With bundler it's easy for your project to depend on many gems. This decomposition is nice, but managing licenses becomes difficult. This tool gathers info about the licenses of the gems in your project.
Add license_finder to your Rails project's Gemfile and
License finder will generate reports of action items - i.e., dependencies that do not fall within your license "whitelist".
$ bundle exec license_finder
The first time you run this,
license_finder will create a default configuration file
--- whitelist: #- MIT #- Apache 2.0 ignore_groups: #- test #- development
This allows you to configure bundler groups and add licenses to the whitelist.
On a brand new Rails project, you could expect
license_finder to output something like the following
(assuming you whitelisted the MIT license in your
Dependencies that need approval: highline, 1.6.14, ruby json, 1.7.5, ruby mime-types, 1.19, ruby rails, 3.2.8, other rdoc, 3.12, other rubyzip, 0.9.9, ruby xml-simple, 1.1.1, other
The executable task will also write out a dependencies.yml, dependencies.txt, and dependencies.html file in the root of your project.
The latter two files are human readable reports that you could send to your non-technical business partners, lawyers, etc.
license_finder will also return a non-zero exit status if there are
unapproved dependencies. You could use this in a CI build, for example, to alert you whenever someone adds an
unapproved dependency to the project.
It will also merge in an existing dependencies.yml file, if one exists (i.e., you've previously run this command and then edited the resulting file).
Manually recording licenses
When you have dependencies marked as having an 'other' license,
license_finder will output
the license and readme file locations for the dependency, allowing you to manually research what the actual
license is. Once this has been established, you can record this information with the
$ license_finder -l MIT my_unknown_dependency
This command would assign the MIT license to the dependency
Manually approving dependencies
Whenever you have a dependency that falls outside of your whitelist,
license_finder will tell you.
If your business decides that this is an acceptable risk, you can manually approve the dependency by using the
--approve option of the
For example, lets assume you've only
whitelisted the "MIT" license in your
config/license_finder.yml. You then add the 'awesome_gpl_gem' to your Gemfile,
which we'll assume is licensed with the
GPL license. You then run
license_finder and see
the gem listed in the output:
awesome_gpl_gem, 1.0.0, GPL
Your business tells you that in this case, it's acceptable to use this gem. You now run:
$ bundle exec license_finder -a awesome_gpl_gem
If you rerun
license_finder, you should no longer see
awesome_gpl_gem in the output.
You could then update the "approved" attribute to true once you have signoff from your business. License Finder will remember any manually added licenses between successive runs.
Usage with Rake
First, add license finder to your project's Gemfile:
Next, update your project's Rakefile with the license finder rake task:
require 'bundler/setup' require 'license_finder' LicenseFinder.load_rake_tasks
You can now run
bundle exec rake license_finder. This is the equivalent of running
bundle exec license_finder.
This could be handy if you have a build for CI that you want to break when you have unapproved dependencies. The
rake task will
exit 1 immediately if there are unapproved dependencies, stopping your build dead in its tracks!
A note to gem authors / maintainers
For the good of humanity, please add a license to your gemspec!
Gem::Specification.new do |s| s.name = "my_great_gem" s.license = "MIT" end
And add a
LICENSE file to your gem that contains your license text.
LicenseFinder is released under the MIT License. http://www.opensource.org/licenses/mit-license