# PhoenixReverseProxy

**Share a port between many Phoenix apps in an umbrella or multiple endpoints in a single app**

## Setup
This library offers all the essentials for directing requests and websockets
from a single proxy application to your umbrella (or a standard Elixir app
with various endpoints). It enables you to run multiple Phoenix applications
within the same umbrella using the same port or have multiple endpoints
within a single app.

Start by creating a Phoenix application in your umbrella `apps` folder:
  ```bash
  (cd apps && mix phx.new --no-webpack --no-ecto --no-html --no-gettext --no-dashboard reverse_proxy)
  # Optionally you can delete unused files
  rm -rf apps/reverse_proxy/lib/reverse_proxy_web/{channels,controllers,views}
  ```

If [available in Hex](https://hex.pm/docs/publish), the package can be installed
by adding `phoenix_reverse_proxy` to your list of dependencies in `mix.exs`:

```elixir
def deps do
  [
    {:phoenix_reverse_proxy, "~> 1.0.0"}
  ]
end
```

In `apps/reverse_proxy/lib/reverse_proxy_web/endpoint.ex` replace the contents with
this and replace the default endpoint and add appropriate endpoints:
  ```elixir
  defmodule ReverseProxyWeb.Endpoint do
    use PhoenixReverseProxy, otp_app: :reverse_proxy

    # IMPORTANT: All of these macros except for proxy_default/1
    #            can take a path prefix so they all have an arity
    #            of 2 and 3.

    # Maps to http(s)://api.example.com/v1
    proxy("api.example.com", "v1", ExampleApiV1.Endpoint)

    # Maps to http(s)://api.example.com/v2
    proxy("api.example.com", "v2", ExampleApiV2.Endpoint)

    # Matches the domain only and no subdomains
    proxy("example.com", ExampleWeb.Endpoint)
    # Matched any subdomain such as http(s)://images.example.com/
    # but not the domain itself http(s)://example.com/
    proxy_subdomains("example.com", ExampleSubs.Endpoint)

    # Matches all subdomains and the domain itself.
    # This is equivalent to combining these rules:
    #   proxy("foofoovalve.com", FoofooValve.Endpoint)
    #   proxy_subdomains("foofoovalve.com", FoofooValve.Endpoint)
    proxy_all("foofoovalve.com", FoofooValve.Endpoint)

    # Matches anything not matched above
    proxy_default(ExampleWeb.Endpoint)
  end
  ```

In your config you must disable your other Phoenix applications from
listening on TCP ports. In your current endpoint configuration make the
following modifications.

  ```elixir
  # Configures the endpoint
  config :example_web, ExampleWeb.Endpoint,
    # Add this
    server: false,
    # Remove this and add it to the proxy endpoint configuration
    http: [port: System.get_env("PHX_PORT") || 4000],
    ...
  ```

Move contents of the files `apps/reverse_proxy/config/*.exs` to the
corresponding `config/*.exs` config files.

Documentation can be generated with [ExDoc](https://github.com/elixir-lang/ex_doc)
and published on [HexDocs](https://hexdocs.pm). Once published, the docs can
be found at [https://hexdocs.pm/phoenix_reverse_proxy](https://hexdocs.pm/phoenix_reverse_proxy).