lure/cmd/lure-api-server/main.go

package main

import (
	"context"
	"flag"
	"net"
	"net/http"
	"os"

	"github.com/twitchtv/twirp"
	"go.arsenm.dev/logger"
	"go.arsenm.dev/logger/log"
	"go.arsenm.dev/lure/internal/api"
	"go.arsenm.dev/lure/internal/repos"
)

func init() {
	log.Logger = logger.NewPretty(os.Stderr)
}

func main() {
	ctx := context.Background()

	addr := flag.String("a", ":8080", "Listen address for API server")
	logFile := flag.String("l", "", "Output file for JSON log")
	flag.Parse()

	if *logFile != "" {
		fl, err := os.Create(*logFile)
		if err != nil {
			log.Fatal("Error creating log file").Err(err).Send()
		}
		defer fl.Close()

		log.Logger = logger.NewMulti(log.Logger, logger.NewJSON(fl))
	}

	err := repos.Pull(ctx, gdb, cfg.Repos)
	if err != nil {
		log.Fatal("Error pulling repositories").Err(err).Send()
	}

	sigCh := make(chan struct{}, 200)
	go repoPullWorker(ctx, sigCh)

	var handler http.Handler

	handler = api.NewAPIServer(
		lureWebAPI{db: gdb},
		twirp.WithServerPathPrefix(""),
	)
	handler = withAcceptLanguage(handler)
	handler = allowAllCORSHandler(handler)
	handler = handleWebhook(handler, sigCh)

	ln, err := net.Listen("tcp", *addr)
	if err != nil {
		log.Fatal("Error starting listener").Err(err).Send()
	}

	log.Info("Starting HTTP API server").Str("addr", ln.Addr().String()).Send()

	err = http.Serve(ln, handler)
	if err != nil {
		log.Fatal("Error while running server").Err(err).Send()
	}
}

func allowAllCORSHandler(h http.Handler) http.Handler {
	return http.HandlerFunc(func(res http.ResponseWriter, req *http.Request) {
		res.Header().Set("Access-Control-Allow-Origin", "*")
		res.Header().Set("Access-Control-Allow-Headers", "*")
		if req.Method == http.MethodOptions {
			return
		}
		h.ServeHTTP(res, req)
	})
}

type (
	acceptLanguageKey struct{}
	langParameterKey  struct{}
)

func withAcceptLanguage(h http.Handler) http.Handler {
	return http.HandlerFunc(func(res http.ResponseWriter, req *http.Request) {
		ctx := req.Context()

		langs := req.Header.Get("Accept-Language")
		ctx = context.WithValue(ctx, acceptLanguageKey{}, langs)

		lang := req.URL.Query().Get("lang")
		ctx = context.WithValue(ctx, langParameterKey{}, lang)

		req = req.WithContext(ctx)

		h.ServeHTTP(res, req)
	})
}