Create Patches

You can manually modify an external dependency to:

  • Make sure that dependency works with Omnibus embedded packaging.
  • Fix an issue that an upstream maintainer has not fixed.

Bootstrap patch files

Omnibus has a specific DSL and conventions to ship and apply patches automatically as part of the build process.

To apply patch files, store .patch files that contain the changes in a specific directory structure using the patch DSL method: 

config/patches/<software-name>

For example, for a patch applied during the execution of gitlab-rails, store the .patch files in: 

config/patches/gitlab-rails

Create a patch

To create a patch file, you can use:

  • The diff command to compare an original file with a modified file.
  • Git to output a patch based one or more commits.

Use diff to create a patch

To create a patch file using the diff command:

  1. Duplicate the file you are changing and give the new file a new name.
  2. Change the original file. 
diff -Naur <original_file> <new_file> > <patch_filename>.patch

Use Git to create a patch

Use the git diff command to create a patch file between two Git commits. You must know both commit IDs. 

git diff <commitid1> <commitid2> > <patch_filename>.patch

You can also create a patch file based on one Git commit and the base HEAD. 

git diff <commitid1> > <patch_filename>.patch

Use the patch

To patch one or more files:

  1. Get the original files by downloading, bundle installing, or using a similar method.

  2. Add the following line to each original file: 

    patch source: '<patch_filename>.patch', target: "#{<install_directory>}/embedded/<target_file>.txt"