to be put in the right context. I have presented possible situations, to analyze each one deeply I39d need a book :-) Still, I really appreciate your comments and insights, they are valuable addition to the article. Thank you for those. When use node. js as api server, and the back-end db is the bottleneck, if the clients are the other applications, not user interface, can we just let these client requests hang there waiting for db operation complete(sine node. js can handle massive concurrent connections easily) Is a MQ necessary in this scenario In my opinion, node. js is right the queue. ORM does not exist to make query languages quoteasierquot, it39s a tool used to encapsulate database concerns, isolating them from the application. There are several benefits, but ultimately, it makes applications easier to test and maintain years down the road. Excuse the tangent, nothing to do with node. Yes, you could, but Ruby would be a poor choice if your aim is performance. ) thank you for a great article. By using the node. js child process nodejs. org/api/childprocess. html - would you be able to overcome the high computational blocking Fibonacci issue any real life examples What of the Facebook example you used. When a user clicks on the like button there is an immediate acknowledgement but the data is written later. Cant that be an example of node used with relational db Anyway what makes up the message queue Maybe go-lang is alternative choice. ) This article is great, except for the part where it says don39t use NodeJS for computation because it doesn39t have threads. Since when do we need threads Run child processes. The only advantage to running threads over child processes is shared memory. Last time I checked, any system large enough for this entire debate to be relevant anyway is going to span multiple servers anyway, their by nullifying any benefit of threads. So, get it out of your head that NodeJS can39t do CPU intensive work. And, if you can39t, contact HildoerSystems, and we can fix all the stuff you built wrong with NodeJS. One application that few people use, but could be really fanastic, is using NodeJS to build a desktop application. There39s plenty of packages out there - personally, I favour Node-Webkit github/rogerwang/node-webkit. Hi, nice article. However I would like to point one thing, NodeJS is not running in a single thread. The programmer doesn39t have to spawn new threads, they are handled by node itself on event basis. NodeJS is evented, each function call per event will run in a separate thread. That approach encourages writing lighter functions. If your function does a lot of computation, reactor it into smaller ones and they all will run in separate threads. Think about the example where you process file while streaming. That is possible thanks to threads. Great article BTW, what software did you use to make the images/wireframes This is very well written. Thank you for this gt The technique used to avoid exceptions bubbling up to the surface is passing errors back to the caller as callback parameters Excuse me, but that seems misled. In my understanding, Node-style callbacks(nodeguide/style. htmlcallbacks) (i. e. the pattern of passing errors as the first param to callbacks) are a side-effect of the event queue (returning control as soon as possible to allow for concurrency) itself rather than a design to avoid interrupting flow. The fact that exceptions do not bubble are actually quite often a source of errors, especially to newcomers. Great Article. Wondering who made the beautiful diagrams :) Great article, thanks :) BTW, which tool do you use to draw the images For those that are curious, it seems the images were created with Adobe Photoshop CC. I checked this by looking at the EXIF data of one of the images: exifdata/ File Size 61 kB File Type PNG MIME Type image/png Image Width 624 Image Height 600 X Resolution 72 Y Resolution 72 Color Space sRGB Color Mode 3 Compression Deflate/Inflate Orientation Horizontal (normal) XMP Toolkit Adobe XMP Core 5.5-c014 79.151481, 2013/03/13-12:09:15 Creator Tool Adobe Photoshop CC (Macintosh) Also, the fact that javascript is not able to check type compliance introduces dificulty in expontaneous organization of huge number of coders updating the same codebase simultaneously. mmmm. disagree, if you use correctly a good ORM (take a look at Mature ORMs) you get also a distributed cache of your Relational Database that allows you more performance for the same bucks and more scalability of your sistem. ORM is not just for easing the life to newies. It is non sense to use a non-blockin sistem such as node. js, if at the end you get blocked at your Database. But using a ORM that way, is not for newbies. Glad you mention, most people don39t mention this. I39d rather keep Node decoupled from the browser and keep the flexibility of running the frontend on platforms that normally don39t run Node like smartphones. For that matter, since you can do an async shell to a console application, you could easily write your worker in, for instance golang, and then use a generic pool to limit your cpu workers. from there, you can shell out to a more efficient worker. You can also do that for CPU intensive JS as well, I did this for my scrypt-js module (there are binary modules that are more performant, but I wanted one without compiled dependencies). It39s not that hard to queue work to other systems, and no reason node can39t be used to orchestrate said work. Could could use an intermediate system such as TypeScript, you can also use a linter (jshint) and even require a level of test coverage in order for release. Getting 100 test coverage is generally very easy in scripted environments. Would suggest looking into Mocha, Chai, and Proxyquire. If you aren39t writing unit tests, type safety really doesn39t give you much. I am beginning to find Node. js quite interesting. However, the paradigm it appears to be promoting is hardly new to IT. In the mainframe communications world we called such capabilities, quotre-entrantquot, where a single process could handle a high level of calls to it. Microsoft implemented similar capabilities with its Singleton object infrastructure and I imagine the Java world has done similar implementations. Oddly enough, the Microsoft recommendation for enhancing scalability across the wires to back-end services was to promote the quotSingle Callquot object structure or one object instance per calling request. Thus, the argument made for Node. js is actually contrary to the Microsoft recommendation BTW, a recommendation I never quite understood. In any event, as a business ASP. NET developer, I am not sure if I would find any use for a Node. js implementation, though our web designer may. On another note, I would like to add my own opinion on the use of ORMs. ORMs are great tools when faced with an existing database structure against the requirements of a new application as the ORM can handle a lot of the mundane, repetitive coding that is usually found with any database application. However, because ORMs are high-level layers, they are usually not the most efficient options to use against databases whereas direct access through native providers are. In many respects, better to do the repetitive coding for efficiency over applying a heavy-weight interim layer such as an ORM. Very interesting observation. I39d like someone to elaborate a bit more on that. I would like a more concrete example, like some piece of concrete code calling an async heavy-computational function, and someone explaining what happens if that is run in a multicore equipment. Does the thread that was sercing http requests gets blocked Or another thread is used for that Node is terrible as a web server. Even the creator suggests that this is not what Node is intended for, and that it should be leveraged for it39s strengths. JavaScript quotEverythingquot, just like worker processes, is ludicrous. This is ridiculous. Node was built with the web as first class, and it excels as a web server. It is rapidly replacing Ruby and PHP in many enterprise organizations because it has demonstrably boosted both application performance (reduced page-load times, etc. ) and developer productivity. You can in fact create multi-threaded servers using Node. js to offer more stable performance but it does take a lot of extra work (see the built-in cluster module and the childprocess module). I have created a framework which runs on multiple CPU cores and solves much of the issues discussed in this post. Check it out: nombo. io/ Connor James Leech does something like mongoose. js solve the node relational database issue mongoosejs/ Yes - see the queue/pre-forked worker pool approach adopted by EWD. js: gradvs1.mgateway/download/EWDjs. pdf Summarised here: gradvs1.mgateway/download/EWDjsMechanics. pdf yeah, I was wondering about it too. great visual awesome post. Erick Ruiz de Chavez Just to complement what Tracker1:disqus said on his comment, JavaScript is usually criticized about the type checking (and many other misunderstood features, like quotthisquot), but the truth is that JavaScript is just very different to what most of the developers are used to do, and most of the developers who sadly have bad comments about it are just those who haven39t had the interest or the time to understand how it really works. JavaScript development is not only about the language itself but also about the tools you use to work with it, to mention some more you should really take a look at Grunt, Uglify, Yeoman, CoffeScript, etc. Erick Ruiz de Chavez I might as well make myself a giant noob, but to put a quick example, any disk I/O operation is considered a blocking operation as it has to perform a physical operation to read some data from the disk. Another blocking operation example is querying a DB, where you basically have to wait for the response before doing anything else. I39d say, any sort of computational operation will be as blocking as the time it takes to complete. In any of the above examples, you usually have your blocking request on line A and line B wont be executed until line A is completed. Node. js instead is asynchronous, so line A is requested and then queued, and line B is executed no matter if line A is completed or not when line A is complete, you are notified either with a callback or with an event and then you can continue doing whatever you need to do with such result. Very helpful article npm install felixge/node-mysql. That might be the most useful repository I39ve seen in ages. Erick Ruiz de Chavez I have a small example of mysql and node. js at github/erickrdch/node-mysql-demo How about: quotWhy the hell would I read an article without an obvious date and time stampquot Nice article, indeed. But, hfuti:disqus, you39re wrong in saying quotNodeJS is not running in a single thread. each function call per event will run in a separate thread. quot As far as I understood, the main NodeJS event loop consuming your JS code in fact runs in a single thread. All potentially blocking and/or long-running tasks like disk I/O is delegated to and executed by libuv as part of the node runtime engine which spawns a limited number of threads made available as thread pool. Said this, it39s obvious that the main event loop thread is not affected or blocked by other (yet again asynchronous) code execution. So, for example, file I/O with the fs module itself is implemented in a non-blocking manner - in the end as good as the OS/kernel allows non-blocking operations. Of course foreign processes or threads could always be spawned by custom modules or 3rd party services (worker processes). And yes, there are runtime env projects handling more than one node process and their threads on the same machine or cpu cluster. But that39s another story. Feel free to correct me if I39m wrong This is fantastic. Very well written article. You put a lot of thought into it. Quick node/express question I am I am adding rapid data entry, not batch, data entry to my system I have a form (mfntapes) that works great. I have a test form (joe) the prompts for the number of times I want to call the mfntapes form The gist contains the code, fails to work, the after prompting for cnt attempts to call for mfntapes cnt times. The question is how to call form mfntapes x number of times where x is a vairable See lines 45-55 of gist. github/toulon/9571625 ORM for real projects are useless hone. Nice article :-) gt SERVER-SIDE WEB APPLICATION W/ A RELATIONAL DB BEHIND I wonder why Node is not good for that You have promise based SQL libraries (like Knex) which enables non-blocking queries. Node has no opposition with relational databases: it has no interest with blocking I/O drivers only. Relational or not relational. I wish NodeJS was not (almost) systematicallty presented as THE de facto alternative to the traditional threaded webserver. Async IO is not exclusive to NodeJS Most major languages out there - including Java and PHP - have async IO frameworks similar to NodeJS. This wiki page lists most of them: en. wikipedia. org/wiki/Reactorpattern I39m not saying NodeJS doesn39t have its merit, but I39m sick and tired of seeing people flocking to it as if it39s the only async IO stack available, and the only alternative to the good ol39 PHP or Rails stack. To be honest, we may be stuck with Javascript on the browser, and will be for a very long time (except if Javascript becomes just another target platform/language thanks to asm. js), but I can39t come up with any good reason to use it on the server side in favor to other available languages. Most of the alternatives are just way better as a language, have better standard libraries, tools and resources. Please stop spreading Javascript on the server, it39s creepy :p Jarle Leopold Moe How would you upload files What about Directory integration (Active Directory, Open Directory) What about communication with external services All request depending on a response from any of these types of services would block the calls. Node. js is single-threaded it39s only applicable for certain types of tasks. These re great examples of why Node is so much better than the competition at web services. None of thee are blocking operations in Node. They39re asynchronous. While other servers waste resources spinning off separate threads, Node fires off an event-driven asynchronous operation and keeps taking more requests in the meantime. The practical upshot is that porting web services from PHP or Ruby can deliver between 2x and 10x improvements in simultaneous connections and typically 30 - 60 improvements in average response times. Lots of big companies are doing web Node projects just for these reasons, including Adobe, Paypal, eBay, Walmart, Yahoo. Groupon, Under, etc. very nice article and very clear thought regarding node. js where to use and where not Every major application development platform has already had support for HTML5 for the past several years, including websockets for bi-directional communication. Add to this the strong types, multi-threading and the tons of other stuff that languages such as Java have to offer and I seriously question why anyone would waste their time using this. Just want to mention that node is not the only server side option for javascript especially since oracle put the nashorn javascript engine on the jdk. Now you can also use all the jvm goodness from javascript we are using vert. x as the async server and nashorn to use javascript. You can see some code samples in this module github/core9/module-nashorn the project site is core9.io. This is an amazing overview. Thank you Very well written. Gracias por compartir. I39m with you. For trivial application an ORM is fine. You have to remember that most devs really only have experience with trivial applications. So they will argue for an ORM because they can39t learn SQL or don39t have the time or staff to right stored procs. And they have never heard of Memcached and so think the ORM is a cache. what ever. And the weirdest excuse I hear is about decoupling. The ORMs I have had the misfortune of running across do the opposite. They very much tightly couple the UI to the database. ORM layers are large and buggy. So how do you test it Yeah, good luck unit testing it (which you have to do because they are buggy). If you are integrating with AD then you are probably in a Microsoft shop. And if you are uploading files to a web server then your environment isn39t very sophisticated. So for you, you probably should just stick with IIS and VB. Net. Microsoft public recommendations for architecture are a joke. Microsoft is a marketing and licensing company. They are not a tech company primarily If you have a quothuge number of coders updating the same codebase simultaneouslyquot you have larger problems. Dev teams don39t scale well. I would run. With too many cooks in the kitchen the broth will spoil. There is going to be no accountability and no responsibility with that many people contributing. Why Node is different - using bar as analogy bahmutov. calepin. co/why-node-is-different. html lta hrefquotamjad-almadinah. org/D8AED8AFD985D8A7D8AA-D8A7D984D8AAD986D8B8D98AD981/D8B4D8B1D983D8A9-D8AAD986D8B8D98AD981-D8B4D982D982-D8A8D8A7D984D985D8AFD98AD986D8A9-D8A7D984D985D986D988D8B1D8A9/quotgt lt/agt lta hrefquotamjad-almadinah. org/D8AED8AFD985D8A7D8AA-D8A7D984D8AAD986D8B8D98AD981/D8B4D8B1D983D8A9-D8AAD986D8B8D98AD981-D981D984D984-D8A8D8A7D984D985D8AFD98AD986D8A9-D8A7D984D985D986D988D8B1D8A9/quotgt lt/agt lta hrefquotamjad-almadinah. org/D8AED8AFD985D8A7D8AA-D985D983D8A7D981D8ADD8A9-D8A7D984D8ADD8B4D8B1D8A7D8AA-D988D8B1D8B4-D8A7D984D985D8A8D98AD8AFD8A7D8AA/D985D983D8A7D981D8ADD8A9-D8ADD8B4D8B1D8A7D8AA-D8A8D8A7D984D985D8AFD98AD986D8A9-D8A7D984D985D986D988D8B1D8A9/quotgt lt/agt lta hrefquotnsmat-dammam. org/D8AED8AFD985D8A7D8AA-D8A7D984D8AAD986D8B8D98AD981/D8B4D8B1D983D8A9-D8AAD986D8B8D98AD981-D8B4D982D982-D8A8D8A7D984D8AFD985D8A7D985/quotgt lt/agt lta hrefquotnsmat-dammam. org/D8AED8AFD985D8A7D8AA-D8A7D984D8AAD8B3D984D98AD983-D988D8A7D984D8AAD8B3D8B1D8A8D8A7D8AA/D8B4D8B1D983D8A9-D8AAD8B3D984D98AD983-D985D8ACD8A7D8B1D98A-D8A8D8A7D984D8AFD985D8A7D985/quotgt lt/agt lta hrefquotnsmat-dammam. org/D8AED8AFD985D8A7D8AA-D8A7D984D8AAD986D8B8D98AD981/D8B4D8B1D983D8A9-D8AAD986D8B8D98AD981-D985D986D8A7D8B2D984-D8A8D8A7D984D8AFD985D8A7D985/quotgt lt/agt lta hrefquothamd-almadinah. org/D986D982D984-D988D8AAD8AED8B2D98AD986-D8A7D984D8A7D8ABD8A7D8AB/D986D982D984-D8B9D981D8B4-D8A8D8A7D984D985D8AFD98AD986D8A9-D8A7D984D985D986D988D8B1D8A9/quotgt lt/agt lta hrefquothamd-almadinah. org/D8AED8AFD985D8A7D8AA-D8A7D984D8AAD986D8B8D98AD981/D8B4D8B1D983D8A9-D8AAD986D8B8D98AD981-D8B4D982D982-D8A8D8A7D984D985D8AFD98AD986D8A9-D8A7D984D985D986D988D8B1D8A9/quotgt lt/agt lta hrefquothamd-almadinah. org/D8AED8AFD985D8A7D8AA-D8A7D984D8AAD8B3D984D98AD983-D988D8A7D984D8AAD8B3D8B1D8A8D8A7D8AA/D8B4D8B1D983D8A9-D983D8B4D981-D8AAD8B3D8B1D8A8D8A7D8AA-D8A7D984D985D98AD8A7D987-D8A8D8A7D984D985D8AFD98AD986D8A9-D8A7D984D985D986D988/quotgt lt/agt lta hrefquothamd-dammam. org/D986D982D984-D988D8AAD8AED8B2D98AD986-D8A7D984D8A7D8ABD8A7D8AB/D8B4D8B1D983D8A9-D986D982D984-D8A7D8ABD8A7D8AB-D8A8D8A7D984D8AFD985D8A7D985/quotgt lt/agt lta hrefquothamd-dammam. org/D985D983D8A7D981D8ADD8A9-D8A7D984D8ADD8B4D8B1D8A7D8AA-D988D8B1D8B4-D8A7D984D985D8A8D98AD8AFD8A7D8AA/quotgt lt/agt lta hrefquothamd-dammam. org/D8AED8AFD985D8A7D8AA-D8A7D984D8AAD986D8B8D98AD981/D8B4D8B1D983D8A9-D8AAD986D8B8D98AD981-D985D986D8A7D8B2D984-D8A8D8A7D984D8AFD985D8A7D985/quotgt lt/agt lta hrefquotkema-dammam. org/D985D983D8A7D981D8ADD8A9-D8A7D984D8ADD8B4D8B1D8A7D8AA-D988D8B1D8B4-D8A7D984D985D8A8D98AD8AFD8A7D8AA/D8B4D8B1D983D8A9-D985D983D8A7D981D8ADD8A9-D8ADD8B4D8B1D8A7D8AA-D8A8D8A7D984D8AFD985D8A7D985/quotgt lt/agt lta hrefquotkema-dammam. org/D8AED8AFD985D8A7D8AA-D8A7D984D8AAD8B3D984D98AD983-D988D8A7D984D8AAD8B3D8B1D8A8D8A7D8AA/D8B4D8B1D983D8A9-D983D8B4D981-D8AAD8B3D8B1D8A8D8A7D8AA-D8A7D984D985D98AD8A7D987-D8A8D8A7D984D8AFD985D8A7D985/quotgt lt/agt lta hrefquotkema-dammam. org/D8AED8AFD985D8A7D8AA-D8A7D984D8AAD8B3D984D98AD983-D988D8A7D984D8AAD8B3D8B1D8A8D8A7D8AA/quotgt lt/agt lta hrefquotnsmat-dammam. org/D985D983D8A7D981D8ADD8A9-D8A7D984D8ADD8B4D8B1D8A7D8AA-D988D8B1D8B4-D8A7D984D985D8A8D98AD8AFD8A7D8AA/D8B4D8B1D983D8A9-D8B1D8B4-D985D8A8D98AD8AFD8A7D8AA-D8A8D8A7D984D8AFD985D8A7D985/quotgt lt/agt lta hrefquothamd-dammam. org/D8AED8AFD985D8A7D8AA-D8A7D984D8AAD986D8B8D98AD981/D8B4D8B1D983D8A9-D8AAD986D8B8D98AD981-D985D986D8A7D8B2D984-D8A8D8A7D984D8AFD985D8A7D985/quotgt lt/agt lta hrefquotkema-dammam. org/D8AED8AFD985D8A7D8AA-D8A7D984D8AAD8B3D984D98AD983-D988D8A7D984D8AAD8B3D8B1D8A8D8A7D8AA/quotgt lt/agt lta hrefquotforsan-almadinah/D8AED8AFD985D8A7D8AA-D8B9D8B2D984-D988D8AAD986D8B8D98AD981-D8A7D984D8AED8B2D8A7D986D8A7D8AA/D8BAD8B3D98AD984-D8AED8B2D8A7D986D8A7D8AA-D8A8D8A7D984D985D8AFD98AD986D8A9-D8A7D984D985D986D988D8B1D8A9/quotgt lt/agt lta hrefquotforsan-almadinah/D8AED8AFD985D8A7D8AA-D8A7D984D8AAD8B3D984D98AD983-D988D983D8B4D981-D8A7D984D8AAD8B3D8B1D8A8D8A7D8AA/D8B4D8B1D983D8A9-D983D8B4D981-D8AAD8B3D8B1D8A8D8A7D8AA-D8A7D984D985D98AD8A7D987-D8A8D8A7D984D985D8AFD98AD986D8A9-D8A7D984D985D986D988/quotgt lt/agt lta hrefquotforsan-almadinah/D8AED8AFD985D8A7D8AA-D985D983D8A7D981D8ADD8A9-D8A7D984D8ADD8B4D8B1D8A7D8AA-D988D8B1D8B4-D8A7D984D985D8A8D98AD8AFD8A7D8AA/D985D983D8A7D981D8ADD8A9-D8ADD8B4D8B1D8A7D8AA-D8A8D8A7D984D985D8AFD98AD986D8A9-D8A7D984D985D986D988D8B1D8A9/quotgt lt/agt lta hrefquotamjad-jeddah. org/D8AED8AFD985D8A7D8AA-D8A7D984D8AAD986D8B8D98AD981/D8B4D8B1D983D8A9-D8AAD986D8B8D98AD981-D985D8B3D8A7D8A8D8AD-D8A8D8ACD8AFD8A9/quotgt lt/agt lta hrefquotamjad-jeddah. org/D8AED8AFD985D8A7D8AA-D8A7D984D8AAD986D8B8D98AD981/D8B4D8B1D983D8A9-D8AAD986D8B8D98AD981-D981D984D984-D8A8D8ACD8AFD8A9/quotgt lt/agt lta hrefquotnsmat-jeddah. org/D8AED8AFD985D8A7D8AA-D8A7D984D8AAD8B3D984D98AD983-D988D8A7D984D8AAD8B3D8B1D8A8D8A7D8AA/D983D8B4D981-D8AAD8B3D8B1D8A8D8A7D8AA-D8A7D984D985D98AD8A7D8A9-D8A8D8ACD8AFD8A9/quotgt lt/agt lta hrefquotnsmat-jeddah. org/D8AED8AFD985D8A7D8AA-D8A7D984D8AAD986D8B8D98AD981/D8B4D8B1D983D8A9-D8AAD986D8B8D98AD981-D8A8D8ACD8AFD8A9/quotgt lt/agt lta hrefquotnile7/D8B4D8B1D983D8A9-D985D983D8A7D981D8ADD8A9-D8ADD8B4D8B1D8A7D8AA-D988D8B1D8B4-D985D8A8D98AD8AFD8A7D8AA-D8A8D8A7D984D982D8B7D98AD981quotgt lt/agt lta hrefquotnile7/D8B4D8B1D983D8A9-D8AAD8AED8B2D98AD986-D8A3D8ABD8A7D8AB-D8A8D8A7D984D8ACD8A8D98AD984quotgt lt/agt lta hrefquotnile7/D8B4D8B1D983D8A9-D8B9D8B2D984-D8A3D8B3D8B7D8AD-D8A8D8A7D984D8AFD985D8A7D985quotgt lt/agt lta hrefquotstorify/monyhusseinquotgtlt/agt lta hrefquotmonyhussein. deviantart/quotgtherelt/agt lta hrefquotfreee4des. blogspot/quotgtherelt/agt lta hrefquotemyhusssein. tumblr/quotgtlt/agt lta hrefquotkenanaonline/users/monyhussein/quotgtlt/agt Just to let you know you have quotsupport supportquot in How it works under-the-hood is pretty interesting. Compared to traditional web-serving techniques where each connection (request) spawns a new thread, taking up system RAM and eventually maxing-out at the amount of RAM available, Node. js operates on a single-thread, using non-blocking I/O calls, allowing it to support support tens of thousands of concurrent connections (held in the event loop). Isn39t it possible to get the date of posting of your article or all your posts for that matter. It is really disturbing to read technical posts without dates. thanks You mention Node. js is good for a chat application because it39s not CPU intensive. I can39t think of too many use cases that don39t require much CPU. For example, could Twitter be built with Node It seems there39s a lot of computation required just to generate your feed. Node. js uses certainly can39t be so narrow. Great article. Gracias. There39s an old joke: you39re not a paranoid if they39re really out to get you. That39s the attitude that should be taken when it comes to Web application security. One thing that bothers me about Node. js is that I have no insight into how secure it is. When an environment like Grails, where I have Java/Groovy running on Tomcat I have some confidence in Tomcat security, if for no other reason than the fact that Tomcat has been around a long time and has evolved. This isn39t true with Node. js. I was also looking at the Node. js libraries. At least for the file access, it appears to be nothing more than a thin layer over the POSIX file system calls. I like the Java or even the C file abstractions more. The main argument that I see for Node. js (made in this post) is that it has really lightweight threads and that you can have JavaScrip everywhere. This last issue is an attraction for those who only know JavaScript. As far as the light weight threads, this is not so much a language issue as a platform support issue. It should be possible to support this kind of thread model in another language. Toptal designer did the design for them. your comment is ridiculous too, ORM is not a everyone39s accepted pattern. The irony is that lambda39s (aka, anonymous methods) are the basis of both javascript and the preferred technique for C39s multiple implementation of the same callback pattern, albeit with full type safety. In fact node39s major characteristics (2-way, lightweight, asynchronous has effectively been implemented in C as quotSignalRquot, and there are several language features which are both asynchronous and natively multithreaded, (unlike node. js). Now I could understand if your experience with ORM39s was limited to Hibernate (absolutely awful, one of the worst implementations of a major concept I39ve ever had the displeasure to work with) or even EF, which at least is fairly powerful and expressive due to LINQ, if data nanny overkill. But a micro-ORM like Dapper gives you all the flexibility and power of direct SQL with the benefits of rich data manipulation via objects, and is fast, very fast. And I39m sorry, but OOP is a well proven, very effective design strategy if you know what you are doing, i. e. you are a pro. I see three major problems with the node. js approach that no one seems to have a good answer for: So you start with the premise that there are such inefficiencies in waiting for IO that there is a huge potential there. So yeah, you39ve got great concurrency, right until you get to the first blocking library, a database, a file server, etc, which is practically every major piece of functionality written. So it39s just hurry up and wait for 10,000 connections instead of 100, ok that39s something, but where does it get you So then you start rewriting all those services asynchronously, but that39s just a snake eating its own tail, because that39s hurry up and wait too: Because in the end every database on earth ultimately comes to a magnetic arm skipping across a disk or reading solid state memory, and that39s assuming you39re on the same machine, as opposed to distributing data across a pool of far slower network connections. Then you have the single threaded issue: There is probably no more misused language than Javascript because the barriers of entry are so low. And while early adopters might understand a bad practice when they see one, most javascript programmers simply have no idea what they are doing. Thirdly, Javascript is not exactly a particularly fast language, so the advice seems to be don39t do compute intensive tasks. Where does that get you So you end up with an elegant solution to one category of issues, but you39re trapped there, with no way out of the non-compute intensive, hurry up and wait ghetto. Wow, that is one seriously ignorant statement. Uploading files to webservers is THE stated rational of node. js39s inventor for why he wanted a non-blocking library. So when you fanboi39s break out of the single threaded, slow dynamic world of cut and paste code with zero type safety, multithreading, and only one trick pony (lambdas) to match. Net39s multiple asynchronous capablities, (all so that you can get 10x more users to hurry up and wait for IO), then you can lecture us about quotsophisticationquot. The. Net framework has a vastly more advanced feature set than any language you can name, period, and IIS, properly configured, can beat the piss out of Apache and can readily match nginx as a reverse proxy or for static content. In the end you39ve got several problems which are intractable: 1. Javascript is slow, and your technology of choice is single-threaded, so intensive compute tasks are off the table. 2. Javascript debugging and testing blows in comparison with any typed language. Pro39s use extensive testing, not fly by the pants 39hey it works39. 3. The 39everything is modular39 approach is not an architecture, it39s an invitation to chaos, like Perl or PHP. 4. Concurrency doesn39t buy you crap if all you are doing is waiting for some other IO bound process, which is pretty much everything worth doing with computers. 5. The quality and experience of many javascript programmers (not node. js programmers necessarily, but it39s popularity will bring them) is remarkably poor, as demonstrated by comments in which fanboi39s prove that they have no idea how other systems that actually don39t ignore any computing problem they can39t solve work. ORM is just a work around for the problem of impedance mismatch, nothing else. Its not big deal, about OO its a cross paradigm like AOP and its not really based in nothing else beyond encapsulation. Without procedural paradigm OO does nothing, every real skilled programmer already knows that. Impedance mismatch involves all sorts of ramifications, especially in regards to maintainability, portability, extensibility and performance. To quote Ethan above (since my explanation obviously didn39t take): quot. it39s a tool used to encapsulate database concerns, isolating them from the application. There are several benefits, but ultimately, it makes applications easier to test and maintain years down the road. quot quotabout OO its a cross paradigm like AOP and its not really based in nothing else beyond encapsulation. Without procedural paradigm OO does nothingquot Ok, I39ll be sure to spread the word that we should stop fooling around with all this esoteric OOP stuff and get back to a language that lets us do everything vis-a-vis encapsulation: VB6. You39d think a Javascript programmer might want to mention inheritance, if not polymorphism, since javascript has a relatively unusual mechanism for it: prototypes. A singleton is an instantiable (non-static) object with a private constructor so that only a single instance can be created. (Imagine an instance class with a static property exposing an instance of itself that depends upon a private instance constructor). It was actually implemented in Java before. Net existed. Perhaps what you are thinking of is a non-blocking Callback mechanism, which is handled in C via delegates, events (multicast delegates) and the new async and await keywords that transform standard C into a lambda to be executed at compile time. It also handles multi-threaded asynchronous operations via it39s Parallel extensions, which permit spreading load across multiple threads/cores as long as that work is not serial in nature. Also, I would encourage you to check out a micro-ORM like Dapper. It39s far less comprehensive than EF, but it39s far more flexible and gets out of the way, plus it39s significantly more efficient than Hibernate and EF (about 5x faster for reads) Yes this article rocked tits. Esp good for a Croat with ESL ) nodeboy So after reading your article I still havent figured out why Node js want to reinvent the wheel. I still think node js and the likes are crap. A great introduction to find out what it is JavaScript and once the answer to from lta hrefquotgoo. gl/cfkytpquotgtbagaimana tips mengatasi wanita frigidlt/agt Noob questions: Um, isn39t the ease with which you can move request data (i. e. untrusted data) into database (where data is assumed to be trusted) a big hazard How do you ensure that you never forget to inspect every piece of incoming data when it arrives, before you start trusting it Generally, I would assume something as popular as Node. js would have thought of this, but I remember back when Rails had blanket model update. That changed real quick when Github39s use of this quotfeaturequot was exploited (fortunately, by a whitehat). Also, of course, just because you add a conversion speed bump does not mean that people won39t make mistakes, but at least they39re more likely to give it some thought, which probably means they39re going to make less mistakes. I don39t understand the angst against using an ORM. Were you in a proper environment where concerns were separated The ones bashing ORM just sound like they don39t know what they39re doing or how to engineer proper software. Why on earth would I want to go from writing software in Java/C/whatever to drop into SQL where it is hard to version, properly test, and can apparently cause severe brain damage Everything is a double edged sword - an implementation or a convention like using an ORM over raw SQL really doesn39t matter. Depending on the situation raw SQL might be best. it might be better to use a NoSQL store. maybe an ORM is fine Usually, from my experience, I can tell you that an ORM is better for a lot of reasons, and they have been relayed by M. I spent the time to write my own libraries to abstract vendor specific implementations and you need to create your own mappings. You can easily spawn from a certain state or use existing data structures. It took time to write my libraries and it was not easy at all to do it but it was well worth my time to do it since I can now reuse my libraries. Is it the BEST I don39t know. I like it but I certainly won39t go around to arbitrary technical articles that have nothing to do about SQL and post something like quotYes this technology is good but stay away from raw SQLquot I just don39t see a need to be bashing anything here, especially an ORM when the article is exclusively about JS and NodeJS. Probably one of the main points of this article, that gives Node is supposed scalability, is the offloading to a Queue or Service Bus that leads to asynchronous processing. That is a well proven architectural pattern, available in many languages, is especially used in CQRS (Command Query Responsibility Segregation) with Event Sourcing, is very well suited to be used by technologies such. Net Reactive Extensions that provide considerably greater functionality and flexibility than Node. Asynchronous programming and handling its pitfalls has been around without Node for years, if you had knowledge of enterprise development. As for the hate against ORMs. you guys crticising it seem to be moving from front-end development into an area where you have no knowledge or expertise in OO, BDD, TDD or any other proven Enterprise level methodology. No concept of integration other than Twitter feeds. No experience of complex Workflow or scalable caching. This is one of the dangers - you know JavaScript, and a bit of SQL. So everything else is superfluous - until you need it, such as the attempts to bring an element of type checking to JavaScript. Seriously, each technology has its place, but there is no one size fits all approach. Appreciate the strengths of each technology, and use them where appropriate. Great introduction to node. js Thanks, i samo naprjed Because they suck for a complex application. Sure if your scenario where you spent all this time trying to make the ORM work the way you need it to, you could have just put that same effort into writing the SQL properly and making sure it39s organized etc and you would be further along in the project and have more control over the application. ORM39s are great at saving time on a small to medium scale project, but once you delve into more complex and larger applications, you39re going to spend either A.) A lot of time coding to make the ORM work the way you need it or B.) Just decide to write the SQL yourself because the time it takes to make the tool work how you need it just isn39t worth it. Very great post you add JavaScript is better than some of the other programming languages. therefore lta hrefquotgoo. gl/L7tXeOquotgtcara menghilangkan gatal keputihanlt/agt better fit with JavaScript Great, informative article. Thanks for sharing this. lta hrefquotunlockpwd/quotgtUnlockpwdlt/agt Its very good post thanks Pot, meet kettle. Those may be intractable problems if any of them were true. None of them are: 1. a) JavaScript is all JIT these days and delivers 1-2x native code performance (faster than any other dynamic language I39m aware of). b) Non-blocking by default can deliver orders-of-magnitude improvements in code efficiency - transparently. 2. Almost all modern editors support type inference for JS. ESLint, Closure Compiler, and a number of other options offer sophisticated static analysis capabilities. TypeScript even offers a nice structural type system. 3. The opposite of modular is a tightly coupled monolith. That39s a bad idea in ANY language. 4. quotif all you are doing is waiting for some other IO bound processquot - Non-blocking by default means you39re NEVER waiting for some other IO bound process. That39s why Node delivers such huge improvements on resource utilization. 5. 2006 called. They want their language-snob attitude back. The days when serious engineers considered JS to be a toy are long since over. JS powers sophisticated enterprise applications at just about every fortune 500 today. Additional point: JS is the only language with fully native support for isomorphic code (meaning you reuse most of your application on both servers and clients). You can write JS ONCE, and it will power the server, the web browser, and mobile devices including iOS and Android. See React Native. leanpub/learn-javascript-react-nodejs-es6/ 1) 1-2x native code performance Do the electrons run faster on node code Not a good start. 2) Type inference is mapping variable declarations to types without explicit syntax, i. e. a) it requires actual types, and b) compilers enforce type safety, not editors. And you can dress it up any way you want, but there is no way to enforce sophisticated state analysis with slop-tastic dictionaries of whatever stored in strings amp functional delegates. Also, Typescript is not Javascript, it is Javascript with a half-assed type system pasted on top. Even Google is abandoning Js for Typescript in Angular 2.0 Why Because Google has decided that an untyped system is insufficient for serious work. But is that type system anywhere near as sophisticated as a compiled language Nope, not even close. 3) You are misunderstanding what I was characterizing as quotmodular designquot. The alternative is not monolithic code, but encapsulation, specialization via inheritance (or prototyping), polymorphism, and externalizing dependencies via IoC. The alternative is SOLID, i. e. modern Object Orientation. 4) Your process may not be waiting, but your customers are waiting for the callback. My point is that being able to serve more requests doesn39t do you any good if every served request then has to wait on yet another operation. In the end, somewhere somehow, you will eventually be going to a disk or waiting for IO, because that39s where the information the customer wants lives. 5) I didn39t say that JavaScript was a toy language, I said that most JavaScript developers are well-meaning, cut and paste amateurs, and they will invade the ranks of node. js developers as it becomes more popular. I39ll take a strong type system over quotfull native supportquot (that39s not native) for quotisometricquot code that can run on clients or servers you say that like that39s a good thing any day. Wow, Js on android and iOS I guess the days of Apple adding another strongly typed, native language for iOS are overlt/sarcgt Obviously you39ve never heard of Mono, the cross platform. Net that compiles and runs on every major OS, produces native runtimes for all three major mobile platforms, and runs on everything from beowulf clusters to wearable devices. This is why we don39t respect you. You don39t know or understand anything that came before, or anything outside of your javascript bubble. You don39t solve any problems that weren39t solved before, but yet you39re convinced you have all the answers. That seems to be a common theme with anyone whose education system stressed self-esteem over critical thinking. This reply just strikes me as willful ignorance. 1. Really Rather than investigate and learn the truth, you just want to ridicule the answer I39m not taking the bait. Watch Brendan Eich39s Fluent talks if you39re interested in actually learning something. 2. I know what types and type inference are, and I know the benefits of static types. I39ve been in this game since before JavaScript was invented. TypeScript is a superset of JavaScript that compiles to JS amp allows for sophisticated static analysis. It39s structural type system is better than the type system Java had back when I was coding in Java, and it39s much better (as in more reliable and flexible) than C and C. 3. quotencapsulation, specialization via inheritance (or prototyping), polymorphism, and externalizing dependencies via IoCquot - these are all forms of modularity, and JavaScript modules provide viable alternatives to all of them - and in the case of class inheritance, it39s far superior. See medium/javascript-scene/the-two-pillars-of-javascript-ee6f3281e7f3 4. quotyour customers are waiting for the callback. quot Fortunately, that39s where the performance I talked about in point 1 shines. JS provides efficient utilization of I/O resources. In fact, dealing with I/O bottlenecks is the entire reason that Node was invented. I39ve ported several large production projects from PHP and Ruby to Node, and seen dramatic reductions in response times, both average response times and response time ranges - and since a typical Node app utilizes a small fraction of the memory required for C applications, your customer I/O competes less with the RAM paging you might experience with a compiled C application. 5. quotyou say that like that39s a good thingquot I39ve seen objectively measurable increases in team velocity ranging from 40 - 60 improvements. Believe it or not, it39s a fact, and being more able to adapt to changing needs and experiment more (particularly in the UI layer) delivers very real business value. Why do you think so many enterprise organizations are adopting Node It39s not because some dev prefers JS. It39s because they ran the tests themselves and figured out it39s a huge win. quotObviously you39ve never heard of Mono, the cross platform. Net that compiles and runs on every major OSquot Yeah, I have - what I haven39t heard of is Mono delivering anywhere near the value that Node delivers in enterprise production. Got a good article on that 39Cause a quick Google search isn39t turning up much. Check out this awesome result in the top 3 of the SERP: quora/Why-isnt-C-with-Mono-popular-for-enterprise-applications-on-Linux-servers. but a quick Google search for Enterprise Node. js delivers quite a bit. Here are the top 3 search results I see: blog. risingstack/node-js-is-enterprise-ready/ joyent/nodejs-support centurylinkcloud/blog/post/node-js-is-taking-over-the-enterprise-whether-you-like-it-or-not/ There39s really no contest here. 1, yes, I39m mocking your evidently accidental claim that JavaScript makes electrons run faster, or even as fast as native, because it39s patent nonsense. Not only is that impossible, it ignores one of node. js39 acknowledged weaknesses: It sucks on compute intensive operations, because it39s single threaded, which means compute intensive operations block execution. duh 2. Your knowledge of Java does not qualify you to understand what a competent type system is. Java39s generics are a largely useless, johnny come lately me-too feature when compared against to C generics because they suffer from run-time erasure, in other words, the generic type safety and reflection only works at compile time, because at run time, everything is cast to an object. So when you are going on about static analysis, you are effectively trying to claim it39s as good as compile time run time type reflection, which is very far from the truth. 3. Meh. Chopping up everything into discrete functions is a form of modularity too, but it39s vastly inferior to SOLID, which was my point in the first place. And while prototype based inheritance is interesting, it39s hardly better than real inheritance, which permits far more flexible arrangements. 4. I don39t see how it39s impressive to speed up a Ruby app, or refactor some craptastic PHP into something faster. Your memory overhead claims are equally baseless: I can run micro. Net on a watch or on an arduino device. I can write. Net that runs very well on an under-powered phone. Look at the memory chrome consumes for an SPA, or try to run a complex javascript app on a tablet, and then tell me how quotlightweightquot JavaScript is. 5. The lack of a proper separation of concerns (which is the cause of most maintainability problems) is the number one issue I encounter at enterprise scaled customers, and an impressive team velocity is always how they got there. Why do I think a number of organizations are choosing node Because typically a mediocre, over-sized team of moderate competence f39d up the previously shiny new thing that was supposed to solve all their problems, so they want to believe the hype that the problem is not them, but their previous technology choices. 1. I think you misunderstood my meaning. JS runs 1-2x SLOWER than native -- much better perf than any other dynamic language I know of. It39s fast enough to run AAA game engines like Unreal Engine and Unity in stunning quality at 60 fps. 2. I actually think that a good native type tool would be a good addition to JavaScript, but only if they39re user-definable structural types. That said, JavaScript does support static analysis via type inference, and there are a number of ways to provide type hints for dev tools. In addition, JavaScript also has an impressive array of runtime analysis tools. 3. quothardly better than real inheritance, which permits far more flexible arrangements. quot Wrong. medium/javascript-scene/the-two-pillars-of-javascript-ee6f3281e7f3 4. My apologies. I was not aware of micro. Net. JavaScript also runs as-is on low-powered devices including Arduino, Tessel, and a number of others. Node works great on most of them. If that39s not small enough, you can create a custom Node compile, drop features, even swap out the V8 engine for a different JS engine if you need to. You can also restrict yourself to using tiny JS libraries (of which there are many on npm) to keep your codebase compact. 5. quot. they want to believe the hype that the problem is not them, but their previous technology choices. quot That might explain an experiment or two, but the Node takeover is much more than that. We39re rapidly replacing apps in a variety of languages with Node. Having worked at a fortune 500 during the transition to Node, I can tell you our justifications: We did experimental ports to Node, found: 1. that the app was faster and more reliable, delivering huge wins in both average response time, and the number of requests we could serve with the same machine, and 2. The developers were more productive for a variety of reasons, including the fact that JavaScript specialists could more easily work on both sides of the stack without context switching, and a lot of code could be shared in both the server and the client. Those advantages have real, measurable influences on the company39s bottom line. That39s why Node is taking over at both startups and enterprise companies. especially with edge it is really handy Thanks Tamisalv I was looking for quick reference read for understanding node. js and why projects might use it. Reading this gave me a better understanding of advantages of this this technology and also when one might use it. Cheers quotAfter over 20 years of stateless-web based on the stateless request-response paradigm, we finally have web applications with real-time, two-way connections. quot As a result we have webpages which take longer to load nowadays when we have Internet speeds in the order of megabytes per second, than back in the day when our speeds were in the order of bytes per second but our webpages were plain simple HTML. Nowadays we have webpages which load halfway and then stop, which crash at the slightest network error i. e. dynamic IP address reassigning, or a momentary lapse in the WiFi signal forcing you to reload the whole page, whereas browsers are designed to gracefully handle those errors or resume once the network connection is restored, buggy Javascript scripts don39t handle errors as well. I only have 1 question here with your statement. quotIt39s structural type system is better than the type system Java had back when I was coding in Java, and it39s much better (as in more reliable and flexible) than C and C. quot I can not take that. How can you examplify Some Facts (with obviously answer in no) - Why did Node inventor used V8 engine which was made in C to power node, if the js type system was so flexible and much better - Can nodejs decode vp8 codec video by itself as efficiently as C/C - Could you build nodejs on top of pure javascript instead of C - Is there any such thing as pure javascript You really have to understand my friend that it is a type system that can take advantage of underlying hardware and makes your program efficient at CPU and memory. Strongly typed C can solve any problem, even build node js. Node shines at non-blocking i/o and that is about it, it can not do anything else. Yes you can chop-off node code and make it work on micro devices but will it be efficient and make sense Can you make product like node where you have to code in C, yes you can but it would not make sense as power of C/C in not in web, its optimizations and hardware. It not like non-blocking I/O is something new, we have had that in many technologies including java. Net, basic, python and perl, this is very old. The only reason why this thing is in limelight is it has enabled millions of frontend javascript developers, who do not understand pointers and bash about C, to write server code, which is simply overwhelming, that39s why the buzz. And about quotNode in particular are actually very well suited to handle distributed computationquot, why on earth one would write such a statement Node is not made for computation. it can not compute as efficiently as C/C/Java. Período. With all due respect, lets not bring C in picture here, there is simply no practical comparison at all, or it will be very touchy. You may be interested in this: medium/javascript-scene/what-is-webassembly-the-dawn-of-a-new-era-61256ec5a8f6 Actually, Javascript in the V8 server engine is QUITE fast. The statement that Javascript is not fast is outdated. You combine Node with Chrome and you get a very fast environment. If you understand how Node works, it has an event loop that processes all code that is ready to run. So, you call a function that has a blocking database call inside and a callback when finished, it allows the the function to be called, which returns immediately allowing you to get on with other things while the database call is being processed. So you aren39t quothurry-up and waitingquot as you suppose. You get on with other things, and once the database call finishes, execution will continue to the callback which is invoked after the database call returns. So, you get the same basic abilities as a multi-threaded environment without all the extra overhead incurred by thread-state swapping. Because you don39t get quottime slicingquot you have to be careful that no piece of code takes too long to run, and if it does, you just break it up using packages like quotasyncquot. I come from a long C, C, Delphi, Java background, having mastered the multi-threaded paradigm, and I can state assuredly that the Node single-threaded async paradigm is super cool, fast, and highly scalable. IF YOU KNOW WHAT YOU39RE DOING. But that39s the same for any of the other technologies as well. None of these technologies are for neophytes. A complex application is precisely where well tailored Domain objects and properly decoupled subsystems are most necessary. If you are spending all your time trying to get the ORM to work you should either learn that ORM better or get another ORM. I would assume the former goes without saying so if you are still fighting your ORM it39s time to choose one that just works. Excepting your last comment that these technologies are not for neophytes, I think you are ignoring the last two paragraphs you were responding to. Even the founder of node. js says to avoid compute intensive operations. Yes, V8 speeds up javascript, but that doesn39t solve the problem of a compute intensive operation or IO dependent operations blocking a single thread. You then respond that node. js is non-blocking and therefore it can be awaited. Great, I got that, sure, but what are you waiting on Some code that isn39t written in node. js apparently, (so much for the claimed benefit of quotone true language to rule them allquot), because your single threaded node. js process is happily moved on to something else until the callback. So, node. js works great just as long as you can rely on other processes handling the workload that is blocking (like waiting for IO), or another instance of single threaded node. js, that will (if written quotcorrectlyquot) undoubtable kick the can down the road to yet another process. And that39s the issue: there are a limited subset of stuff done in programs that can be executed in parallel/out of order, and/or doesn39t rely on blocking operations. Multi-threading is more complicated and has some overhead every time there is a context switch, but it means that more cores can be thrown at parallelizable units of work, and even discrete operations can be handled by the different threads. In a quotnode. js solves everythingquot world, you are either relying on something not written in node. js or waiting for your single threaded node. js application to finish up all the stuff that must be done, one way or another. You know what You seem to just like spouting on about something you are clearly not qualified to speak about. You obviously have never built anything serious in Node. js. Well, I have, and I can tell you that it works great if you actually program it correctly. That means you use things like job queues, you use the clustering that Node provides, you make sure you do everything with callbacks and promises, you use quotasyncquot and quotsetImmediatequot to properly share the processor between code that is waiting and code can now execute, you make sure UI code has priority over CPU intensive code, etc. For example, I wrote an quotasyncquot heap sort algorithm that works great, sorting massive lists while not blocking for any appreciable amount of time. I also have a 5000 line heuristic algorithm that is quite complex that I split up so that the main loops are executed using async constructs. I then have these executed from a job queue called quotKuequot that allows for efficient use of all cores, no threads, great UI response time, and complex calculation jobs being executed in the background using all available processor power. This is ALL done in javascript with excellent performance in both CPU intensive tasks and response to front-end data requests. In other words mate, the UI is super responsive, and the background processing (complex heuristic calculation) performed quickly and very responsively. This is all done with a single language for both backend and front end, which is a huge deal when it comes to system architecture. Why are they not for quotneophytesquot Is it alcoholic I agree. Most times that I think an ORM is inadequate for complex queries, I write out raw SQL, later to find out the ORM has an quotapp for thatquot. I like using an ORM as much as possible, but I won39t spend too much time making it work for me, otherwise, as M said, I39ll find another ORM. Sounds like the words from a quotMichaelquot I know. ) I agree with your last statement. quoteach technology has it placequot. But why do you assume all Node developers are front-end developers with no back-end knowledge Why is it NOT possible for these developers to make a scalable solution Like or not Node is being used in Enterprise today and will continue to be adopted. Javascript is a poor choice of language for enterprise/complex development. It is messy, difficult to read, difficult to organise, doesn39t support an entire raft of OO paradigms that save a lot of code repetition and provide readable abstraction, predominantly gives run time errors, no AOP, no by convention, no reflection, no generics/templates, no precision of scope, no rich low level processing, and it is not type safe. We are stuck with it in the browser, and frankly it is only inertia and legacy support that means it is still used there. In all rights it should have gone the way of the dinosaurs 10 years ago. The main driver to move away from scripting languages was that they were a maintenance nightmare and led to ball of mud applications that had constant bugs that couldn39t be tracked. It has only been a short 10 years since we breathed a huge sigh of relief when serious development moved off of scripting languages and here we are doing it again unwilling to learn from the past, convinced that this is quotnew and cutting edgequot, rather than just old, tired and regurgitated. It will end up the same way as it did last time, being talked about with disgust like classic asp and perl cgi. I can only conclude the developers championing it now were just not around to see the fallout of this last time around. Every new generation of developer is convinced they have discovered quotthe truthquot, those of us who have seen this cycle of pain just have to sit back and shake our heads in disbelief. Unfortunately you can39t teach experience, it is something you have to learn the hard way. Sure if you are an amateur and know nothing else then by all means, but anyone trying to do a professional job needs to leave this alone and stop making populist technology choices without considering the outcomes. If you can39t evaluate the long term limitations of a technology for yourself you shouldn39t be working in development. Developers need to stop being so childish, acting like a bunch of deluded fan boys, this is a serious business, not a game. DIOS MIO. Eric. Are you for real Do you even know how Nodejs works Did you even try to look at backbone of Nodejs Just download yourself a source-code and checkout. IT IS IN PLAIN C/C. httpparcer is C lib. libuv is another and single most important C library in nodejs backbone which makes nodejs async, event driven and non blocking. Javascript by itself is body without a soul and life. JAVASCRIPT is just a script that you use to script your logic. One day if smeoene ports lua with this libs, he will not need Javascript to code. same for python etc. But the basic fact remains the same. IT IS C code that makes what nodejs is, not that javascript is too fast. in fact javascript is slowest in all of the scripting language. So don39t flatter yourself in believing that just java-script is great and other things are shit. And do not insult C/C if you have no knowledge of it. So, again, i urge you to take back your words: quotJavascript type system is better then Cquot. (Javascript has no type system. and if you still believe that it has one, you are in a very wrong field, go build some scaffolding) Also, these companies are not choosing nodejs for the reason you mentioned. This is possible in almost all languages. The reason why companies are choosing nodejs is that, they get ready made javascript coders, which are in millions and can not do c/java code, to do server side because it is cheaper. Another reason - gt its ecosystem. Yet another reason - gt Its lot easier to conduct load tests in nodejs than other scripts. The link you mentioned is work that is intended to be started. Why do not you suggest them that please write this web-assembly compiler in nodejs rather than c/c/assembly because according to you that is superior. C39Mon man, how can you compare Nodejs (A technology) with a C (language) they are not in the same league. C makes node possible, its not visa versa. quotThe main driver to move away from scripting languages was that they were a maintenance nightmare and led to ball of mud applicationsquot -- could you clarify what you mean by scripting languages, and what replacements quotserious developersquot migrated to over the past ten years I was pleased to see a reference to Django in the article and have not run across maintainability issues caused by the use of Python, SQL, or ORMs in general. On the contrary, Python is my go-to language precisely for its maintainability. Your criticisms of js are spot on, but I can39t see how they apply across the entire universe of scripting languages. Well I define scripting languages as runtime compilation languages, but there is a lot of overlap these days. I prefer the reassurance of compile time verification of at least coding accuracy but that is not the only factor. The depth of invasion into the inner workings of the compiler that tend to be exposed by compiled languages these days allow for a whole range of design constructs and patterns that allow programming to be more quotintelligentquot, I just don39t find this level of sophistication in the scripting languages I have used. It is a severe limitation for serious enterprise development. ORMs are an ugly approach to data access on relational databases, but you would probably have to be a database developer to realise why. Data design and Program design have different constraints, ORMs do either an injustice or have to be modified so much that they provide no productivity. There are many issues such as security, isolation, atomic operations that ORMs break, and remember a database is a living system and may require changes in between code releases as a matter of course. ORMs are a blunt tool if you want real performance from your database and want high concurrency without locking. Its a detailed subject I could probably write a book on it, so sorry if this isn39t conclusive enough for you. Can39t say much about Python other than I have heard good things in general. I39m the other end of the market on. Net, I crucify the open source guys next door in productivity and my defect level is about 1 of theirs. I think you need a large system before it makes significant differences, as you need to invest in framework and substrate to get the main benefits back, its quotmass codingquot that is the enemy here. When you have over a 100,000 code files you need a higher level of maintainability as it is simply beyond human capability to do it file by file (and certainly beyond maintenance budgets). By making core services that consume code as content you can achieve a high level of quality while keeping everything granular and ensuring release are small and targeted rather than entire system drops. Each to their own, but if you are an IT pro you must have seen the millions of script based systems festering away in businesses because no one can find anything or understand how it works. It39s such a common complaint I should think it doesn39t need justifying. PD I think quotserious developersquot have migrated to either Java, C or back to C (along with their associated web techs etc). I wasn39t really intending to be derogatory but these three probably account for 90 of all commercial development atm. C wins out on the commercial front for me solely on Microsoft39s considerable ongoing investment and new found modernist approach. C is not very productive and Java is really starting to look a little dated. Still I work in all three and they get the job done, each have their place. P. P.S. quotPython is my go-to language precisely for its maintainabilityquot. What do you consider maintainability It is often not what people think it is (or is not as simple as they think). It encompasses the cost of change and that is the primary cost on the business for a living project. Example: I have a service with 1000 public methods and the business asks me to de-prioritise all calls that take over 2 seconds. If I have to modify any of the code in those 1000 calls then my code has seriously poor maintainability. What I should be making is one code change in my service substrate pipeline. I should not even be modifying the substrate I should be probably writing a statistics module and a de-prioritise module for that substrate loaded in a separate dll that can be loaded dynamically. Now my testing is isolated to just this dll (reverse harness testing) and when ready for release I can add this dll and maybe make one small config change, that39s it, no regression testing and no risk to existing code, so no production bugs in the service methods. So many typical code bases would require all 1000 methods to be altered or at least marked for an AOP operation. Enterprise design requires upfront anticipation of future quotcrazyquot business requests. I find with most scripting languages and even with Java that finding insertion angles later on is nearly impossible. Even if I have a complete mare in C I can emit the code directly into the methods using reflection, I have never seen this level of access on a scripting language and even if it was there it would be dangerous code to emit into runtime compiled operations (because I am literally changing the operations content so I would need to test the result of each). This is just one example I could probably come up with 100s. I39m a technical architect (framework and substrate) so it is my place to quotsavequot my devs from backing themselves into a corner. If I do a good job I can reduce the coding and testing effort to 1 of a quotmass codedquot system. There is a whole other level of development that most devs will never see or appreciate, this means they are never equipped to make the most appropriate technology choices. Interesting article, I39ve got quite a bit of experience in other realms but I39m somewhat new to Node. js. There39s a few things I39d like to clear up: Flash was always async as well, it merely emulated threads much like it sounds like node does by using an event queue. However, I believe it is technical ignorance to claim that trusting thread management to a 3rd or 4th generation language would be better than trusting a well-tuned JRE or operating system optimized for it39s multi-core chipset. How exactly do you think threads work in the lower levels anyway It isn39t some quotmagicquot, the only way to get true simultaneous code execution is via multiple processors, something you simply can39t accomplish with a single thread. It39s also a mistake to say that a new quoteventquot does not add memory or clock cycles taken to a stack just because said events are managed by an interpreted scripting language rather than optimized, compiled C. I39d bet my lunch that a well-written multi-threaded web application written in C or C will blow away any node. js app performance-wise, and that39s even without getting into servers and their current multi-core processor architecture. If you39ve got a quad or 8-core server running a single node thread. you39re only firing on one piston (quite ironic that Google calls their engine quotV8quot when considering such a fact). Another thing to realize is that while Flash (or even Java applets) ran in their own runtimes, so does node -- it39s just hidden to the user. That is nothing more than quotgoodquot (perhaps hostile) business moves on Google39s part. Lets be honest here, if all browsers came with Flash automatically installed on them, and Apple actually supported Flash on their mobile devices, node probably wouldn39t even exist today. I have other concerns about security. What kind of protection does it have against cross-site scripting and other attacks Earlier today I stumbled across a TOR/Bittorrent client that ran in my browser window, and after opening it my computer wouldn39t shut down nicely (it scares me to think what it could have been seeding). No warnings about security or what types of connections my browser window was opening up, just went along with it39s P2P business. the hacker side of me could have a real hay day with those kind of quotfeaturesquot. I doubt that kind of stuff has been tested much either which means there39s a lot of room for bugs, and where there39s a lot of room for bugs there39s a lot of room for vulnerabilities. But hey, at least your entire stack is all in the same language Means you can hire less experienced developers for less money, right ) Good Article for Node JS, you can learn Node JS online in iwebworld. info or send a email iwebworldinfogmail You could remove all the pitfalls of JS by using the its superset aka TypeScript. Tldr Use node for IO-heavy processing and delegating CPU-intensive processing to a cluster of specialized worker nodes (ex database, media processing, etc). This isn39t exactly new information. I covered this topic back in 3912: programmers. stackexchange/a/179499/1256 Ideally, the HTTP and API servers should be mostly stateless (excl session management) and disposable. They39re just a functional pipeline that translates the raw data into consumable representations. That way, the servers are easy to provision/destroy dynamically to meet the spikey nature of demand. I39m not sure why so many of the commenters are vehemently arguing in favor of multi-purpose vertically-scalable server architectures. By nature, vertical scaling will always have an upper limit predicated by hardware capacity. No matter how efficient the code is. The writing is on the wall. You can spend a fortune on hardware and lose sleep questioning the validity of your risk assessment (aka WAG). At the end of the day, bare metal is a fixed asset. Best case, it meets expected demand and justifies the cost. Worst case, it either costs more than it39s worth or lacks the capacity to meet demand. Alternatively, you can embrace distributive computing and automate the infrastructure to grow/contract relative to demand. For the people fighting religious wars over which language is best, node C java. Who cares. All 3 allow 39functional-style39 programming. All 3, support async processing (natively or through extensions). All 3 can be managed via provisioning. All 3 are perfectly valid for building distributive infrastructure. Choosing which one to use depends on the quality of the tools, whether or not it will be used to extend existing infrastructure, and the perception of the client. Build whatever you39re good at building. If you39re really good build whatever is easiest to implement, support, and generate the most profit (or save the most on cost). BTW, kudos to the author. It39s nice to see somebody do a comprehensive (and mostly objective) writeup on this topic. Yes, both languages support horizontal scaling with asynchronous message management infrastructure. CQRS is nothing but an API implementation pattern. CRUD is the typical use case (as it should be) but Node doesn39t automagically scaffold 1:1 mappings between DB and CRUD (see rails/laravel/django for that). Node isn39t a framework at all, it39s just a HTTP server. You can leverage frameworks (ex Express) to more easily leverage the full power of Node but you still have to fine-tune your routes to define a fully functional API. Net Reactive Extensions have been ported to JS: npmjs/package/rx In fact, even LINQ has been ported to JS (yes, seriously). linqjs. codeplex/ ORMs are only an issue because they require an additional layer of abstraction from the underlying data. If (read when) the data models need to change to adapt to business demands, both the ORM and the database schema will need to be updated and tested to reflect the changes. Which is not really a big deal if there39s a good update strategy in place. As for the rest of your comment, you39d do well if you stepped out of your comfort zone once in a while to see how JS development really works. 1. JS classes are currently supported now via ES6 (also, available client-side via polyfills). Prototypes really aren39t much different than classes in terms of encapsulation (except they39re a lot more flexible). Compile-time static type checking is even supported via TypeScript/Dart if that39s what floats your boat, it39s just not the default. 2. TDD/BDD isn39t a feature exclusive to statically typed languages. There are a lot of great testing frameworks available in JS (both server/client-side). Choose your flavor, unit testing (Mocha), behavior driven unit testing (Chai), api testing (SuperTest), and continuous integration testing (TravisCI, and many others) are all used extensively throughout the community. JSUnit (the JS equivalent of JUnit/NUnit) is even available if you miss unit testing in Java/.NET. If anything, testing is a basic requirement of any non-trivial JS app that goes into production because you don39t have a compile-time type checker to hold your hand. 3. Complex workflow Seriously So, you39ve never heard of NPM scripting, grunt, gulp Automating any-and-everything in JS is pretty easy. Style enforcement, linting, documentation generation, scaffolding, one-click-deployment, language transpilation, bundling, distribution building, package/dependency management, release management, etc. 4. cringe: if you rely on the compile-time static type checking system alone to validate user input, you39re doing it wrong. Building a data layer in any language requires constraints above-and-beyond what the default types provide. So, either way you39ll have to extend your data models with custom validation checks. The cool part about handling validation in JS is you can use the same routines to check user input on both the client/server-side. Less duplication of effort FTW. Contrary to what you think. Javascript really is a 39one size fits all39 approach if you prefer to use it as such. Seriously, you can even compile C/C directly to javascript using asm. js. Does that mean you have to use it Of course not. Any developer with a speck of sense wouldn39t fault you for choosing C, it39s a great language. I have experience writing code in many languages, including building non-trivial desktop applications in C. Given a choice, I39d prefer to use Javascript. The mix of, looser constraints and functional/imperative/prototype styles allow for a level of creativity I haven39t experienced in any other language. The tools are great, the module system is amazing, and the language itself is getting substantially better with each update. Upload Files: howtonode. org/really-simple-file-uploads quotAll the I/O operations is handled by Node. js is using multiple threads internally it39s the programming interface to that I/O functionality that39s single threaded, event-based, and asynchronous. quot stackoverflow/a/22981768/290340 Libuv uses a thread-pool to handle I/O operations (files, sockets, etc) in an asynchronous manner. Where most languages block by default during CPU-heavy I/O operations, Node doesn39t. It simply fires an event when the I/O operation completes on the worker thread. Active Directory: github/gheeres/node-activedirectory github/auth0/passport-windowsauth The distinction is that Node is async by default So, the number of developers doing async programming in other languages are the minority so they39re not as well represented. quotI can39t come up with any good reason to use it on the server side in favor to other available languages. quot Not gonna lie, using Node at first was. Challenging to say the least. Getting used to async-by-default is not an easy transition. The nice part Node is, the primary focus of the platform is building servers/clients so the ecosystem has a lot of powerful tools to do anything dealing with web development. Quot. have better standard libraries, tools and resources. quot I39m not sure what gave you that impression. It doesn39t use the monolithic-everything-and-the-kitchen-sink base class library approach. The core itself is very small but that39s a benefit as it39s much lighter to deploy. It also includes a very powerful, full-featured package manager by default so you39re expected to add the dependencies your project needs. NPM (Node Package Manager) has over 200K packages and counting. Since the majority of the modules are developed independently from the core, they iterate and improve much faster than the equivalent core libraries in other languages. Dependencies are managed locally on a per-project basis in the package. json file. Typically, it39s bad form for a module author to require that their package be installed globally. Installing packages locally prevents version conflicts at the global level and guarantees that -- when you install a package -- everything required to use the module is included. It may seem inefficient at first glance because many dependencies may have copies of the same sub-dependencies (or sub-subdeps, etc) but compared to the cost of including a massive standard library, the storage space is insignificant. The workflow to setup a project is: - clone the source - run 39npm install39 NPM will automatically download and install all of the dependencies (incl sub-deps, sub-sub-deps, etc). Since the dependencies (and their specific versions) are explicitly defined in the config, you don39t need to check them into source control. In addition, with ES6 (incl the new ES6-module-loader) about to be released, a new JSPM (Javascript Package Manager) has been created to manage client-side javascript dependencies. Module imports in the browser have finally been formalized in the language spec, so Bower and the variety of module-loading pseudo-standards (ex AMD, CommonJS, UMD) will go away. As said above modern OO languages have a vast array of options to formalize and control your code and solutions that are lacking in scripting languages. That39s just the plain truth, no amount of griping is going to change that. My point is there are a lot of developers choosing technology by popularity rather than suitability, that39s what makes them fan boys. Right tool for the right job, applies in every trade apart from software development apparently. But that is probably because most developers aren39t true quotTradesmanquot, more glorified quotDIY39ersquot. The industry is full of amateurs who don39t even know enough to know that they know nothing They think because they can write an if statement and a while loop they are pros. Techno-weenies. System level I/O operations (such as files, sockets) in Node are handled by libuv which does use a background thread pool. The difference is, the main thread can fire and forget the task to a background thread and the background thread will notify the main thread (via firing an event) when the operation is completed. Even with background thread processing, doing lots of I/O operations doesn39t scale very well. For long-running CPU-heavy tasks (ex image/movie encoding) offloading the tasks to worker nodes is still preferable. In most languages, I/O operations are handled in a synchronous manner so if they requests are made on the main thread, they39ll block execution until completed. The reason you don39t see a noticeable pause in the UI when this happens is because the UI is asynchronous/event-based and runs on a thread separate from the main context. There39s nothing stopping you from exposing the API as a microservice. WebKit just allows you to run a native JS client. I may be wrong but from what I understand, unlike the browser a webkit client isn39t as strictly sandboxed so you can make system calls (ex to open/save files without user input). I think you made my point for me, frothing unthinking, emotional nonsense, with very little in the way of fact, from a mind so fanatic about one thing it can39t even see its failings. You seem to have made a fair few assumptions about what I do and don39t know, I have been doing Javascript for 20 years, I know its short comings, I can work effectively in probably 30 languages, I use what is appropriate, I never indicated otherwise. You need to grow up or find a new industry to work in. People like you are the problem with Software Development, no nothing nobodies who can39t even make a case for a technology, let alone use one. Please stay away from the keyboard and do the rest of us a favour. Do you use version control with a standard workflow (ex Gitflow workflow) where developers make changes on feature branches and code is peer reviewed before being merged I39ve been messing around with trying to build an Angular2 website lately and the Angular2 project is still in early alpha so breaking changes are a regular (albeit unfortunate) occurrence. All of the available examples online are pretty-much broken so I39ve been monitoring the project development on Github. The rate that the core developers are thrashing on the codebase is truly remarkable. What39s even more amazing is that every PR is unit tested and continuous integration tested well enough that every release is guaranteed to be fully functional (as far as they39ve implemented it so far). Following what Tracker1 is saying. Linting is the equivalent of compile-time checking in JS. I even use a Sublime extension that shows linter errors directly in the gutter of the editor as I39m writing code. If you want stricter checking you can add a style checker such as 39semistandard39 which guarantees code styling on a project-wide basis. That means, spaces-not-tabs, indent 2 spaces, consistent functions, curly braces, etc. Type checking is good for superficial bugs (ex uninitialized variables, dead branches, invalid values) but eventually you39ll have to verify the code doesn39t have logic bugs through unit testing, continuous integration testing, api testing. Node uses async event-based I/O via libuv (incl a thread pool reserved for I/O requests). The main thread absolutely does not block during I/O operations. It works the same way cluster would except it39s built into Node. Check out one of the presentations on libuv for more details. Performance wise, PayPal seems to think good things about Node dongnotes. blogspot/2013/12/paypals-nodejs-versus-java-benchmark. html For security, the 39cors39 module is pluggable to Express and can be used for all the usual CORS control stuff. The 39helmet39 module -- also pluggable to Express -- exposes a small suite of features to protect against malicious users including additional cross site scripting protection. I39m not sure if I39d call a Fullstack JS dev 39inexperienced39. Having a solid understanding of multiple domains in a development ecosystem that is constantly evolving is maddening. ya know, quot10 years of experience vs 1 year of experience 10 timesquot. Node. js hasn39t even been around for 10 years (which is funny considering I have seen job postings actually asking for 10 years experience with it). I understand that following evolving technology is a challenge, and after 20 years I can tell you that by the time you get completely comfortable with any quotfull stackquot it will be less relevant because technology is always advancing. Nothing will change that, it39s just how things work. However, you can39t really have your cake and eat it too there. Newer technology is less tested and therefore less secure, but older technology does not have as many features. There39s always a trade-off there. Anybody who claims otherwise is selling you something. I am sold on Node. JS (if your application is into building high scalability networking applications), Node. JS is the way to go in 2015. No wonder why so many startups and large corporations are adopting it. C, Java, Ruby and Python havew their place in their respective domains. New companies and products will be getting built on wide variety of languages. I predict ROR adoption would still be high in coming years for building web applications (simply because ROR developers are easily available and time to market is so small). Excellent article though Tomislav. So true My job is the maintainance of legacy apps usually SQL Server dB39s ms access or pop fronteds. These were usually made by quotthe grandson who is good with computersquot Kind of guy. No foreign keys, but custom date time functions. Your post is my sentiment exactly I find Java very unproductive and very expensive for a lot of low level tedious work. C is for programmers who can handle memory access/pointers. Most corporate programmers cannot. Back in the day you had PL/1 and C for software engineers and COBOL for information technology programmers. Gracias. this is so helpful as i am going to make a heavy-computation enterprise application. i think i39ll try node. js on other application. for now, i39ll use ruby on rails When this article was written Thanks for this article I think than the argument of same langage for front and dev is the worst I can liste or read. Organized good coding with js is the more horrible things append in a team. I work since last year on backend project and where this should be coded in some times with mature framework like django it took too much time understand hundreds bugs. Where mongodb feels cool. Nunca. I realy thinks than nodejs is a big joke and not So cool. The package manager give us some cool package to patch and hide the bad side of node but there is nothing to do about the callback hell. Finally the code looks like a big sand box than i hatte to open a file for debug or add some lines of code. So my conclusion is than for small app why not but for big and evolutive project not use nor nodejs and mongodb. Regards This is a fairly ill-informed comment as ES6 was alive and well as at a year ago. Besides the OO from ES6, there is also TypeScript which adds even more enterprise-level OO to JavaScript. Like. NET is compiled, TypeScript may also be quottranspiledquot to Javascript. NodeJS allows for pretty much of all this now with an even still better utilization of server resources and no OS lock-in. Think cutting your infrastructure costs by 2000 because you really shouldn39t need to scale too vertically or pay for that. NET license per node. Fintech companies like Paypal are happily doing great things with node as well so I highly doubt this comment of yours comes from a place of non-ignorance about what NodeJS eco-system truly offers the enterprising product. I really wanna be able to try out Node. js but it39s such a pain in the effing ass to get something running. Installing a quotsimplequot app always turns in to a list of things you need to do, install shit globally (which is NOT always possible), edit files, try to figure out what the damn devs mean in their scant instructions. It quickly goes to shit if you do the slightest thing wrong. If it39s so great why hasn39t anyone figured out a way to make simple installers with this thing Ghost blogging platform github/TryGhost/Ghost/blob/master/package. json David M Tromholt Yeah it would be nice with a date. I assume they don39t show it because they know how biased people are towards new information but it doesn39t make much sense to hide it in an article about a fast growing technology. Hi Avinash, Can you please eloborate little more on your statement. I am trying to understand more on this. Would node be a bad idea for something like 9gag then Would you need to do any image manipulation on a different server to prevent blocking Hey Tomislav, Great article I wanted to know that if suppose I want to get external hardware output in my app, e. g, scanner or e-signature (if user is doing e-signature or getting scanned copy from scanner), then can i get directly in my app it will be like an api call as we do in Java. TypeScript is syntactic sugar wrapper on top of standard JavaScript and compiles into standard JavaScript. It is invented to make the code maintainable and allows it to be used more like a real programming language. Given that you have to use JS where appropriate it makes writing it more familiar to real programmers and makes it maintainable. That said, anything JS and Node is appropriate for thin, lightweight web apps that need to be put together quickly and efficiently, for which things like ASP. NET, JSP, Ruby etc are a bit of overkill. Believing that one can not use the new magic Node for everything just because one guy can write front and back end is amateurish. Encapsulating a language with another language, which you have to translate will add overhead. Also there are things that don39t translate, just in real life translating between language, you loose something. In this case you loose speed (having to translate from one to the other), and optimization, because of reason one. ORM39s don39t do it all. In the beginning, I was for ORMs, then I dove deep into it and you end up with quotHow do I do thisquot, quotOh you can39t easily, you have to do 10 other queriesquot, or you end up with stuff that just seems like it should work well, but you end up wrecking the performance. ORMs are for simple quotSelect blah blah from table where x yquot. Hey, is there a library/tool you used to creste the graphics