support/doc/development/server/code.md

   1 # Server code documentation
   2
   3 The server is a web server developed with [TypeScript](https://www.typescriptlang.org/)/[Express](http://expressjs.com).
   4
   5
   6 ## Technologies
   7
   8   * [TypeScript](https://www.typescriptlang.org/) -> Language
   9   * [PostgreSQL](https://www.postgresql.org/) -> Database
  10   * [Express](http://expressjs.com) -> Web server framework
  11   * [Sequelize](http://docs.sequelizejs.com/en/v3/) -> SQL ORM
  12   * [WebTorrent](https://webtorrent.io/) -> BitTorrent tracker and torrent creation
  13   * [Mocha](https://mochajs.org/) -> Test framework
  14
  15
  16 ## Files
  17
  18 The server main file is [server.ts](/server.ts).
  19 The server modules description are in the [package.json](/package.json) at the project root.
  20 All other server files are in the [server](/server) directory:
  21
  22     server.ts -> app initialization, main routes configuration (static routes...)
  23     config    -> server YAML configurations (for tests, production...)
  24     scripts   -> Scripts files for npm run
  25     server
  26     |__ controllers  -> API routes/controllers files
  27     |__ helpers      -> functions used by different part of the project (logger, utils...)
  28     |__ initializers -> functions used at the server startup (installer, database, constants...)
  29     |__ lib          -> library function (WebTorrent, OAuth2, ActivityPub...)
  30     |__ middlewares  -> middlewares for controllers (requests validators, requests pagination...)
  31     |__ models       -> Sequelize models for each SQL tables (videos, users, accounts...)
  32     |__ tests        -> API tests and real world simulations (to test the decentralized feature...)
  33
  34
  35 ## Conventions
  36
  37 Uses [JavaScript Standard Style](http://standardjs.com/).
  38
  39 ## Architecture
  40
  41 The server is composed by:
  42
  43   * a REST API (Express framework)
  44   * a WebTorrent Tracker
  45
  46 A video is seeded by the server with the [WebSeed](http://www.bittorrent.org/beps/bep_0019.html) protocol (HTTP).
  47
  48 ![Architecture scheme](/support/doc/development/server/upload-video.png)
  49
  50 When a user uploads a video, the rest API create the torrent file and then adds it to its database.
  51
  52 If a user wants to watch the video, the tracker will indicate all other users that are watching the video + the HTTP url for the WebSeed.
  53
  54 ## Newcomers
  55
  56 The server entrypoint is [server.ts](/server.ts). You can begin to look at this file.
  57 Then you can try to understand the [controllers](/server/controllers): they are the entrypoint of each API request.