buf breaking fails when using git submodule

[ln-12]

GitHub repository with your minimal reproducible example (do not leave this field blank or fill out this field with "github.com/bufbuild/buf" or we will automatically close your issue, see the instructions above!)

https://github.com/ln-12/buf_breaking_test (app files)
https://github.com/ln-12/buf_breaking_test2 (backend files)

Commands

./generate_proto.sh

Output

Failure: Module "path: "backend_repo/protobuf", excludes: "backend_repo/protobuf/c"" had no .proto files

Expected Output

I expected no errors

Anything else?

In my project I have two sources of .proto files. One is inside app/src/main/proto (app related proto files) and the other one is backend_repo/protobuf (backend related proto files).

The app files are used for a local cache (see here) and are checked in with the rest of the app source code while the backend files are used for the communication via ConnectRPC. In my example I did not specify and rpc related messages to keep it simple and used local plugin instead of remote one as I run into rate limits while testing. Our backend files are located in a separate git repository which is shared across all devices.

The setup and workflow fit our needs quite nice but I just cannot get buf breaking to work. It always fails with some form of Module XYZ had no .proto files. Is there anything I am doing wrong or are git submodules not yet supported? While setting up this example I noticed that it seems to work perfectly fine without the submodule for the backend proto files.

[emcfarlane]

Hey @ln-12 I could reproduce the issue but it looks to be from an invalid submodule file in your config:

--- a/.gitmodules
+++ b/.gitmodules
@@ -1,3 +1,3 @@
 [submodule "backend_repo"]
        path = backend_repo
-       url = ./backend_repo/
+       url = https://github.com/ln-12/buf_breaking_test2

You will need to commit this change, and then update the generate.sh script. Because you are using submodules you'll need to set the recurse_submodule option, see the configuration docs.

buf breaking --against '.git#branch=main,recurse_submodules=true'

[ln-12]

The local submodule path was just an issue of my example, in my real project it already was set to the git url.

The missing config for me was the recurse_submodules option. I don't know why I did not see that earlier, thanks a lot for that super fast help!