http_proxy

defmodule HttpProxy do
  @moduledoc """
  HttpProxy is a simple http proxy.

  If you access to particular URL like `http://localhost:8080`, then the http_proxy forward the request to other URL based on configuration.

  HttpProcy support two features.

  1. HttpProxy support multiport proxy fearue.
  2. HttpProxy support play/record proxied request.

  Multiport proxy means that the proxy receives request with particular port and the proxy send request to other address. And you can set the feature against several mulatiple port.

  # Multiport proxy

  For example, you set configuratio like the followings in your project and do `mix proxy`. Then the proxy send request to "http://google.com" if anyone snds to "http://localhost:4000". And the proxy send request to "http://yahoo.com" if anyone send request to "http://localhost:4001".

  ## example
  1. Set configuration as the following in `config/config.exs`.

          use Mix.Config

          config :http_proxy,
          proxies: [
                     %{port: 4000,
                       to:   "http://google.com"},
                     %{port: 4001,
                       to:   "http://yahoo.com"}
                    ]
          record: false,
          play: true,
          export_path: "test/example",
          play_path: "test/data"

  2. Access to `http://localhost:4000` via Web Browser.
      - or access to  `http://localhost:4001`.
  3. The http_proxy forward to **http://google.com** .
      - or forward to  **http://yahoo.com**

  # Play/Record proxied request.

  If you set `record: true` in the configuration, the proxy export request into local file as JSON. You can export requests in particular path which is set as `export_path: "test/example"`. Default is "default".

  If you set `play: true` in the configuration, the proxy read mapping files and reply them when anyone accesses to the proxy via particular ports.

  Please read `test/data/mappings/*.json` if you would like to know the format of playing the reqponse.
  """

  use Application
  alias HttpProxy.Supervisor, as: HttpProxySup

  @spec start(:normal, []) :: pid
  def start(_type, _args) do
    HttpProxySup.start_link
  end

  @doc """
  Stopt http_proxy.
  """
  @spec stop :: :ok
  def stop do
    Application.stop :ranch
    Application.stop :cowlib
    Application.stop :cowboy
    Application.stop :idna
    Application.stop :mimerl
    Application.stop :certifi
    Application.stop :hackney
    Application.stop :plug
    Application.stop :http_proxy
  end

  @doc """
  Start http_proxy.
  If the proxy is already running, return `{:error, {:already_started, :http_proxy}}`
  """
  @spec start() :: :ok | {:error, tuple}
  def start do
    Application.start :ranch
    Application.start :cowlib
    Application.start :cowboy
    Application.start :idna
    Application.start :mimerl
    Application.start :certifi
    Application.start :hackney
    Application.start :plug
    Application.start :http_proxy
  end
end