DKX/Http/Server

Super simple HTTP server with middlewares support for node.js.

Installation

$ npm install --save @dkx/http-server

or with yarn

$ yarn add @dkx/http-server

Basic usage

const {Server} = require('@dkx/http-server');
const {someRandomMiddleware} = require('some-random-middleware');

const app = new Server;

app.use(someRandomMiddleware);

app.run(8080, () => {
    console.log('Server is running on port 8080');
});

Writing middlewares

Each middleware is just an ordinary async function.

Middleware must call the next function with current response.

const {Server} = require('@dkx/http-server');

async function appendHeaderMiddleware(request, response, next)
{
    response = response.withHeader('X-My-custom-header', 'hello world');
    return next(response);
}

const app = new Server;

app.use(appendHeaderMiddleware);

Writing response data

function writeResponseDataMiddleware(request, response, next)
{
    response.write('hello');
    response.write(' ');
    response.write('world');
    
    return next(response);
}

Passing data between middlewares

function middlewareA(request, response, next, state)
{
    state.message = 'hello world';
    return next(response);
}

function middlewareB(request, response, next, state)
{
    console.log(state.message);    // output: hello world
    return next(response);
}

Testing middlewares

Testing new middlewares is really easy with the built in helper function. It construct all the necessary objects and runs the middleware for you.

const {testMiddleware} = require('@dkx/http-server');

function myUselessMiddleware(request, response, next)
{
	response.write('hello world');
    response = response.withHeader('X-Middleware-header', 'lorem ipsum');
    return next(response);
}

const data = [];
const response = await testMiddleware(myUselessMiddleware, {
    method: 'POST',
    url: '/v1/users/5',
    body: 'some HTTP body',
    headers: {
        'X-My-custom-http-header': 'hello world'
    },
    state: {
        msg: 'My custom shared state'
    },
    onBodyWrite: function(chunk) {
    	data.push(chunk.toString());
    },
    next: async function(res) {
    	console.log('Custom next function called');
    	return res;
    },
});

console.log(response.getHeader('X-Middleware-header'));  // output: "lorem ipsum"
console.log(data);  // output: ["hello world"]

The testMiddleware function can be used just with your middleware:

testMiddleware(myUselessMiddleware);

Server object

• use

  Append middleware.

  Arguments:

  middleware: Middleware: middleware to attach.

• run()

  Start the HTTP server.

  Arguments:

  port: number: port where the HTTP server will be listening for new requests. fn: () => void: callback called when server is ready to handle requests.

• close()

  Stop running HTTP server.

  Arguments:

  fn: () => void: callback called when server is completely shut down.

• middleware()

  Run custom Request and Response.

  Arguments:

  request: Request: Custom Request object response: Response: Custom Response object

  Return:

  Promise<Response>: New response after running through the middleware stack.

Request object

• method

  Contains request method (GET, POST, ...).

• url

  Contains requested URL.

• headers

  Contains request HTTP headers.

• body

  Readable stream for accessing request data.

• hasHeader()

  Test if header exists.

  Arguments:

  name: string: Name of header.

  Return:

  boolean

• getHeader()

  Return HTTP header.

  Arguments:

  name: string: Name of header.

  Return:

  string|Array<string>|undefined

Response object

The Response is an immutable object.

• statusCode

  Response status code, default 200.

• statusMessage

  Response status message, default is an empty string.

• headers

  Contains list of currently returned HTTP headers.

• write()

  Method for writing data into response body.

  Arguments:

  chunk: any: data to write.

• withStatus()

  Write response status.

  Arguments:

  code: number: new response status code. message: string: new response status message, default is an empty string.

  Return:

  Response: cloned Response object with modified status.

• hasHeader()

  Check whether header exists.

  Arguments:

  name: string: name of HTTP header to check.

  Return:

  boolean

• getHeader()

  Get HTTP response header.

  Arguments:

  name: string: name of HTTP header. defaultValue: undefined|string|number|Array<string>: default value to return if HTTP header does not exists.

  Return:

  undefined|string|number|Array<string>

• withHeader()

  Write response header.

  Arguments:

  name: string: name of the new header. value: string: value of the new header.

  Return:

  Response: cloned Response object with modified headers.

• withVaryHeader()

  Write vary HTTP response header.

  Arguments:

  field: string|Array<string>: name of header you wish to add into vary header

  Return:

  Response: cloned Response object with modified headers.

• removeHeader()

  Remove response header.

  Arguments:

  name: string: name of the removed header.

  Return:

  Response: cloned Response object with modified headers.

ResponseBody object

Writable stream for writing the response data.

• write()

  Write response chunk

  Arguments:

  chunk: chunk of data to write.