Refactor: extract main and AppEngine routers (#18)

appengine/main.go

@@ -3,25 +3,11 @@ package main
 import (
 	"net/http"
 
-	gh "github.com/gorilla/handlers"
-	"github.com/gorilla/mux"
-	"github.com/int128/jira-to-slack/pkg/handlers"
+	aeRouter "github.com/int128/jira-to-slack/pkg/router/appengine"
 	"google.golang.org/appengine"
-	"google.golang.org/appengine/urlfetch"
 )
 
-func router() http.Handler {
-	m := mux.NewRouter()
-	m.Handle("/", &handlers.Index{}).Methods("GET")
-	m.Handle("/", gh.ContentTypeHandler(&handlers.Webhook{
-		HTTPClientFactory: func(r *http.Request) *http.Client {
-			return urlfetch.Client(r.Context())
-		},
-	}, "application/json")).Methods("POST")
-	return m
-}
-
 func main() {
-	http.Handle("/", router())
+	http.Handle("/", aeRouter.New())
 	appengine.Main()
 }

main.go

@@ -5,26 +5,13 @@ import (
 	"net/http"
 	"os"
 
-	gh "github.com/gorilla/handlers"
-	"github.com/gorilla/mux"
-	"github.com/int128/jira-to-slack/pkg/handlers"
+	"github.com/int128/jira-to-slack/pkg/router"
 )
 
 var version string
 
 const defaultPort = "3000"
 
-func router() http.Handler {
-	r := mux.NewRouter()
-	r.Handle("/", &handlers.Index{}).Methods("GET")
-	r.Handle("/", gh.ContentTypeHandler(&handlers.Webhook{}, "application/json")).Methods("POST")
-
-	m := http.NewServeMux()
-	m.Handle("/", gh.LoggingHandler(os.Stdout, r))
-	m.Handle("/healthz", &handlers.Healthz{})
-	return m
-}
-
 func main() {
 	log.Printf("jira-to-slack %s", version)
 
@@ -35,7 +22,7 @@ func main() {
 	addr := ":" + port
 
 	log.Printf("Listening on %s", addr)
-	if err := http.ListenAndServe(addr, router()); err != nil {
+	if err := http.ListenAndServe(addr, router.New()); err != nil {
 		log.Fatalf("Error while listening on %s: %s", addr, err)
 	}
 }

pkg/handlers/webhook.go

@@ -1,6 +1,7 @@
 package handlers
 
 import (
+	"context"
 	"encoding/json"
 	"fmt"
 	"log"
@@ -14,7 +15,7 @@ import (
 
 // Webhook handles requests from JIRA webhook.
 type Webhook struct {
-	HTTPClientFactory func(*http.Request) *http.Client // Default to http.DefaultClient
+	HTTPClientFactory func(context.Context) *http.Client // Default to http.DefaultClient
 }
 
 type WebhookParams struct {
@@ -85,7 +86,7 @@ func (h *Webhook) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	}
 	var hc *http.Client
 	if h.HTTPClientFactory != nil {
-		hc = h.HTTPClientFactory(r)
+		hc = h.HTTPClientFactory(ctx)
 	}
 
 	in := usecases.WebhookIn{

pkg/router/appengine/router.go

@@ -0,0 +1,27 @@
+package appengine
+
+import (
+	"context"
+	"net/http"
+
+	gh "github.com/gorilla/handlers"
+	"github.com/gorilla/mux"
+	"github.com/int128/jira-to-slack/pkg/handlers"
+	"google.golang.org/appengine/urlfetch"
+)
+
+func httpClientFactory(ctx context.Context) *http.Client {
+	return urlfetch.Client(ctx)
+}
+
+func New() http.Handler {
+	m := mux.NewRouter()
+	m.Handle("/", &handlers.Index{}).Methods("GET")
+	m.Handle("/",
+		gh.ContentTypeHandler(
+			&handlers.Webhook{HTTPClientFactory: httpClientFactory},
+			"application/json",
+		),
+	).Methods("POST")
+	return m
+}

appengine/main_test.go → pkg/router/appengine/router_test.go

@@ -1,13 +1,13 @@
-package main
+package appengine
 
 import (
 	"net/http"
 	"net/http/httptest"
 	"testing"
 )
 
-func TestRouter(t *testing.T) {
-	s := httptest.NewServer(router())
+func TestNew(t *testing.T) {
+	s := httptest.NewServer(New())
 	defer s.Close()
 
 	t.Run("index", func(t *testing.T) {

pkg/router/router.go

@@ -0,0 +1,21 @@
+package router
+
+import (
+	"net/http"
+	"os"
+
+	gh "github.com/gorilla/handlers"
+	"github.com/gorilla/mux"
+	"github.com/int128/jira-to-slack/pkg/handlers"
+)
+
+func New() http.Handler {
+	r := mux.NewRouter()
+	r.Handle("/", &handlers.Index{}).Methods("GET")
+	r.Handle("/", gh.ContentTypeHandler(&handlers.Webhook{}, "application/json")).Methods("POST")
+
+	m := http.NewServeMux()
+	m.Handle("/", gh.LoggingHandler(os.Stdout, r))
+	m.Handle("/healthz", &handlers.Healthz{})
+	return m
+}

main_test.go → pkg/router/router_test.go

@@ -1,13 +1,13 @@
-package main
+package router
 
 import (
 	"net/http"
 	"net/http/httptest"
 	"testing"
 )
 
-func TestRouter(t *testing.T) {
-	s := httptest.NewServer(router())
+func TestNew(t *testing.T) {
+	s := httptest.NewServer(New())
 	defer s.Close()
 
 	t.Run("index", func(t *testing.T) {