reload.mk

A live reload plugin for erlang.mk.

Usage

First, add reload.mk as a plugin and a build dependency:

PROJECT = myproject
BUILD_DEPS = reload_mk
DEP_PLUGINS = reload_mk

include erlang.mk

Then in one terminal: make run RELOADABLE=1. Keep it running.

Now you can modify any source files in your project and run make reload:

% make reload
 DEPEND myproject.d
 ERLC   myproject.erl myproject_app.erl
 APP    myproject
 RELOAD myproject

=INFO REPORT==== 3-Oct-2015::15:05:18 ===
    reload_mk: "Reloaded"
    module: myproject
    path: "/home/bullno1/Projects/myproject/_rel/myproject_release/lib/myproject-rolling/ebin/myproject.beam"
** at node myproject@127.0.0.1 **
ok

To avoid having to type make reload all the time, use make auto-reload. You need to have inotify-tools installed for this command to work.

An example project can be found at https://github.com/bullno1/reload.mk-example.

Running code on reload

It is possible to have a function called whenever a module is reloaded. This is useful for things like reloading cowboy's route. To do so, just use the on_reload attribute:

-module(my_http_listener).
-export([reload_routes/0]). % Reload function must be exported
-on_reload(reload_routes/0).

reload_routes() ->
	cowboy:set_env(my_http_listener, dispatch, cowboy_router:compile(dispatch())).

dispatch() ->
	[
	% Routes
	].

Now, every time my_http_listener is modified, it will automatically calls reload_routes.

Configuration

RELOAD_MK_WATCH_DIRS can be set to a list of directories that make auto-reload needs to watch. For example, if you are using erlydtl templates, put the following in your Makefile:

RELOAD_MK_WATCH_DIRS = src templates

By default, it is set to src deps.