add swagger docs

cmd/${REPO_NAME_SNAKE}/main.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"context"
+	_ "embed"
 	"log"
 	"net"
 	"net/http"
@@ -14,17 +15,24 @@ import (
 	"github.com/joho/godotenv"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/credentials/insecure"
+
+	"github.com/swaggest/swgui/v5emb"
 )
 
+//go:embed main.swagger.json
+var swaggerJSON []byte
+
 func main() {
 	_ = godotenv.Load()
 
+	// PostgreSQL
 	dbpool, err := pgxpool.New(context.Background(), os.Getenv("DATABASE_URL"))
 	if err != nil {
 		log.Fatalf("Unable to create connection pool: %v\n", err)
 	}
 	defer dbpool.Close()
 
+	// Test request to DB
 	var greeting string
 	if err = dbpool.QueryRow(context.Background(), "select 'Hello, world!'").Scan(&greeting); err != nil {
 		log.Fatalf("QueryRow failed: %v\n", err)
@@ -63,11 +71,22 @@ func main() {
 		log.Fatalln("Failed to register gateway:", err)
 	}
 
+	mainMux := http.NewServeMux()
+
+	docsHandler := v5emb.New("API", "/swagger/doc.json", "/docs/")
+	mainMux.Handle("/docs/", docsHandler)
+	mainMux.HandleFunc("/swagger/doc.json", func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		w.Write(swaggerJSON)
+	})
+	mainMux.Handle("/api/", gwmux)
+
 	gwServer := &http.Server{
 		Addr:    ":8090",
-		Handler: gwmux,
+		Handler: mainMux,
 	}
 
 	log.Println("Serving gRPC-Gateway on http://0.0.0.0:8090")
+	log.Println("Serving docs on http://0.0.0.0:8090/docs")
 	log.Fatalln(gwServer.ListenAndServe())
 }