gem-rebuild

gem-rebuild (plugin)

The gem rebuild command allows you to build a gem and compare it to an existing .gem file, to see if they are identical.

This command provides a base for implementing Reproducible Builds for Ruby gems.

Installation

Install the gem by executing:

$ gem install gem-rebuild

Usage

General usage is:

$ gem rebuild GEM_NAME GEM_VERSION

When gem rebuild succeeds, it prints the line SUCCESS - original and rebuild hashes matched.

However, when gem rebuild fails, it prints the line FAILURE - original and rebuild hashes did not match.

You can also specify --diff to compare the two files using diffoscope on failure.

Example success

~/test$ git clone --quiet https://github.com/duckinator/okay.git
~/test$ cd okay
~/test/okay$ git checkout v12.0.3
HEAD is now at 40fe265 Merge pull request #16 from duckinator/bump-deps
puppy@orthrus:~/test/okay$ gem rebuild okay 12.0.3
Fetching okay-12.0.3.gem
Downloaded okay version 12.0.3 as /tmp/gem_rebuild20240130-73307-ai5jxs/old/okay-12.0.3.gem.
  Successfully built RubyGem
  Name: okay
  Version: 12.0.3
  File: okay-12.0.3.gem

Built at: 2024-01-01 08:05:03 EST (1704114303)
Original build saved to:   /tmp/gem_rebuild20240130-73307-ai5jxs/old/okay-12.0.3.gem
Reproduced build saved to: /tmp/gem_rebuild20240130-73307-ai5jxs/new/okay-12.0.3.gem
Working directory: /usr/home/puppy/test/okay

Hash comparison:
  c6017966f3498623910f9a4a7bfcbd98ebab881f0e1315491b3340afa2e20b1c      /tmp/gem_rebuild20240130-73307-ai5jxs/old/okay-12.0.3.gem
  c6017966f3498623910f9a4a7bfcbd98ebab881f0e1315491b3340afa2e20b1c      /tmp/gem_rebuild20240130-73307-ai5jxs/new/okay-12.0.3.gem

SUCCESS - original and rebuild hashes matched
~/test/okay$

Example failure

~/test/okay$ echo "# some change" >> lib/okay.rb
~/test/okay$ gem rebuild okay 12.0.3
Fetching okay-12.0.3.gem
Downloaded okay version 12.0.3 as /tmp/gem_rebuild20240130-73881-x2dknj/old/okay-12.0.3.gem.
WARNING:  open-ended dependency on cacert (>= 0) is not recommended
  use a bounded requirement, such as "~> x.y"
WARNING:  See https://guides.rubygems.org/specification-reference/ for help
  Successfully built RubyGem
  Name: okay
  Version: 12.0.3
  File: okay-12.0.3.gem

Built at: 2024-01-01 08:05:03 EST (1704114303)
Original build saved to:   /tmp/gem_rebuild20240130-73881-x2dknj/old/okay-12.0.3.gem
Reproduced build saved to: /tmp/gem_rebuild20240130-73881-x2dknj/new/okay-12.0.3.gem
Working directory: /usr/home/puppy/test/okay

Hash comparison:
  c6017966f3498623910f9a4a7bfcbd98ebab881f0e1315491b3340afa2e20b1c      /tmp/gem_rebuild20240130-73881-x2dknj/old/okay-12.0.3.gem
  8910ae67d46e9cccc59c2a2dd08b29ddf03ac703bc95bcc7f69e1722926def94      /tmp/gem_rebuild20240130-73881-x2dknj/new/okay-12.0.3.gem

FAILURE - original and rebuild hashes did not match
~/test/okay$

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and the created tag, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/duckinator/gem-rebuild. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the code of conduct.

License

The gem is available as open source under the terms of the MIT License.

Code of Conduct

Everyone interacting in the gem-rebuild project's codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.