Phoenix.CodeReloader (Phoenix v1.5.5) View Source

A plug and module to handle automatic code reloading.

For each request, Phoenix goes through all modules and checks if any of them implement a __phoenix_recompile__?/0 function. If they do and it returns true, the module source file is touched, forcing it to be recompiled. For this functionality to work, Phoenix requires you to add the :phoenix compiler to your list of compilers:

compilers: [:phoenix] ++ Mix.compilers()

This is useful, for example, to recompile modules that depend on external systems, such as directories, databases, etc. Note if you simply depend on external files, @external_resource annotation should be used.

To avoid race conditions, all code reloads are funneled through a sequential call operation.

Link to this section Summary

Functions

call(conn, opts)

API used by Plug to invoke the code reloader on every request.

init(opts)

API used by Plug to start the code reloader.

reload!(endpoint)

Reloads code for the current Mix project by invoking the :reloadable_compilers on the list of :reloadable_apps.

Link to this section Functions

call(conn, opts)

API used by Plug to invoke the code reloader on every request.

init(opts)

API used by Plug to start the code reloader.

reload!(endpoint)

Specs

reload!(module()) :: :ok | {:error, binary()}

Reloads code for the current Mix project by invoking the :reloadable_compilers on the list of :reloadable_apps.

This is configured in your application environment like:

config :your_app, YourApp.Endpoint,
  reloadable_compilers: [:gettext, :phoenix, :elixir],
  reloadable_apps: [:ui, :backend]

Keep in mind :reloadable_compilers must be a subset of the :compilers specified in project/0 in your mix.exs.

The :reloadable_apps defaults to nil. In such case default behaviour is to reload current project if it consists of single app, or all applications within umbrella project. You can set :reloadable_apps to subset of default applications to reload only some of them, empty list - to effectively disable code reloader, or include external applications from library dependencies.