As requirements change, you'll inevitably need to evolve your Protobuf APIs, and potentially update your dependencies.
As much as
buf's breaking change detection gives you confidence that you'll be evolving your module in a backwards
compatible way, there can still be situations in which you want to validate a change locally before pushing a new
version to the BSR.
This guide assumes that you've familiarized yourself with these topics:
1. Edit and push
buf workflow involves editing your
.proto files, and verifying the changes continue to conform to the
configured lint rules.
Once you've made your edits, you can manually verify your changes with the
buf CLI, or by
configuring your editor to automatically report errors on save.
On the command line, that should look like this:
$ buf lint $ buf generate
Once you're satisfied with the changes, save the change in your VCS (such as a Git repository) like you would with regular code. If the module is published to the BSR, you can push a new version using this command:
$ buf push --tag "$(git rev-parse HEAD)"
--tag flag isn't required, but we recommend tagging BSR commits with version control references as a way to track
2. Update dependencies
If your module has any dependencies, you can update your dependencies to their latest versions with the
buf mod update
command. This command resolves the latest commit on the repository and updates the contents of your module's
For example, if a
buf.yaml is in the current directory, you can update your
dependencies with this command:
$ buf mod update
When your dependencies conform to
buf's default lint and breaking rules,
updating is straightforward. Despite
buf's best efforts, however, dependencies sometimes undergo changes that can
break compatibility, so you might encounter errors when you try to
buf push a new version of your module to the BSR.
We encourage you to validate compatibility with
buf build after any call to
buf mod update:
# Update dependencies $ buf mod update # Verify that nothing has broken $ buf build
3. Edit multiple modules
As you develop
buf modules, you might find yourself in a situation where you own multiple modules that depend on each
other. When you want to make a change to one of your modules, you normally need to push the update up to the BSR so that
the other module can update its dependency and use it locally. This workflow imposes a frustrating feedback loop and
invites more opportunities for mistakes in each pushed module commit.
buf module workspace was created to solve exactly this problem (and more).
For example, if you have two modules checked out in sibling directories:
. ├── paymentapis │ ├── acme │ │ └── payment │ │ └── v2 │ │ └── payment.proto │ ├── buf.lock │ └── buf.yaml └── petapis ├── acme │ └── pet │ └── v1 │ └── pet.proto ├── buf.lock └── buf.yaml
version: v1 name: buf.build/acme/petapis deps: - buf.build/acme/paymentapis
version: v1 name: buf.build/acme/paymentapis
You can add a
buf.work.yaml file in the parent directory. Here's an example
. ├── buf.work.yaml ├── paymentapis │ ├── acme │ │ └── payment │ │ └── v2 │ │ └── payment.proto │ ├── buf.lock │ └── buf.yaml └── petapis ├── acme │ └── pet │ └── v1 │ └── pet.proto ├── buf.lock └── buf.yaml
version: v1 directories: - paymentapis - petapis
Now when running
buf build petapis the existence of the
buf.work.yaml file causes
buf to resolve the imports of
buf.build/acme/paymentapis with the module defined in the
paymentapis directory, rather than by using the version
fetched from the BSR according to the
buf.lock specified in the
Thus, you can make edits across both modules and immediately see the changes reflected between each module. It's
important to note that workspaces only apply to local operations. When you are ready to push updates you've made in
a local workspace, you'll need to push each module independently, starting with the upstream modules first
buf.build/acme/paymentapis in this case). Once the upstream module's changes are published, you can run the
buf mod update command in the downstream module to fetch the latest version, and continue to push each of your modules
until all of your local changes are published to the BSR.
For more on workspaces, see the workspace documentation.
buf provides a variety of powerful tools that help you develop your APIs and iterate on one or more modules at a time.
Make sure to check out more of the how-to guides to learn more!