http.go

package rpcserver

import (
	"log"
	"net/http"
	"path"
	"strings"

	"github.com/elazarl/go-bindata-assetfs"
	"github.com/grpc-ecosystem/grpc-gateway/runtime"
	"github.com/lxlxw/s3-micro/pkg/swagger"
	"golang.org/x/net/context"
	"google.golang.org/grpc"
	"google.golang.org/grpc/grpclog"

	gw "github.com/lxlxw/s3-micro/proto"
)

var (
	ServerHttpPort string
	HttpEndPoint   string
)

// Run httpserver.
func RunHttpServer() (err error) {
	ctx := context.Background()
	ctx, cancel := context.WithCancel(ctx)
	defer cancel()

	// grpc server
	EndPoint = ":" + ServerPort
	gwmux := runtime.NewServeMux()
	opts := []grpc.DialOption{grpc.WithInsecure()}

	// Grpc to HTTP
	err = gw.RegisterStoreApiServiceHandlerFromEndpoint(ctx, gwmux, EndPoint, opts)
	if err != nil {
		grpclog.Fatalf("Register handler err:%v\n", err)
	}

	HttpEndPoint = ":" + ServerHttpPort

	// swagger ui
	mux := http.NewServeMux()
	mux.Handle("/", gwmux)
	mux.HandleFunc("/swagger/", serveSwaggerFile)
	serveSwaggerUI(mux)

	log.Println("HTTP Listen success:", HttpEndPoint)

	s := &http.Server{
		Addr: HttpEndPoint,
		Handler: http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
			mux.ServeHTTP(w, r)
		}),
	}
	s.ListenAndServe()
	return err
}

// Swagger json file, http://localhost:port/swagger/rpc.swagger.json
func serveSwaggerFile(w http.ResponseWriter, r *http.Request) {
	if !strings.HasSuffix(r.URL.Path, "swagger.json") {
		log.Printf("Not Found: %s", r.URL.Path)
		http.NotFound(w, r)
		return
	}

	p := strings.TrimPrefix(r.URL.Path, "/swagger/")
	p = path.Join("rpc", p)

	log.Printf("Serving swagger-file: %s", p)

	http.ServeFile(w, r, p)
}

// Swagger ui, http://localhost:port/swagger-ui
func serveSwaggerUI(mux *http.ServeMux) {
	fileServer := http.FileServer(&assetfs.AssetFS{
		Asset:    swagger.Asset,
		AssetDir: swagger.AssetDir,
		Prefix:   "swagger-ui",
	})
	prefix := "/swagger-ui/"
	mux.Handle(prefix, http.StripPrefix(prefix, fileServer))
}