Search code examples
gitgit-submodulesrepositorygit-slave

What are the options when working with Git submodules from which commits are made?

At work, we're working on a dozen Java OSGi bundles, each of which has its own git repository. All bundles will be, in the long run, pretty independent from each other, which justifies the individual repositories — although right now we're still often modifying several of them at the same time.

When we make a product release (which consists of all bundles), a new branch is created in each bundle, which is a bit of a pain. We were thus thinking about using git-submodule to ease the pain (something like git submodule foreach <cmd>).

So, our desired setup would be a master project Product, and submodules for each bundle:

Project/
  BundleA/
  BundleB/
  BundleC/

Now, I've spent several hours reading all I could find about submodules, and I understood that if I modify things in BundleA, I have to commit in BundleA, push, then commit the submodule change in Project and push again.

This clearly sounds like it was not how git-submodule was designed to be used in the first place. Is it against best practices to use it like this? Or does it sound like a case where an alternative would be preferred?

  • bare-bones git-submodule usage
  • using an existing “git wrapper”:
  • write my own simple bash scripts to batch process the OSGi bundles

Any other suggestion welcome.

Solution

  • If you do not need to keep track of what the subproject is doing in the superproject (tight binding) then I recommend you stay far away from git-submodules.

    gitslave (http://gitslave.sf.net) is essentially a large foreach around each of the subprojects with a config file in the superproject listing the subprojects. There are lots of bells and whistles which make it more convenient, but if your goal is to run the same command on the superproject (optional) and all of the subprojects, gitslave is about as convenient as you are going to find.

    So for example, to create a new branch in gitslave is:

    gits checkout -b newbr

    Then your superproject and all of the subprojects will create the new branch and change to it. In general, if you want to run a gits command on all members of the superproject, just change the "git" command to "gits".