Atma Node.js Server Module

• Overview

• Application

• Configuration

  • Resources
  • Routing

• Endpoints

  • Sub-Application
  • Handler
  • Endpoint
  • Service
    • Routes
    • Endpoints
    • Help & Validation
    • Barricade
    • Example
  • Page
    • Master View
    • Page View

• Preprocessors

Overview

Can be used as a Connect Middleware

This module uses:

• Atma.js libs
• atma-logger
• atma-io
• appcfg

To setup a bootstrap project use Atma.Toolkit - $ atma gen server

HttpApplication

var atma = require('atma-server');
atma
	.server
	.Application({
		base:__dirname,
		configs: '/server/config/**.yml'
	})
	.done(function(app){
		// configuration and resources are loaded
		app
			.processor({
				// pipeline is executed on every request
				before: [
					function(req, res, next){ next() },
				]
				// this pipeline is executed only if the application finds any endpoint
				// (server, handler, page, subapp)
				middleware: [
					// refer to connectjs middleware documentation
					function(req, res, next){ next() },
					require('body-parser').json(),
				],
				// otherwise, if response was not completed by any middleware or any endpoint before
				// continue with this middleware pipeline.
				after: [
					function(req, res, next){ next() },
					atma.server.middleware.static
				]
			})

			// start server, portnumber is taken from the configuration
			.listen();

		// or start the server manually:
		var server = require('http')
			.createServer(app.process)
			.listen(app.config.$get('port'));

		if (app.config.debug)
			app.autoreload(server);
	});

Configuration

appcfg module is used to load the configurations and the routings. Default path is the /server/config/**.yml.

The default configuration can be viewed here - link

Resources

scripts / styles for the NodeJS application itself and for the web pages. They are defined in:

• config.env.both.scripts<Object|Array>

  config/env/both.yml - shared resources

• config.env.server.scripts<Object|Array>

  config/env/server.yml - resources for the nodejs application, e.g. server side components paths.

• config.env.client.scripts<Object|Array>, config.env.client.styles<Object|Array>

  config/env/client.yml - resources, that should be loaded on the client.

  In the DEV Mode all client-side scripts/styles/components are served to browsers without concatenation. For the production compile resources with atma custom node_modules/atma-server/tools/compile

• Define scripts and styles for a particular page in page routing.

Routing

• subapps config/app.yml

  subapps:
  	// all `rest/*` requests are piped to the Api Application
  	// `Api.js` should export the `atma.server.Application` instance
  	'rest': '/../Api.js'

• handlers config/handlers.yml

  handler:
  	location: /server/http/handler/{0}.js
  	#< default
  handlers:
  	# route - resource that exports a HttpHandler
  	'/foo': 'baz'
  		# path is '/server/http/handler/baz.js'
  		# method is '*'
  
  	'$post /qux': 'qux/postHandler'
  		# path is '/server/http/handler/quz/postHander.js'
  		# method is 'POST'

• services config/services.yml

  service:
  	location: /server/http/service/{0}.js
  	#< default
  services:
  	# route - resource that exports a HttpService @see HttpService
  	'/user': 'User'
  		# path is '/server/http/service/User.js'
  		# method is '*'
  		# futher routing is handled by the service, like '/user/:id'

• pages config/pages.yml

  page:
  	# see default config to see the default page paths
  
  pages:
  	# route - Page Definition
  
  	/:
  		id: index #optional, or is generated from the route
  
  		template: quz #optional, or is equal to `id`
  			# path is `/server/http/page/quz/quz.mask
  		master: simple #optional, or is `default`
  			# path is `/server/http/master/simple.mask`
  
  		# optional
  		secure:
  			# optional, default - any logged in user
  			role: 'admin'
  
  		scripts:
  			# scripts for the page
  		styles:
  			# styles for the page
  
  		# any other data, which then is accessable via javascript or mask
  		# `ctx.page.data.title`
  		title: String
  
  		# rewrite the page request to some other route
  		rewrite: String
  
  		# redirect the page request to some other route
  		redirect: String

Endpoints

There are 4 types of endpoints in route lookup order

• Sub Application
• Handler (generic handler)
• HttpService/Endpoint (RESTful service)
• HttpPage

Sub Application

We support application nesting, that means you can bind another server application instance for the route e.g. /api/ and all /api/** requests are piped to the app. Each application instance has its own settings and configurations. This allows to create highly modular and composit web-applications.

Handler

To declare a Handler is as simple as to define a Class/Constructor with Deferred(Promise) Interface and process function in prototypes, like this

// server/http/handler/hello.js
module.exports = Class({
	Base: Class.Deferred,
	process: function(req, res){
		this.resolve(
			data String | Object | Buffer,
			?statusCode Number,
			?mimeType String,
			?headers Object
		);
		this.reject(error)
	}
});

To bind for a route(server/config/handlers.yml):

handler:
	location: '/server/http/handler/{0}.js'
	# <- default
handlers:
	'/say/hello': Hello
	'(\.less(\.map)?$)': LessHandler
	'(\.es6(\.map)?$)': TraceurHandler

Usually, this are the low level handlers, like 'less' preprocessor. But the interface (Deferred + process(req, res)) is same also for HttpService and HttpPage

HttpEndpoint

Class and decorators oriented HttpService

import { HttpEndpoint, deco } from 'atma-server'

@deco.route('/foo')
@deco.isAuthorized()
export default class MyEndpoint extends HttpEndpoint {

    @deco.isInRole('admin')
    async '$get /:id' (
        @deco.fromUri('id', Number) id: number
    ) {
        return service.fetch(id)
    }
}

Decorators can be applied to the class or methods

• HttpEndpoint.isAuthorized()
• HttpEndpoint.isInRole(...roles: string[])
• HttpEndpoint.hasClaim(...roles: string[])
• HttpEndpoint.origin(origin: string = "*")
• HttpEndpoint.middleware(fn: (req, res?, params?) => Promise<any> | any | void)
• HttpEndpoint.createDecorator(methods: ICreateDecorator)
• HttpEndpoint.fromUri(name, Type?)
• HttpEndpoint.fromBody(Type)

Decorators are also accessable via deco export, e.g.: deco.isAuthorized()

interface ICreateDecorator {
    forCtor (Ctor: Function, meta: IHttpEndpointMeta): Function | void;
    forMethod (Proto: any, method: IHttpEndpointMethod): IHttpEndpointMethod | void
}

HttpService

Service routes

For the route docs refer to RutaJS

Sample:

module.exports = atma.server.HttpService({
	'$get /': Function | Endpoint
	'$post /': ...
	'$get /:name(foo|bar|qux)': ...
	'$put /user': ...
})

Service endpoints

Function

atma.server.HttpService(/*endpoints*/ {
	// route:handler
	'route': function(req, res, params){
		this.resolve(/*@see Handler*/);
		this.reject(...);
	},

	'route': {
		process: function(){ ... }
	}
})

Meta - help & validation

• help - list all endpoints of a service with there meta information. http://127.0.0.1/rest/user?help
• validation - when sending data with post/put, httpservice will validate it before processing

  atma.server.HttpService({
  	'/route': {
  		meta: {
  			description: 'Lorem...',
  
  			/* For request validating and the documentation */
  			arguments: {
  				// required, not empty string
  				foo: 'string',
  				// required, validate with regexp
  				age: /^\d+$/,
  
  				// optional, of type 'number'
  				'?baz': 'number',
  
  				// unexpect
  				'-quz': null,
  
  				// validate subobject
  				jokers: {
  					left: 'number',
  					right: 'number'
  				},
  
  				// validate arrays
  				collection: [ {_id: 'string', username: 'string'} ]
  			},
  			// allow only properties which are listed in `arguments` object
  			strict: false,
  
  			/* Documentation purpose only*/
  			response: {
  				baz: 'string',
  				...
  			}
  		},
  		process: function(req, res, params) { ... }
  	}
  })

  • Headers Set default headers for the service

  atma.server.HttpService({
  	'/route': {
  		meta: {
  			headers: {
  				'Access-Control-Allow-Origin': '*',
  				'Access-Control-Allow-Headers': 'Origin, X-Requested-With, Content-Type, Accept'
  			}
  		},
  		process: function(req, res, params) { ... }
  	}
  });

Barricades (Middlewares)

atma.server.HttpService({
	// route - Barricade (Middleware pattern)
	'/route': [
		function(req, res, params, next){
			// error example
			if (req.body.name == null){
				next('Name argument expected');
				return;
			}

			// continue
			req.name = req.body.name;
			next();

			// stop processing
			this.resolve(...);
			this.reject(...);
		},
		function(req, res, params, next){
			...
		},
		...
	],

	// same with `help`
	'/other/route': {
		meta: { ... }
		process: [
			fooFunction,
			bazFunction,
			...
		]
	}
})

Service and the application routing example

// server/http/service/time.js
module.exports = atma.server.HttpService({
	'/': function(req, res){
		this.resolve('This is a time service');
	},
	'/:transport(console|file|client)': function(req, res, params){
		var time = new Date().toString(),
			that = this;
		switch(params.transport){
			case 'console':
				console.log(' > time', time);
				this.resolve('Pushed to console');
				return;
			case 'file':
				io
					.File
					.writeAsync('someFile.txt')
					.pipe(this, 'fail')
					.done(() => {
						this.resolve('Saved to file');
					});
				return;
			case 'client':
				this.resolve(time);
				return;
		}
	}
})

# server/config/services.yml

service:
	location: /server/http/service/{0}.js'
	# <- default

services:
	'/time': time

HttpPage

HttpPage consists of 3 parts

• Controller
• Master View Template
• View Template

You would rare redefine the default controller, as each Page should consist of a component composition, so that the logic could be moved to each component. We wont explain what a component is, as you should refer to MaskJS and MaskJS.Node Some things we remind:

• Context

  { req: <Request>, res: <Response>, page: <HttpPage (current instance)> }

• Render-mode

  mode: 'server' | 'client' | 'both' // @default is 'both'
  modeModel: 'server' // if `server` is defined, the model wont be serialized

• Cache Each components output could be cached and the conditions could be defined.

  • byProperty: For each unique value from model or ct

Example

mask.registerHandler(':requestedUrl', Compo({
	mode: 'server:all'
	modelMode: 'server:all'
	cache: {
		byProperty: 'ctx.req.url'
	},

	onRenderStart: function(model, ctx){
		this.nodes = jmask('h4').text(ctx.req.url);
	}
}))

Going back to the HttpPage, lets start from a master view template

Master View

Refer to the layout component

Example:

// server/http/master/default.mask
layout:master #default {
	:document {

		head {
			meta http-equiv="Content-Type" content="text/html;charset=utf-8";
			meta name="viewport" content="maximum-scale=1.5, minimum-scale=.8, initial-scale=1, user-scalable=1";
			title > "Atma.js"

			atma:styles;
		}
		body {

			@placeholder #body;

			atma:scripts;
		}
	}
}

Page View

// server/http/page/hello.mask
layout:view master=default {
	@content #body {
		'Hello World'
	}
}

The routing is also made via the configuration files

# server/config/pages.yml

pages:
	'/hello':
		id: hello

Preprocessors

E.g., to use ES6 or Less files, please install server plugins

• TraceurCompiler
• Less

# atma.toolkit, is only a helper util to intall plugins (further on is not required)
$ npm i atma -g
$ atma plugin install atma-loader-traceur
$ atma plugin install atma-loader-less

:copyright: 2014-2015; MIT; The Atma.js Project