influxdb/docs/regenerating_flatbuffers.md

Regenerating Flatbuffers code

If you have changed some *.fbs files:

• Run ./entry/regenerate-flatbuffers.sh to regenerate the corresponding Rust code.
• Run cargo test to make sure everything works as you would expect.
• Check in the changes to the generated code along with your changes to the *.fbs files.
• You should not need to edit the entry/regenerate-flatbuffers.sh script.

If you are updating the version of the flatbuffers crate in Cargo.lock, either because a new patch release has come out that is compatible with the version range in Cargo.toml and you have run cargo update, or because you've updated the version constraint in Cargo.toml to change to a new major or minor version:

• The flatbuffers crate gets developed in sync with the flatc compiler in the same repo, so when updating the flatbuffers crate we also need to update the flatc compiler we're using.
• Go to https://github.com/google/flatbuffers/blame/master/rust/flatbuffers/Cargo.toml and find the commit SHA where the version metadata was updated to the version of the flatbuffers crate we now want to have in our Cargo.lock.
• In the entry/regenerate-flatbuffers.sh script, put that commit SHA in the FB_COMMIT variable.
• Run ./entry/regenerate-flatbuffers.sh to regenerate the corresponding Rust code.
• Run cargo test to make sure everything works as you would expect.
• Check in the changes to the generated code along with your changes to the Cargo.lock file, Cargo.toml file if relevant, and the entry/regenerate-flatbuffers.sh script.

By default, the entry/regenerate-flatbuffers.sh script will run a Docker container that uses the same image we use in CI that will have all the necessary dependencies. If you don't want to use Docker, run this script with INFLUXDB_IOX_INTEGRATION_LOCAL=1, which will require you to have bazel available. You can likely install bazel with your favourite package manager.