defmodule Phoenix.CodeReloader do
@moduledoc """
A plug and module to handle automatic code reloading.
For each request, Phoenix checks if any of the modules previously
compiled requires recompilation via `__phoenix_recompile__?/0` and then
calls `mix compile` for sources exclusive to the `web` directory.
To avoid race conditions, all code reloads are funneled through a
sequential call operation.
"""
## Server delegation
@doc """
Reloads code within the paths specified in the `:reloadable_paths`
config for the endpoint.
This is configured in your application environment like:
config :your_app, YourApp.Endpoint,
reloadable_paths: ["web"]
Keep in mind that the paths passed to :reloadable_paths must be
a subset of the paths specified in the :elixirc_paths option of
`project/0` in mix.exs.
"""
@spec reload!(module) :: :ok | :noop | {:error, binary()}
defdelegate reload!(endpoint), to: Phoenix.CodeReloader.Server
## Plug
@behaviour Plug
import Plug.Conn
@doc """
API used by Plug to start the code reloader.
"""
def init(opts), do: Keyword.put_new(opts, :reloader, &Phoenix.CodeReloader.reload!/1)
@doc """
API used by Plug to invoke the code reloader on every request.
"""
def call(conn, opts) do
case opts[:reloader].(conn.private.phoenix_endpoint) do
{:error, output} ->
conn
|> put_resp_content_type("text/html")
|> send_resp(500, template(conn, output))
|> halt()
_ ->
conn
end
end
defp template(conn, output) do
"""
CompilationError at #{method(conn)} #{conn.request_path}
CompilationError at #{method(conn)} #{conn.request_path}
Showing console output
"""
end
defp method(%Plug.Conn{method: method}), do: method
end