git.r.bdr.sh - rbdr/dasein/blob - lib/dasein.js

   1 'use strict';
   2
   3 const Koa = require('koa');
   4 const KoaBodyParser = require('koa-bodyparser');
   5 const KoaJwt = require('koa-jwt');
   6 const KoaRoute = require('koa-route');
   7 const KoaSend = require('koa-send');
   8 const KoaStatic = require('koa-static');
   9 const Path = require('path');
  10
  11 const AuthHandler = require('./handlers/auth');
  12 const PostsHandler = require('./handlers/posts');
  13
  14 const internals = {};
  15
  16 internals.k401Location = '/401.html';
  17 internals.kMainLocation = '/';
  18
  19 /**
  20  * The Dasein class is the main entry point for the application.
  21  *
  22  * @class Dasein
  23  * @param {Dasein.tConfiguration} config the initialization options to
  24  * extend the instance
  25  */
  26 module.exports = internals.Dasein = class Dasein {
  27
  28   constructor(config) {
  29
  30     Object.assign(this, config);
  31   }
  32
  33   /**
  34    * Initializes the application and starts listening. Also prints a
  35    * nice robotic banner with information.
  36    *
  37    * @function run
  38    * @memberof Dasein
  39    * @instance
  40    */
  41   run() {
  42
  43     this._initializeServer();
  44     this._startServer();
  45     this._printBanner();
  46
  47     return Promise.resolve();
  48   }
  49
  50   // Initializes the Koa application and all the handlers.
  51
  52   _initializeServer() {
  53
  54     const self = this;
  55
  56     this._app = Koa();
  57
  58     this._app.use(KoaStatic(this.staticDirectory));
  59     this._app.use(KoaBodyParser());
  60
  61     // Error handler
  62
  63     this._app.use(function * (next) {
  64
  65       try {
  66         yield next;
  67       }
  68       catch (err) {
  69         this.status = err.status || 500;
  70
  71         const response = {
  72           error: err.message,
  73           status: this.status
  74         };
  75
  76         if (response.status === 401) {
  77           response.error === 'Protected resource, use Authorization header to get access';
  78         }
  79
  80         this.body = response;
  81
  82         this.app.emit('error', err, this);
  83       }
  84     });
  85
  86     this._app.use(KoaJwt({
  87       secret: this.jwt.secret,
  88       passthrough: true
  89     }));
  90
  91     this._initializeAuthRoutes();
  92     this._initializePostsRoutes();
  93
  94     this._app.use(function * () {
  95
  96       yield KoaSend(this, Path.join(self.staticDirectory, 'index.html'));
  97     });
  98
  99   }
 100
 101   // Initialize routes for auth
 102
 103   _initializeAuthRoutes() {
 104
 105     const authHandler = new AuthHandler({
 106       jwt: this.jwt,
 107       twitter: this.twitter
 108     });
 109     this._app.use(KoaRoute.get('/api/auth/login', authHandler.login()));
 110     this._app.use(KoaRoute.post('/api/auth/callback', authHandler.callback()));
 111   }
 112
 113   // Initialize routes for posts
 114
 115   _initializePostsRoutes() {
 116
 117     const postsHandler = new PostsHandler({
 118       ttl: this.ttl,
 119       redis: this.redis
 120     });
 121     this._app.use(KoaRoute.get('/api/posts', postsHandler.findAll()));
 122     this._app.use(KoaRoute.get('/api/posts/:id', postsHandler.find()));
 123     this._app.use(KoaRoute.post('/api/posts', postsHandler.create()));
 124     this._app.use(KoaRoute.delete('/api/posts/:id', postsHandler.delete()));
 125
 126   }
 127
 128   // Starts listening
 129
 130   _startServer() {
 131
 132     this._app.listen(this.port);
 133   }
 134
 135   // Prints the banner.
 136
 137   _printBanner() {
 138
 139     console.log('        .');
 140     console.log('       /');
 141     console.log('    +-----+');
 142     console.log(`    | o o |  - Listening Gladly, Try me on port: ${this.port}`);
 143     console.log('    +-----+');
 144     console.log('  +---------+');
 145     console.log(' /|    [][] |\\');
 146     console.log(' ||         | |');
 147     console.log(' ||         |  \\c');
 148     console.log(' ^+---------+');
 149     console.log('      (.) ');
 150   }
 151 };