Dan Upton d4c435856b
grpc: protoc plugin for generating gRPC rate limit specifications (#15564)
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.
2023-01-04 16:07:02 +00:00

49 lines
1.1 KiB
Go

package main
import (
"flag"
"os"
"path/filepath"
"testing"
"github.com/stretchr/testify/require"
)
// update allows golden files to be updated based on the current output.
var update = flag.Bool("update", false, "update golden files")
func TestE2E(t *testing.T) {
// Generate new output
*flagPath = "./e2e/source.pb.go"
require.NoError(t, run(*flagPath))
raw, err := os.ReadFile("./e2e/source.rpcglue.pb.go")
require.NoError(t, err)
got := string(raw)
golden(t, got, "./e2e/source.rpcglue.pb.go")
}
// golden reads the expected value from the file at path and returns the
// value.
//
// If the `-update` flag is used with `go test`, the golden file will be
// updated to the value of actual.
func golden(t *testing.T, actual, path string) string {
t.Helper()
path += ".golden"
if *update {
if dir := filepath.Dir(path); dir != "." {
require.NoError(t, os.MkdirAll(dir, 0755))
}
err := os.WriteFile(path, []byte(actual), 0644)
require.NoError(t, err)
}
expected, err := os.ReadFile(path)
require.NoError(t, err)
return string(expected)
}