Implement HTTP service stop with a 5 sec timeout (#209)

* Implement HTTP service stop with a 5 sec timeout

* No need to wrap the cancellation in an extra func

* Address lint errors, camel case variables

service/http/service.go

@@ -1,7 +1,9 @@
 package http
 
 import (
+	"context"
 	"net/http"
+	"time"
 
 	"github.com/dapr/go-sdk/service/common"
 )
@@ -21,7 +23,11 @@ func newServer(address string, mux *http.ServeMux) *Server {
 		mux = http.NewServeMux()
 	}
 	return &Server{
-		address:            address,
+		address: address,
+		httpServer: &http.Server{
+			Addr:    address,
+			Handler: mux,
+		},
 		mux:                mux,
 		topicSubscriptions: make([]*common.Subscription, 0),
 	}
@@ -31,23 +37,22 @@ func newServer(address string, mux *http.ServeMux) *Server {
 type Server struct {
 	address            string
 	mux                *http.ServeMux
+	httpServer         *http.Server
 	topicSubscriptions []*common.Subscription
 }
 
 // Start starts the HTTP handler. Blocks while serving.
 func (s *Server) Start() error {
 	s.registerSubscribeHandler()
-	server := http.Server{
-		Addr:    s.address,
-		Handler: s.mux,
-	}
-	return server.ListenAndServe()
+	return s.httpServer.ListenAndServe()
 }
 
-// Stop stops previously started HTTP service.
+// Stop stops previously started HTTP service with a five second timeout.
 func (s *Server) Stop() error {
-	// TODO: implement service stop
-	return nil
+	ctxShutDown, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	return s.httpServer.Shutdown(ctxShutDown)
 }
 
 func setOptions(w http.ResponseWriter, r *http.Request) {

service/http/service_test.go

@@ -4,6 +4,7 @@ import (
 	"net/http"
 	"net/http/httptest"
 	"testing"
+	"time"
 
 	"github.com/stretchr/testify/assert"
 )
@@ -15,6 +16,31 @@ func TestStoppingUnstartedService(t *testing.T) {
 	assert.NoError(t, err)
 }
 
+func TestStoppingStartedService(t *testing.T) {
+	s := newServer(":3333", nil)
+	assert.NotNil(t, s)
+
+	go func() {
+		if err := s.Start(); err != nil && err != http.ErrServerClosed {
+			panic(err)
+		}
+	}()
+	// Wait for the server to start
+	time.Sleep(200 * time.Millisecond)
+	assert.NoError(t, s.Stop())
+}
+
+func TestStartingStoppedService(t *testing.T) {
+	s := newServer(":3333", nil)
+	assert.NotNil(t, s)
+	stopErr := s.Stop()
+	assert.NoError(t, stopErr)
+
+	startErr := s.Start()
+	assert.Error(t, startErr, "expected starting a stopped server to raise an error")
+	assert.Equal(t, startErr.Error(), http.ErrServerClosed.Error())
+}
+
 func TestSettingOptions(t *testing.T) {
 	req, err := http.NewRequest(http.MethodOptions, "/", nil)
 	assert.NoErrorf(t, err, "error creating request")