Adding debugging for webhook (#7199)

* Adding debugging for webhook

* Fixing build error

* Moving error down

api4/webhook.go

@@ -476,7 +476,12 @@ func incomingWebhook(c *Context, w http.ResponseWriter, r *http.Request) {
 		}
 	}
 
-	parsedRequest := model.IncomingWebhookRequestFromJson(payload)
+	parsedRequest, decodeError := model.IncomingWebhookRequestFromJson(payload)
+
+	if decodeError != nil {
+		c.Err = decodeError
+		return
+	}
 
 	err := app.HandleIncomingWebhook(id, parsedRequest)
 	if err != nil {

model/incoming_webhook.go

@@ -193,7 +193,7 @@ func decodeIncomingWebhookRequest(by []byte) (*IncomingWebhookRequest, error) {
 	}
 }
 
-func IncomingWebhookRequestFromJson(data io.Reader) *IncomingWebhookRequest {
+func IncomingWebhookRequestFromJson(data io.Reader) (*IncomingWebhookRequest, *AppError) {
 	buf := new(bytes.Buffer)
 	buf.ReadFrom(data)
 	by := buf.Bytes()
@@ -204,12 +204,12 @@ func IncomingWebhookRequestFromJson(data io.Reader) *IncomingWebhookRequest {
 	if err != nil {
 		o, err = decodeIncomingWebhookRequest(escapeControlCharsFromPayload(by))
 		if err != nil {
-			return nil
+			return nil, NewAppError("IncomingWebhookRequestFromJson", "Unable to parse incoming data", nil, err.Error(), http.StatusBadRequest)
 		}
 	}
 
 	o.Text = ExpandAnnouncement(o.Text)
 	o.Attachments = ProcessSlackAttachments(o.Attachments)
 
-	return o
+	return o, nil
 }

model/incoming_webhook_test.go

@@ -108,7 +108,7 @@ func TestIncomingWebhookRequestFromJson_Announcements(t *testing.T) {
 	// simple payload
 	payload := `{"text": "` + text + `"}`
 	data := strings.NewReader(payload)
-	iwr := IncomingWebhookRequestFromJson(data)
+	iwr, _ := IncomingWebhookRequestFromJson(data)
 
 	if iwr == nil {
 		t.Fatal("IncomingWebhookRequest should not be nil")
@@ -136,7 +136,7 @@ func TestIncomingWebhookRequestFromJson_Announcements(t *testing.T) {
 		}`
 
 	data = strings.NewReader(payload)
-	iwr = IncomingWebhookRequestFromJson(data)
+	iwr, _ = IncomingWebhookRequestFromJson(data)
 
 	if iwr == nil {
 		t.Fatal("IncomingWebhookRequest should not be nil")
@@ -213,7 +213,7 @@ func TestIncomingWebhookRequestFromJson(t *testing.T) {
 
 		// try to create an IncomingWebhookRequest from the payload
 		data := strings.NewReader(payload)
-		iwr := IncomingWebhookRequestFromJson(data)
+		iwr, _ := IncomingWebhookRequestFromJson(data)
 
 		// After it has been decoded, the JSON string won't contain the escape char anymore
 		expected := strings.Replace(text, `\"`, `"`, -1)
@@ -233,7 +233,7 @@ func TestIncomingWebhookRequestFromJson(t *testing.T) {
 
 func TestIncomingWebhookNullArrayItems(t *testing.T) {
 	payload := `{"attachments":[{"fields":[{"title":"foo","value":"bar","short":true}, null]}, null]}`
-	iwr := IncomingWebhookRequestFromJson(strings.NewReader(payload))
+	iwr, _ := IncomingWebhookRequestFromJson(strings.NewReader(payload))
 	if iwr == nil {
 		t.Fatal("IncomingWebhookRequest should not be nil")
 	}