# Mppm

## Dependencies

We may recommend using [asdf](https://github.com/asdf-vm/asdf) to install
dependencies. It allows you to install and manage various versions of most common
runtimes, as well as to pinpoint specific version of it for any paths.

### System
  As of now, the application is strictly developed on CentOS 7. However it should
  work on any Linux distribution.

  - inotify-tools
  - PostgreSQL 10
  - NodeJS 6.4

### Erlang/Elixir

  - Erlang/OTP 22
  - Elixir 1.9.4


## Prerequisites

  - [Trackmania OAuth API registration](https://api.trackmania.com/manager)


## Config

  After copying the \*.exs.dist files into \*.dist, make the following changes:

### config.exs
  - secret_key_base: ""
  (generate generate your own key with `mix phx.gen.secret`)
  - signing_salt: ""
  ( generate your own salt with `mix phx.gen.secret 32`)

### (dev|prod).exs

  - url: [host: "example.com", port: 80]
  - redirect_uri: "your_registered_callback_uri_for_Trackmania_OAuth"

### (dev|prod).secret.exs

  - Set your PostgreSQL hostname,  username, password and edit the  database name
  if you wish
  - Set your client_id and client_secret for the Trackmania OAuth


Once everything is installed, you're good to start MPPM:

  * Go to the application root folder
  * Install elixir dependencies with `mix deps.get` (you may also `mix deps.compile`
    but that will be done anyway at start)
  * Create and migrate your database with `mix ecto.setup`
  * Install Node.js dependencies with `npm install --prefix assets/`
  * Start Phoenix endpoint with `mix phx.server`

Now you can visit [`localhost:4000`](http://localhost:4000) from your browser.

Ready to run in production? Please [check our deployment guides](https://hexdocs.pm/phoenix/deployment.html).

## Elixir / Phoenix resources

  * Elixir doc: https://hexdocs.pm/elixir/Kernel.html
  * Phoenix: https://hexdocs.pm/phoenix
  * Phoenix PubSub: https://hexdocs.pm/phoenix_pubsub
  * Phoenix LiveView: https://hexdocs.pm/phoenix_live_view
  * Source: https://github.com/phoenixframework/phoenix

## Game server message broker

A broker is made up of one supervisor (Mppm.Broker.Supervisor) and two GenServers:
- Mppm.Broker.ReceiverServer
- Mppm.Broker.RequesterServer

The Supervisor is started after game server launch, once it opened its ports. The
ReceiverServer then opens the connection and provides a call method so that the
RequesterServer can retrieve the open port. Everything's stopped on server shutdown.

This design choice hase been made to allow either the receiving or requesting part
of the broker to be able to independently fail without impeding its counterpart.



## PubSub Topics

\* > server login

### "players-status"

- {:user_connection_to_server, server_login, user_login, is_spectator?}
- {:servers_users_updated, server_login, servers_users}
- {:role_rmoved, , role}
- {:role_granted, , role}

### "maps-status"

- {:loaded_map, server_login, map_uid}
- {:update_server_map, server_login, track_uid}
- {:endmap, server_login, track_uid}
- {:current_track_info, server_login, track_uid}


### "race-status"

- {:player_waypoint, server_login, user_login, waypoint_nb, time}
- {:turn_start, server_login}


### "server-status:*"

- {:new_chat_message, chat_message}
- {:beginmatch}
- {:endmatch}
- {:beginmap, track_info_map}
- {:endmap}
- {:start_of_match, server_login}
- {:score, server_login}
- {:end_of_game, server_login}
- {:loaded_map, server_login, map_uid}
- {:podium_start, server_login}
- {:podium_end, server_login}
- {:broker_started, state.login}


### "broker-status:*"

- {:connection_established, socket}


### "ruleset-status"

- {:ruleset_change, server_login, ruleset}