handler: Emit pre-finish hook for concatenated uploads

Fixes #1169.

pkg/handler/concat_test.go

@@ -148,6 +148,14 @@ func TestConcat(t *testing.T) {
 				BasePath:              "files",
 				StoreComposer:         composer,
 				NotifyCompleteUploads: true,
+				PreFinishResponseCallback: func(hook HookEvent) (HTTPResponse, error) {
+					a.Equal("foo", hook.Upload.ID)
+					return HTTPResponse{
+						Header: HTTPHeader{
+							"X-Custom-Resp-Header": "hello",
+						},
+					}, nil
+				},
 			})
 
 			c := make(chan HookEvent, 1)
@@ -160,10 +168,13 @@ func TestConcat(t *testing.T) {
 					// A space between `final;` and the first URL should be allowed due to
 					// compatibility reasons, even if the specification does not define
 					// it. Therefore this character is included in this test case.
-					"Upload-Concat":   "final; http://tus.io/files/a /files/b/",
-					"X-Custom-Header": "tada",
+					"Upload-Concat":       "final; http://tus.io/files/a /files/b/",
+					"X-Custom-Req-Header": "tada",
 				},
 				Code: http.StatusCreated,
+				ResHeader: map[string]string{
+					"X-Custom-Resp-Header": "hello",
+				},
 			}).Run(handler, t)
 
 			event := <-c
@@ -178,7 +189,7 @@ func TestConcat(t *testing.T) {
 			req := event.HTTPRequest
 			a.Equal("POST", req.Method)
 			a.Equal("", req.URI)
-			a.Equal("tada", req.Header.Get("X-Custom-Header"))
+			a.Equal("tada", req.Header.Get("X-Custom-Req-Header"))
 		})
 
 		SubTest(t, "Status", func(t *testing.T, store *MockFullDataStore, composer *StoreComposer) {

pkg/handler/unrouted_handler.go

@@ -410,8 +410,10 @@ func (handler *UnroutedHandler) PostFile(w http.ResponseWriter, r *http.Request)
 		}
 		info.Offset = size
 
-		if handler.config.NotifyCompleteUploads {
-			handler.CompleteUploads <- newHookEvent(c, info)
+		resp, err = handler.emitFinishEvents(c, resp, info)
+		if err != nil {
+			handler.sendError(c, err)
+			return
 		}
 	}
 
@@ -936,31 +938,42 @@ func (handler *UnroutedHandler) writeChunk(c *httpContext, resp HTTPResponse, up
 
 // finishUploadIfComplete checks whether an upload is completed (i.e. upload offset
 // matches upload size) and if so, it will call the data store's FinishUpload
-// function and send the necessary message on the CompleteUpload channel.
+// function and emit the necessary events for the hooks.
 func (handler *UnroutedHandler) finishUploadIfComplete(c *httpContext, resp HTTPResponse, upload Upload, info FileInfo) (HTTPResponse, error) {
 	// If the upload is completed, ...
 	if !info.SizeIsDeferred && info.Offset == info.Size {
+		var err error
 		// ... allow the data storage to finish and cleanup the upload
-		if err := upload.FinishUpload(c); err != nil {
+		if err = upload.FinishUpload(c); err != nil {
 			return resp, err
 		}
 
-		// ... allow the hook callback to run before sending the response
-		if handler.config.PreFinishResponseCallback != nil {
-			resp2, err := handler.config.PreFinishResponseCallback(newHookEvent(c, info))
-			if err != nil {
-				return resp, err
-			}
-			resp = resp.MergeWith(resp2)
+		// ... and call pre-finish callback and send post-finish notification.
+		resp, err = handler.emitFinishEvents(c, resp, info)
+		if err != nil {
+			return resp, err
 		}
+	}
 
-		c.log.Info("UploadFinished", "size", info.Size)
-		handler.Metrics.incUploadsFinished()
+	return resp, nil
+}
 
-		// ... send the info out to the channel
-		if handler.config.NotifyCompleteUploads {
-			handler.CompleteUploads <- newHookEvent(c, info)
+// emitFinishEvents calls the PreFinishResponseCallback function and sends
+// the necessary message on the CompleteUpload channel.
+func (handler *UnroutedHandler) emitFinishEvents(c *httpContext, resp HTTPResponse, info FileInfo) (HTTPResponse, error) {
+	if handler.config.PreFinishResponseCallback != nil {
+		resp2, err := handler.config.PreFinishResponseCallback(newHookEvent(c, info))
+		if err != nil {
+			return resp, err
 		}
+		resp = resp.MergeWith(resp2)
+	}
+
+	c.log.Info("UploadFinished", "size", info.Size)
+	handler.Metrics.incUploadsFinished()
+
+	if handler.config.NotifyCompleteUploads {
+		handler.CompleteUploads <- newHookEvent(c, info)
 	}
 
 	return resp, nil