How are protobuf contracts organized: where are they stored, how do you edit and compile them, where is the generated code stored?

In our practice, protobuf contracts are organized as follows:

• Where they are stored: All .proto files are stored in a separate repository or in a dedicated directory within the monorepo to ensure a single source of truth for all services.

• How we modify: Changes to .proto files go through code review and approval, as they affect multiple services. We use versioning of contracts to avoid incompatibilities.

• How we compile: To generate code, we use official protoc tools with plugins for Go (protoc-gen-go). Compilation is integrated into the CI/CD pipeline to automatically update the generated code when .proto files change.

• Where the generated code is stored: The generated Go code is stored alongside the source .proto files or in separate directories within the services that use them. In some cases, the generated code is published as a separate artifact or library so that other services can include it as a dependency.

Example of a generation command:

protoc --go_out=./gen --go_opt=paths=source_relative \
       --go-grpc_out=./gen --go-grpc_opt=paths=source_relative \
       path/to/file.proto

This approach ensures consistency, ease of maintenance, and minimizes errors when working with protobuf contracts.