installation_rails.md

Install for Rails like projects

With the Webpacker Gem

Within the projects root directory execute:

owl-install webpacker

It configures all the required things and merges a basic configuration to config/webpack/environment.js. Adjust that file to your preference. Opal ruby files should then go in the newly created app/opal directory. With the option -o the directory can be named differently, for example:

owl-install rails -o hyperhyper

A directory app/hyperhyper will be created, opal files should then go there and will be properly resolved by webpack.

The entry file for imports is app/javascript/packs/application.js.

The OpalWebpackLoader::RailsViewHelper is not needed.

Continue below, section "For Both".

Without the Webpacker Gem

If you start a new rails project, the following options are recommended for rails new: --skip-sprockets --skip-javascript

Then within the projects root directory execute:

owl-install rails

Opal ruby files should then go in the newly created app/opal directory. With the option -o the directory can be named differently, for example:

owl-install rails -o hyperhyper

A directory app/hyperhyper will be created, opal files should then go there and will be properly resolved by webpack.

Complete set of directories and files created by the installer for projects with a rails like structure:

project_root
    +- app
        +- assets
            +- javascripts  # javascript entries directory
                +- application.js
                +- application_common.js
                +- application_ssr.js
                +- application_webworker.js
            +- styles       # directory for stylesheets
        +- opal             # directory for opal application files, can be changed with -o
    +- config
        +- webpack          # directory for webpack configuration files
            +- debug.js
            +- development.js
            +- production.js
        +- initializers
            +- opal_webpack_loader.rb  # initializer for owl
    +- package.json         # package config for npm/yarn and their scripts
    +- public
        +- assets           # directory for compiled output files
    +- Procfile             # config file for foreman

To load the compiled asset files the owl_include_tag view helper must be used. Please see the sections "View Helper" and "Project configuration options for the view helper" in the main README.

Continue below, section "For Both".

For Both

Please see the messages of owl-install. You may need to manually add the following gems to the projects Gemfile:

gem 'opal', github: 'janbiedermann/opal', branch: 'es6_modules_1_2' # use the recommend branch of the main README
gem 'opal-webpack-loader', '~> 0.13.0' # use the most recent released version here

Then:

yarn install
bundle install