Add support for deleted mentions

storage.go

@@ -14,6 +14,7 @@ import (
 type Storage interface {
 	CreateFile(path string, file string, message string) (err error)
 	UpdateFile(path string, file string, message string) (err error)
+	DeleteFile(path string, message string) (err error)
 }
 
 type Git struct {
@@ -134,4 +135,31 @@ func (g Git) UpdateFile(filepath string, file string, message string) error {
 		return errors.New("failed to commit file")
 	}
 	return g.push(repo)
-}
+}
+
+func (g Git) DeleteFile(filepath string, message string) (err error) {
+	repo, w, err := g.init()
+	if err != nil {
+		return errors.New("failed to initialize repo")
+	}
+	joinedPath := path.Join(g.filepath, filepath)
+	err = os.Remove(joinedPath)
+	if err != nil {
+		return errors.New("failed to delete file")
+	}
+	_, err = w.Add(filepath)
+	if err != nil {
+		return errors.New("failed to stage deletion")
+	}
+	_, err = w.Commit(message, &git.CommitOptions{
+		Author: &object.Signature{
+			Name:  g.name,
+			Email: g.email,
+			When:  time.Now(),
+		},
+	})
+	if err != nil {
+		return errors.New("failed to commit deletion")
+	}
+	return g.push(repo)
+}

webmention.go

@@ -103,9 +103,14 @@ func HandleWebmention(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 	if respCode < 200 || respCode >= 300 {
-		if respCode == 410 {
+		if respCode == 410 || respCode == 404 {
 			// Delete mention, because source is gone
-			// TODO: Implement deletion
+			go func() {
+				e := deleteWebmention(sourceUrl.String(), targetUrl.String())
+				if e != nil {
+					fmt.Print("Tried to delete webmention", sourceUrl.String(), "but failed:", e.Error())
+				}
+			}()
 			returnSuccess(targetUrl.String(), w, r)
 			return
 		} else {
@@ -118,21 +123,27 @@ func HandleWebmention(w http.ResponseWriter, r *http.Request) {
 	// Check if source mentions target
 	if !sourceMentionsTarget(sourceUrl.String(), targetUrl.String()) {
 		err = errors.New("source doesn't mention target")
+		go func() {
+			// Try to delete webmention nevertheless
+			e := deleteWebmention(sourceUrl.String(), targetUrl.String())
+			if e != nil {
+				fmt.Print("Tried to delete webmention (source doesn't mention target) ", sourceUrl.String(), "but failed:", e.Error())
+			}
+		}()
 		w.WriteHeader(http.StatusBadRequest)
 		_, _ = w.Write([]byte(err.Error()))
 		return
 	}
-	mention := &Mention{
-		Source: sourceUrl.String(),
-		Target: targetUrl.String(),
-		Date:   time.Now().Format(time.RFC3339),
-	}
-	err = saveWebmention(mention)
-	if err != nil {
-		w.WriteHeader(http.StatusInternalServerError)
-		_, _ = w.Write([]byte(err.Error()))
-		return
-	}
+	go func() {
+		e := saveWebmention(&Mention{
+			Source: sourceUrl.String(),
+			Target: targetUrl.String(),
+			Date:   time.Now().Format(time.RFC3339),
+		})
+		if e != nil {
+			fmt.Println("Failed to save webmention:", e.Error())
+		}
+	}()
 	returnSuccess(targetUrl.String(), w, r)
 	go func() {
 		if SelectedNotificationServices != nil {
@@ -175,13 +186,19 @@ func saveWebmention(mention *Mention) (err error) {
 	return
 }
 
+func deleteWebmention(source string, target string) (err error) {
+	filePath := fmt.Sprintf("data/mentions/%x/%x.json", md5.Sum([]byte(strings.ReplaceAll(target, "/", ""))), md5.Sum([]byte(source)))
+	err = SelectedStorage.DeleteFile(filePath, "Delete webmention from "+source)
+	return
+}
+
 func returnSuccess(target string, w http.ResponseWriter, r *http.Request) {
+	w.Header().Add("Location", target)
 	if strings.Contains(r.Header.Get("Accept"), "text/html") {
 		// Redirect browser
-		w.Header().Add("Location", target)
 		w.WriteHeader(http.StatusSeeOther)
 	} else {
-		w.WriteHeader(http.StatusOK)
+		w.WriteHeader(http.StatusCreated)
 	}
 	// Purge CDN after 30 seconds
 	go func() {