Here are some instructions for accomplishing specific tasks with Cogate. Please let us know if you have ideas you would like to see covered here.

Build Images with Cross-Repo-Dependencies

Cogate makes working with mulitple repositories a cinch. If you build one image from one repository, setting that up with Cogate is pretty obvious. Even building multiple images from a single repo is straightforward (just add more image stanzas).

If you build a single image from multiple git repos, Cogate has that covered too. You can even include multiple changes in a single image build by specifying cross-repo-dependencies. Cogate will check out the change for the current pull request and any dependent changes for other repos when it performs its image build.

By default Cogate runs the image build in the root of the checkout out git repo where the image is defined, and the container build context defaults to that location as well. If you want to include more than one repo, we need to tell Cogate to include both in the build context.

For example, let’s say you have an image named example/web-server. Within the web-server image, you include not only the source code for the web server (the current git repo) but you also need a git repo called example/library. To set that up in Cogate, make a cogate.yaml file in the example/web-server repo that looks like this:

- image:
    repository: example/web-server
      - example/library
    context: ~/src
    file: ~/src/

The image.required-projects attribute tells Cogate to check out the example/library git repo, and the image.context attribute says to include the entire source tree in the build context. The image.file attribute specifies which file to use to build that image.

The Dockerfile can reference any file in the context using golang-style paths when building the image.