Protobuf Refactoring for Multi-Module Cleanliness
This commit includes the following:
Moves all packages that were within proto/ to proto/private
Rewrites imports to account for the packages being moved
Adds in buf.work.yaml to enable buf workspaces
Names the proto-public buf module so that we can override the Go package imports within proto/buf.yaml
Bumps the buf version dependency to 1.14.0 (I was trying out the version to see if it would get around an issue - it didn't but it also doesn't break things and it seemed best to keep up with the toolchain changes)
Why:
In the future we will need to consume other protobuf dependencies such as the Google HTTP annotations for openapi generation or grpc-gateway usage.
There were some recent changes to have our own ratelimiting annotations.
The two combined were not working when I was trying to use them together (attempting to rebase another branch)
Buf workspaces should be the solution to the problem
Buf workspaces means that each module will have generated Go code that embeds proto file names relative to the proto dir and not the top level repo root.
This resulted in proto file name conflicts in the Go global protobuf type registry.
The solution to that was to add in a private/ directory into the path within the proto/ directory.
That then required rewriting all the imports.
Is this safe?
AFAICT yes
The gRPC wire protocol doesn't seem to care about the proto file names (although the Go grpc code does tack on the proto file name as Metadata in the ServiceDesc)
Other than imports, there were no changes to any generated code as a result of this.
Adds automation for generating the map of `gRPC Method Name → Rate Limit Type`
used by the middleware introduced in #15550, and will ensure we don't forget
to add new endpoints.
Engineers must annotate their RPCs in the proto file like so:
```
rpc Foo(FooRequest) returns (FooResponse) {
option (consul.internal.ratelimit.spec) = {
operation_type: READ,
};
}
```
When they run `make proto` a protoc plugin `protoc-gen-consul-rate-limit` will
be installed that writes rate-limit specs as a JSON array to a file called
`.ratelimit.tmp` (one per protobuf package/directory).
After running Buf, `make proto` will execute a post-process script that will
ingest all of the `.ratelimit.tmp` files and generate a Go file containing the
mappings in the `agent/grpc-middleware` package. In the enterprise repository,
it will write an additional file with the enterprise-only endpoints.
If an engineer forgets to add the annotation to a new RPC, the plugin will
return an error like so:
```
RPC Foo is missing rate-limit specification, fix it with:
import "proto-public/annotations/ratelimit/ratelimit.proto";
service Bar {
rpc Foo(...) returns (...) {
option (hashicorp.consul.internal.ratelimit.spec) = {
operation_type: OPERATION_READ | OPERATION_WRITE | OPERATION_EXEMPT,
};
}
}
```
In the future, this annotation can be extended to support rate-limit
category (e.g. KV vs Catalog) and to determine the retry policy.
Matt Keeler
Dan Upton