internal/pkg/rsproxy/prototext_reader.go

// Copyright 2026 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package rsproxy

import (
	"context"
	"fmt"
	"os"

	"github.com/bazelbuild/rsclient/internal/pkg/protoutil"
	"github.com/golang/glog"

	rspb "google.golang.org/genproto/googleapis/devtools/resultstore/v2"
)

// PrototextDelimiter is the marker used to separate individual Prototext messages in a stream.
const PrototextDelimiter = "# ---- ResultStore v2 UploadRequest ----"

var uploadRequestIO = protoutil.NewDelimitedPrototextIO((*rspb.UploadRequest)(nil), protoutil.DelimitedPrototextConfig{
	Delimiter: PrototextDelimiter,
})

// PrototextReaderOptions contains configuration for a Prototext-based ingress.
type PrototextReaderOptions struct {
	// Path is the filesystem path to the Prototext file.
	Path string
}

// prototextReader reads human-readable prototext messages from a file.
// It expects each request to be preceded by PrototextDelimiter.
type prototextReader struct {
	path string
}

func NewPrototextReader(path string) IngressWorker {
	return &prototextReader{path: path}
}

func (w *prototextReader) Name() string {
	return "PrototextReader"
}

func (w *prototextReader) Run(ctx context.Context, outbound chan<- *rspb.UploadRequest, ea ErrorAggregator) error {
	f, err := os.Open(w.path)
	if err != nil {
		return fmt.Errorf("failed to open prototext reader file %q: %w", w.path, err)
	}
	defer f.Close()

	glog.Infof("PrototextReader: reading from %q", w.path)

	handle := func(req *rspb.UploadRequest) error {
		select {
		case <-ctx.Done():
			return ctx.Err()
		case outbound <- req:
			return nil
		}
	}

	if err := uploadRequestIO.ReadStream(ctx, f, handle); err != nil {
		return fmt.Errorf("prototext stream failed: %w", err)
	}

	glog.Infof("PrototextReader: finished reading %q", w.path)
	return nil
}