Ruby

Build with Flox

Not only can you develop your software with Flox, but you can build it as well. See the builds concept page for more details.

Since Ruby is not a compiled language, to create an executable artifact you must create a shell script that calls bundle exec. Configure bundler to use the local directory to store the bundles by setting $GEM_HOME to something like ./vendor. If you're Gemfile compiles native extensions, you may also want to unset CPATH. See the Flox ruby environment for more information, examples and specific details.

For example, say you have an application whose source is in app.rb, and that you created a script called myproject at the root of your repository with the following contents:

#!/usr/bin/env bash

bundle exec ruby app.rb

The build command for your application would look like this:

[build.myproject]
command = '''
  # Vendor dependencies
  bundle

  # Create the output directories
  mkdir -p $out/{lib,bin}

  # Copy source files to $out/lib
  cp -pr * $out/lib

  # Move the executable script
  mv $out/lib/myproject $out/bin/myproject
'''

Vendoring dependencies in pure builds

As discussed in the pure builds of the Builds concept page, pure builds run in a sandbox without network access on Linux. A pure build can be run as a multi-stage build where the first step vendors dependencies. An example is shown below:

[build.myproject-deps]
command = """
   # Don't use or update paths in the real project config.
   export BUNDLE_IGNORE_CONFIG=true

   # Pre-fetch the deps outside of the sandbox.
   export BUNDLE_PATH=$out
   export BUNDLE_CACHE_PATH=${out}/cache
   bundle cache --no-install

   # These gems appear to be duplicated irrespective of `--no-install`
   rm -rf $out/ruby
"""

[build.myproject]
command = """
   mkdir -p $out/{lib,bin}

   # Don't use or update paths in the real project config.
   export BUNDLE_IGNORE_CONFIG=true

   # Perform an isolated install using pre-fetched deps.
   export BUNDLE_PATH=$out/lib/vendor
   export BUNDLE_CACHE_PATH=${myproject-deps}/cache
   export BUNDLE_DEPLOYMENT=true
   bundle install --standalone --local

   cp Gemfile Gemfile.lock $out/lib
   cp app.rb quotes.json $out/lib
   cp quotes $out/bin/myproject
"""
sandbox = "pure"