toolkit/cmd/otelq/main.go

package main

import (
	"flag"
	"fmt"
	"io"
	"log"
	"os"

	tracev1 "go.opentelemetry.io/proto/otlp/trace/v1"
	"google.golang.org/protobuf/encoding/protojson"
	"google.golang.org/protobuf/proto"
)

var (
	file = flag.String("file", "", "OpenTelemetry proto file. if set, will not use stdin.")
)

func main() {
	flag.Parse()

	if *file != "" {
		fmt.Fprintf(os.Stderr, "reading file %s\n", *file)
		h := must(os.Open(*file))
		bs := must(io.ReadAll(h))

		var td tracev1.TracesData
		if err := proto.Unmarshal(bs, &td); err != nil {
			log.Fatalln(err)
		}

		jsonbs, err := protojson.Marshal(&td)
		if err != nil {
			log.Fatalln(err)
		}

		fmt.Fprint(os.Stdout, string(jsonbs))
	} else {
		fmt.Println("using stdin")
	}
}

func must[T any](v T, err error) T {
	if err != nil {
		log.Fatalln(err)
	}
	return v
}