This is an example project, demonstrating extensive build customisation based on a combination of rebar plugins and some custom tools.

Run it like so.

$ sh build.sh

The goals of this (example) project are to determine the best (likely) simple approaches to

• being able to build required dependencies that are not rebar compatible
  • because they are not packaged according to OTP principles
  • because they are packaged in a way that rebar cannot handle
  • because they rely on foreign tools (such as make)
  • because they are not Erlang code (gasp), e.g., Java node(s)
• not depending on autotools/make to preprocess a build for a target environment
• bootstrapping rebar on the target system
  • instead of assuming an embedded binary will fit in any environment
  • allowing for custom forks/branches of rebar
• [*]bootstrapping rebar plugins so that multiple passes are not required to build
• [*]bootstrapping configure with minimal code duplication across projects
• [*]handling multi-phase and/or multi-profile builds
  • e.g., see the differences between rebar.config and release.config

Items marked with an [*]asterisk are still in progress, and most of the features of this sample are in some way experimental, although I am actively using all of them in a few other (ongoing) open source projects.

This is all very experimental, and I'm treating it as an incubator for various rebar plugins, customisations and other things (including a very lightweight bootstrap/configure tool chain for Erlang/OTP projects).

If you want to know how it works, dig in to build.sh and then follow the yellow brick road, taking note of your stops at

• the ./bootstrap script, which hocks together a special build project
  • I'm going to make this invisible in a future release of the tool(s)
• the pre_release_plugin, which is used at various stages of the build
• the libconf definitions provided by configure.erl
  • In future releases, you'll be able to do this with configuration or code
• the rebar.config used to install the plugins and deps
• the rebar_alien_plugin and rebar_alt_deps plugins (https://github.com/hyperthunk)
• the release.config that is used to build the release (using rebar)

A number of the tools that this project uses are under development and likely to see some churn (as of 4th November 2011), so copying the approach taken here verbatim is probably not a very sustainable (or sensible) thing to do.

In particular, you should look at the roadmap for the following projects, to get and understanding of how changes to them will affect a build of this type (and complexity)

• rebar_alt_deps
• rebar_alien_plugin
• remote_plugin_loader
• libconf
• libconf-bootstrap