Gateway Setup

The gateway runs as a separate process that proxies HTTP/JSON requests to your gRPC server.

`cmd/gateway/main.go`

package main

import (
	"context"
	"fmt"
	"log"
	"net/http"

	"github.com/grpc-ecosystem/grpc-gateway/v2/runtime"
	"google.golang.org/grpc"
	"google.golang.org/grpc/credentials/insecure"

	"shortener/pb"
)

func main() {
	ctx := context.Background()
	mux := runtime.NewServeMux()

	err := pb.RegisterLinkServiceHandlerFromEndpoint(ctx, mux, "localhost:50051",
		[]grpc.DialOption{grpc.WithTransportCredentials(insecure.NewCredentials())},
	)
	if err != nil {
		log.Fatal(err)
	}

	fmt.Println("HTTP gateway on :8080")
	log.Fatal(http.ListenAndServe(":8080", mux))
}

Running

Start the gRPC server first, then the gateway in a second terminal:

# Terminal 1
go run .

# Terminal 2
go run ./cmd/gateway/

Test with curl

curl -X POST http://localhost:8080/v1/links -d '{"url":"https://golang.org"}'
curl http://localhost:8080/v1/links/abc123