Show error messages in UI if something goes wrong

cmd/backend/images.go

@@ -2,6 +2,7 @@ package backend
 
 import (
 	"fmt"
+	"image"
 	"io"
 	"os"
 
@@ -10,9 +11,14 @@ import (
 	"github.com/google/uuid"
 )
 
+var ErrUnsupportedFormat error = image.ErrFormat // used internally by imaging
+
 func SaveImage(c *Config, src io.Reader) (string, error) {
 	img, err := imaging.Decode(src, imaging.AutoOrientation(true))
 	if err != nil {
+		if err == ErrUnsupportedFormat {
+			return "", ErrUnsupportedFormat
+		}
 		return "", fmt.Errorf("error decoding image: %v", err)
 	}
 

cmd/backend/users.go

@@ -47,7 +47,7 @@ func (db *DB) AddUser(u *User, pass string) (int64, error) {
 	return id, nil
 }
 
-func (db *DB) GetID(userName string) (int64, bool) {
+func (db *DB) GetID(userName string) int64 {
 	var id int64
 
 	query := `
@@ -56,11 +56,11 @@ func (db *DB) GetID(userName string) (int64, bool) {
     WHERE username = ?
     `
 	row := db.QueryRow(query, userName)
-	if err := row.Scan(&id); err != nil {
+	if err := row.Scan(&id); err != nil { // seems like the only possible error is ErrNoRows
-		return 0, false
+		return 0
 	}
 
-	return id, true
+	return id
 }
 
 func (db *DB) CheckPassword(id int64, pass string) error {
@@ -146,7 +146,7 @@ func (db *DB) GetUser(id int64) (*User, error) {
 	return user, nil
 }
 
-func (db *DB) UpdateOwnAttributes(id int64, user, first, last, oldPass, newPass, newPass2 string) error {
+func (db *DB) UpdateOwnUserAttributes(id int64, user, first, last, oldPass, newPass, newPass2 string) error {
 	passwordEmpty := true
 	if len(newPass) > 0 || len(newPass2) > 0 {
 		if newPass != newPass2 {
@@ -228,7 +228,7 @@ func (db *DB) AddFirstUser(u *User, pass string) (int64, error) {
 				if err = tx.Commit(); err != nil {
 					return 0, fmt.Errorf("error committing transaction: %v", err)
 				}
-				return 2, nil
+				return -1, nil
 			}
 
 			hashedPass, err := bcrypt.GenerateFromPassword([]byte(pass), bcrypt.DefaultCost)

cmd/frontend/articles.go

@@ -87,6 +87,15 @@ func SubmitArticle(c *b.Config, db *b.DB, s *b.CookieStore) http.HandlerFunc {
 			AutoGenerated: false,
 		}
 
+		if len(article.Title) == 0 {
+			http.Error(w, "Bitte den Titel eingeben.", http.StatusBadRequest)
+			return
+		}
+		if len(article.Description) == 0 {
+			http.Error(w, "Bitte die Beschreibung eingeben.", http.StatusBadRequest)
+			return
+		}
+
 		article.ID, err = db.AddArticle(article)
 		if err != nil {
 			log.Println(err)
@@ -94,8 +103,14 @@ func SubmitArticle(c *b.Config, db *b.DB, s *b.CookieStore) http.HandlerFunc {
 			return
 		}
 
+		content := []byte(r.PostFormValue("article-content"))
+		if len(content) == 0 {
+			http.Error(w, "Bitte den Artikel eingeben.", http.StatusBadRequest)
+			return
+		}
+
 		articleAbsName := fmt.Sprint(c.ArticleDir, "/", article.ID, ".md")
-		if err = os.WriteFile(articleAbsName, []byte(r.PostFormValue("article-content")), 0644); err != nil {
+		if err = os.WriteFile(articleAbsName, content, 0644); err != nil {
 			log.Println(err)
 			http.Error(w, err.Error(), http.StatusInternalServerError)
 			return
@@ -152,8 +167,22 @@ func ResubmitArticle(c *b.Config, db *b.DB, s *b.CookieStore) http.HandlerFunc {
 		}
 
 		title := r.PostFormValue("article-title")
+		if len(title) == 0 {
+			http.Error(w, "Bitte den Titel eingeben.", http.StatusBadRequest)
+			return
+		}
+
 		description := r.PostFormValue("article-description")
+		if len(description) == 0 {
+			http.Error(w, "Bitte die Beschreibung eingeben.", http.StatusBadRequest)
+			return
+		}
+
 		content := r.PostFormValue("article-content")
+		if len(content) == 0 {
+			http.Error(w, "Bitte den Artikel eingeben.", http.StatusBadRequest)
+			return
+		}
 
 		link := fmt.Sprint(c.ArticleDir, "/", id, ".md")
 		if err = os.WriteFile(link, []byte(content), 0644); err != nil {
@@ -509,6 +538,10 @@ func UploadArticleImage(c *b.Config, s *b.CookieStore) http.HandlerFunc {
 
 		filename, err := b.SaveImage(c, file)
 		if err != nil {
+			if err == b.ErrUnsupportedFormat {
+				http.Error(w, "Das Dateiformat wird nicht unterstützt.", http.StatusBadRequest)
+				return
+			}
 			log.Println(err)
 			http.Error(w, err.Error(), http.StatusInternalServerError)
 			return

cmd/frontend/issues.go

@@ -31,21 +31,18 @@ func PublishLatestIssue(c *b.Config, db *b.DB, s *b.CookieStore) http.HandlerFun
 
 		title := r.PostFormValue("issue-title")
 		if len(title) == 0 {
-			err = fmt.Errorf("error: no title for issue specified")
+			http.Error(w, "Bitte den Titel eingeben.", http.StatusBadRequest)
-			log.Println(err)
-			http.Error(w, err.Error(), http.StatusInternalServerError)
 			return
 		}
 
 		if session.Values["issue-image"] == nil {
-			err := "error: Image required"
+			http.Error(w, "Bitte ein Bild einfügen.", http.StatusBadRequest)
-			log.Println(err)
-			http.Error(w, err, http.StatusBadRequest)
 			return
 		}
 
 		imgFileName := session.Values["issue-image"].(string)
-		imgAbsName := fmt.Sprint(c.PicsDir, "/", imgFileName)
+		fmt.Println(imgFileName)
+		imgAbsName := c.PicsDir + "/" + imgFileName
 
 		imgFile, err := os.Open(imgAbsName)
 		if err != nil {
@@ -81,8 +78,14 @@ func PublishLatestIssue(c *b.Config, db *b.DB, s *b.CookieStore) http.HandlerFun
 			return
 		}
 
+		content := []byte(r.PostFormValue("issue-content"))
+		if len(content) == 0 {
+			http.Error(w, "Bitte eine Beschreibung eingeben.", http.StatusBadRequest)
+			return
+		}
+
 		articleAbsName := fmt.Sprint(c.ArticleDir, "/", article.ID, ".md")
-		if err = os.WriteFile(articleAbsName, []byte(r.PostFormValue("article-content")), 0644); err != nil {
+		if err = os.WriteFile(articleAbsName, content, 0644); err != nil {
 			log.Println(err)
 			http.Error(w, err.Error(), http.StatusInternalServerError)
 			return
@@ -167,6 +170,10 @@ func UploadIssueImage(c *b.Config, s *b.CookieStore) http.HandlerFunc {
 
 		filename, err := b.SaveImage(c, file)
 		if err != nil {
+			if err == b.ErrUnsupportedFormat {
+				http.Error(w, "Das Dateiformat wird nicht unterstützt.", http.StatusBadRequest)
+				return
+			}
 			log.Println(err)
 			http.Error(w, err.Error(), http.StatusInternalServerError)
 			return

cmd/frontend/pdf.go

@@ -34,6 +34,24 @@ func UploadPDF(c *b.Config, s *b.CookieStore) http.HandlerFunc {
 		}
 		defer file.Close()
 
+		buffer := make([]byte, 512) // Should be enough for mime type
+		if _, err := file.Read(buffer); err != nil {
+			log.Println(err)
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+
+		if _, err := file.Seek(0, 0); err != nil {
+			log.Println(err)
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+
+		if http.DetectContentType(buffer) != "application/pdf" {
+			http.Error(w, "Die Datei ist kein PDF.", http.StatusInternalServerError)
+			return
+		}
+
 		filename := fmt.Sprint(uuid.New(), ".pdf")
 		absFilepath, err := filepath.Abs(fmt.Sprint(c.PDFDir, "/", filename))
 		if err != nil {

cmd/frontend/sessions.go

@@ -99,8 +99,8 @@ func Login(c *b.Config, db *b.DB, s *b.CookieStore) http.HandlerFunc {
 		userName := r.PostFormValue("username")
 		password := r.PostFormValue("password")
 
-		id, ok := db.GetID(userName)
+		id := db.GetID(userName)
-		if !ok {
+		if id == 0 {
 			http.Error(w, fmt.Sprintf("no such user: %v", userName), http.StatusBadRequest)
 			return
 		}

cmd/frontend/tags.go

@@ -34,7 +34,12 @@ func AddTag(c *b.Config, db *b.DB, s *b.CookieStore) http.HandlerFunc {
 			return
 		}
 
-		db.AddTag(r.PostFormValue("tag"))
+		tag := r.PostFormValue("tag")
+		if len(tag) == 0 {
+			http.Error(w, "Bitte einen Tag eingeben.", http.StatusBadRequest)
+			return
+		}
+		db.AddTag(tag)
 
 		tmpl, err := template.ParseFiles(c.WebDir + "/templates/hub.html")
 		tmpl = template.Must(tmpl, err)

cmd/frontend/users.go

@@ -10,11 +10,6 @@ import (
 	b "streifling.com/jason/cpolis/cmd/backend"
 )
 
-type UserData struct {
-	*b.User
-	Msg string
-}
-
 func checkUserStrings(user *b.User) (string, int, bool) {
 	userLen := 15
 	nameLen := 50
@@ -56,71 +51,50 @@ func AddUser(c *b.Config, db *b.DB, s *b.CookieStore) http.HandlerFunc {
 			return
 		}
 
-		role, err := strconv.Atoi(r.PostFormValue("role"))
+		user := &b.User{
+			UserName:  r.PostFormValue("username"),
+			FirstName: r.PostFormValue("first-name"),
+			LastName:  r.PostFormValue("last-name"),
+		}
+		pass := r.PostFormValue("password")
+		pass2 := r.PostFormValue("password2")
+
+		if len(user.UserName) == 0 || len(user.FirstName) == 0 ||
+			len(user.LastName) == 0 || len(pass) == 0 || len(pass2) == 0 {
+			http.Error(w, "Bitte alle Felder ausfüllen.", http.StatusBadRequest)
+			return
+		}
+
+		userString, stringLen, ok := checkUserStrings(user)
+		if !ok {
+			http.Error(w, fmt.Sprint(userString, " ist zu lang. Maximal ", stringLen, " Zeichen erlaubt."), http.StatusBadRequest)
+			return
+		}
+
+		if id := db.GetID(user.UserName); id != 0 {
+			http.Error(w, user.UserName+" ist bereits vergeben. Bitte anderen Benutzernamen wählen.", http.StatusBadRequest)
+			return
+		}
+
+		if pass != pass2 {
+			http.Error(w, "Die Passwörter stimmen nicht überein.", http.StatusBadRequest)
+			return
+		}
+
+		roleString := r.PostFormValue("role")
+		if len(roleString) == 0 {
+			http.Error(w, "Bitte eine Aufgabe vergeben.", http.StatusBadRequest)
+			return
+		}
+
+		user.Role, err = strconv.Atoi(roleString)
 		if err != nil {
 			log.Println(err)
 			http.Error(w, err.Error(), http.StatusInternalServerError)
 			return
 		}
 
-		htmlData := UserData{
+		_, err = db.AddUser(user, pass)
-			User: &b.User{
-				UserName:  r.PostFormValue("username"),
-				FirstName: r.PostFormValue("first-name"),
-				LastName:  r.PostFormValue("last-name"),
-				Role:      role,
-			},
-		}
-		pass := r.PostFormValue("password")
-		pass2 := r.PostFormValue("password2")
-
-		if len(htmlData.UserName) == 0 || len(htmlData.FirstName) == 0 ||
-			len(htmlData.LastName) == 0 || len(pass) == 0 || len(pass2) == 0 {
-			htmlData.Msg = "Alle Felder müssen ausgefüllt werden."
-			tmpl, err := template.ParseFiles(c.WebDir + "/templates/add-user.html")
-			if err = template.Must(tmpl, err).ExecuteTemplate(w, "page-content", htmlData); err != nil {
-				log.Println(err)
-				http.Error(w, err.Error(), http.StatusInternalServerError)
-				return
-			}
-			return
-		}
-		userString, stringLen, ok := checkUserStrings(htmlData.User)
-		if !ok {
-			htmlData.Msg = fmt.Sprint(userString, " ist zu lang. Maximal ",
-				stringLen, " Zeichen erlaubt.")
-			tmpl, err := template.ParseFiles(c.WebDir + "/templates/add-user.html")
-			if err = template.Must(tmpl, err).ExecuteTemplate(w, "page-content", htmlData); err != nil {
-				log.Println(err)
-				http.Error(w, err.Error(), http.StatusInternalServerError)
-				return
-			}
-			return
-		}
-		id, _ := db.GetID(htmlData.UserName)
-		if id != 0 {
-			htmlData.Msg = fmt.Sprint(htmlData.UserName,
-				" ist bereits vergeben. Bitte anderen Benutzernamen wählen.")
-			tmpl, err := template.ParseFiles(c.WebDir + "/templates/add-user.html")
-			if err = template.Must(tmpl, err).ExecuteTemplate(w, "page-content", htmlData); err != nil {
-				log.Println(err)
-				http.Error(w, err.Error(), http.StatusInternalServerError)
-				return
-			}
-			return
-		}
-		if pass != pass2 {
-			htmlData.Msg = "Die Passwörter stimmen nicht überein."
-			tmpl, err := template.ParseFiles(c.WebDir + "/templates/add-user.html")
-			if err = template.Must(tmpl, err).ExecuteTemplate(w, "page-content", htmlData); err != nil {
-				log.Println(err)
-				http.Error(w, err.Error(), http.StatusInternalServerError)
-				return
-			}
-			return
-		}
-
-		_, err = db.AddUser(htmlData.User, pass)
 		if err != nil {
 			log.Println(err)
 			http.Error(w, err.Error(), http.StatusInternalServerError)
@@ -171,75 +145,42 @@ func UpdateSelf(c *b.Config, db *b.DB, s *b.CookieStore) http.HandlerFunc {
 			return
 		}
 
-		userData := UserData{
+		user := &b.User{
-			User: &b.User{
+			ID:        session.Values["id"].(int64),
-				ID:        session.Values["id"].(int64),
+			UserName:  r.PostFormValue("username"),
-				UserName:  r.PostFormValue("username"),
+			FirstName: r.PostFormValue("first-name"),
-				FirstName: r.PostFormValue("first-name"),
+			LastName:  r.PostFormValue("last-name"),
-				LastName:  r.PostFormValue("last-name"),
-			},
 		}
+
 		oldPass := r.PostFormValue("old-password")
 		newPass := r.PostFormValue("password")
 		newPass2 := r.PostFormValue("password2")
 
-		if len(userData.UserName) == 0 || len(userData.FirstName) == 0 ||
+		if len(user.UserName) == 0 {
-			len(userData.LastName) == 0 {
+			http.Error(w, "Bitte den Benutzernamen ausfüllen.", http.StatusBadRequest)
-			userData.Msg = "Alle Felder mit * müssen ausgefüllt sein."
-			tmpl, err := template.ParseFiles(c.WebDir + "/templates/edit-user.html")
-			tmpl = template.Must(tmpl, err)
-			if err = tmpl.ExecuteTemplate(w, "page-content", userData.Msg); err != nil {
-				log.Println(err)
-				http.Error(w, err.Error(), http.StatusInternalServerError)
-				return
-			}
 			return
 		}
 
-		userString, stringLen, ok := checkUserStrings(userData.User)
+		if len(user.FirstName) == 0 || len(user.LastName) == 0 {
+			http.Error(w, "Bitte den vollständigen Namen ausfüllen.", http.StatusBadRequest)
+			return
+		}
+
+		userString, stringLen, ok := checkUserStrings(user)
 		if !ok {
-			userData.Msg = fmt.Sprint(userString, " ist zu lang. Maximal ",
+			http.Error(w, fmt.Sprint(userString, " ist zu lang. Maximal ", stringLen, " Zeichen erlaubt."), http.StatusBadRequest)
-				stringLen, " Zeichen erlaubt.")
-			tmpl, err := template.ParseFiles(c.WebDir + "/templates/edit-user.html")
-			tmpl = template.Must(tmpl, err)
-			if err = tmpl.ExecuteTemplate(w, "page-content", userData); err != nil {
-				log.Println(err)
-				http.Error(w, err.Error(), http.StatusInternalServerError)
-				return
-			}
 			return
 		}
 
-		if id, ok := db.GetID(userData.UserName); ok {
+		if id := db.GetID(user.UserName); id != 0 && id != user.ID {
-			if id != userData.ID {
+			http.Error(w, user.UserName+" ist bereits vergeben. Bitte anderen Benutzernamen wählen.", http.StatusBadRequest)
-				userData.Msg = "Benutzername bereits vergeben."
+			return
-				userData.UserName = ""
-				tmpl, err := template.ParseFiles(c.WebDir + "/templates/edit-user.html")
-				tmpl = template.Must(tmpl, err)
-				if err = tmpl.ExecuteTemplate(w, "page-content", userData); err != nil {
-					log.Println(err)
-					http.Error(w, err.Error(), http.StatusInternalServerError)
-					return
-				}
-				return
-			}
 		}
 
-		if err = db.UpdateOwnAttributes(
+		if err = db.UpdateOwnUserAttributes(user.ID, user.UserName, user.FirstName, user.LastName, oldPass, newPass, newPass2); err != nil {
-			userData.ID,
+			log.Println("error: user:", user.ID, err)
-			userData.UserName,
+			http.Error(w, "Benutzerdaten konnten nicht aktualisiert werden.", http.StatusInternalServerError)
-			userData.FirstName,
+			return
-			userData.LastName,
-			oldPass,
-			newPass,
-			newPass2); err != nil {
-			userData.Msg = "Aktualisierung der Benutzerdaten fehlgeschlagen."
-			tmpl, err := template.ParseFiles(c.WebDir + "/templates/edit-user.html")
-			if err = template.Must(tmpl, err).ExecuteTemplate(w, "page-content", userData); err != nil {
-				log.Println(err)
-				http.Error(w, err.Error(), http.StatusInternalServerError)
-				return
-			}
 		}
 
 		tmpl, err := template.ParseFiles(c.WebDir + "/templates/hub.html")
@@ -255,77 +196,44 @@ func UpdateSelf(c *b.Config, db *b.DB, s *b.CookieStore) http.HandlerFunc {
 func AddFirstUser(c *b.Config, db *b.DB, s *b.CookieStore) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
 		var err error
-		htmlData := UserData{
+		user := &b.User{
-			User: &b.User{
+			UserName:  r.PostFormValue("username"),
-				UserName:  r.PostFormValue("username"),
+			FirstName: r.PostFormValue("first-name"),
-				FirstName: r.PostFormValue("first-name"),
+			LastName:  r.PostFormValue("last-name"),
-				LastName:  r.PostFormValue("last-name"),
+			Role:      b.Admin,
-				Role:      b.Admin,
-			},
 		}
 		pass := r.PostFormValue("password")
 		pass2 := r.PostFormValue("password2")
 
-		if len(htmlData.UserName) == 0 || len(htmlData.FirstName) == 0 ||
+		if len(user.UserName) == 0 || len(user.FirstName) == 0 ||
-			len(htmlData.LastName) == 0 || len(pass) == 0 || len(pass2) == 0 {
+			len(user.LastName) == 0 || len(pass) == 0 || len(pass2) == 0 {
-			htmlData.Msg = "Alle Felder müssen ausgefüllt werden."
+			http.Error(w, "Bitte alle Felder ausfüllen.", http.StatusBadRequest)
-			tmpl, err := template.ParseFiles(c.WebDir + "/templates/add-user.html")
-			if err = template.Must(tmpl, err).ExecuteTemplate(w, "page-content", htmlData); err != nil {
-				log.Println(err)
-				http.Error(w, err.Error(), http.StatusInternalServerError)
-				return
-			}
-			return
-		}
-		userString, stringLen, ok := checkUserStrings(htmlData.User)
-		if !ok {
-			htmlData.Msg = fmt.Sprint(userString, " ist zu lang. Maximal ",
-				stringLen, " Zeichen erlaubt.")
-			tmpl, err := template.ParseFiles(c.WebDir + "/templates/add-user.html")
-			if err = template.Must(tmpl, err).ExecuteTemplate(w, "page-content", htmlData); err != nil {
-				log.Println(err)
-				http.Error(w, err.Error(), http.StatusInternalServerError)
-				return
-			}
-			return
-		}
-		id, _ := db.GetID(htmlData.UserName)
-		if id != 0 {
-			htmlData.Msg = fmt.Sprint(htmlData.UserName,
-				" ist bereits vergeben. Bitte anderen Benutzernamen wählen.")
-			tmpl, err := template.ParseFiles(c.WebDir + "/templates/add-user.html")
-			if err = template.Must(tmpl, err).ExecuteTemplate(w, "page-content", htmlData); err != nil {
-				log.Println(err)
-				http.Error(w, err.Error(), http.StatusInternalServerError)
-				return
-			}
-			return
-		}
-		if pass != pass2 {
-			htmlData.Msg = "Die Passwörter stimmen nicht überein."
-			tmpl, err := template.ParseFiles(c.WebDir + "/templates/add-user.html")
-			if err = template.Must(tmpl, err).ExecuteTemplate(w, "page-content", htmlData); err != nil {
-				log.Println(err)
-				http.Error(w, err.Error(), http.StatusInternalServerError)
-				return
-			}
 			return
 		}
 
-		htmlData.ID, err = db.AddFirstUser(htmlData.User, pass)
+		userString, stringLen, ok := checkUserStrings(user)
+		if !ok {
+			http.Error(w, fmt.Sprint(userString, " ist zu lang. Maximal ", stringLen, " Zeichen erlaubt."), http.StatusBadRequest)
+			return
+		}
+
+		if pass != pass2 {
+			http.Error(w, "Die Passwörter stimmen nicht überein.", http.StatusBadRequest)
+			return
+		}
+
+		user.ID, err = db.AddFirstUser(user, pass)
 		if err != nil {
 			log.Println(err)
 			http.Error(w, err.Error(), http.StatusInternalServerError)
 			return
 		}
-		if htmlData.ID > 1 {
+		if user.ID == -1 {
-			errString := "error: there is already a first user"
+			http.Error(w, "Bitte ein Benutzerkonto von einem Administrator anlegen lassen.", http.StatusInternalServerError)
-			log.Println(errString)
-			http.Error(w, errString, http.StatusInternalServerError)
 			return
 		}
 
-		if err := saveSession(w, r, s, htmlData.User); err != nil {
+		if err := saveSession(w, r, s, user); err != nil {
 			log.Println(err)
 			http.Error(w, err.Error(), http.StatusInternalServerError)
 			return
@@ -418,93 +326,55 @@ func UpdateUser(c *b.Config, db *b.DB, s *b.CookieStore) http.HandlerFunc {
 			return
 		}
 
-		id, err := strconv.ParseInt(r.PathValue("id"), 10, 64)
+		user := new(b.User)
+		user.ID, err = strconv.ParseInt(r.PathValue("id"), 10, 64)
 		if err != nil {
 			log.Println(err)
 			http.Error(w, err.Error(), http.StatusInternalServerError)
 			return
 		}
 
-		role, err := strconv.Atoi(r.PostFormValue("role"))
+		user.Role, err = strconv.Atoi(r.PostFormValue("role"))
 		if err != nil {
 			log.Println(err)
 			http.Error(w, err.Error(), http.StatusInternalServerError)
 			return
 		}
 
-		userData := UserData{
+		user.UserName = r.PostFormValue("username")
-			User: &b.User{
+		if len(user.UserName) == 0 {
-				ID:        id,
+			http.Error(w, "Bitte den Benutzernamen ausfüllen.", http.StatusInternalServerError)
-				UserName:  r.PostFormValue("username"),
+			return
-				FirstName: r.PostFormValue("first-name"),
-				LastName:  r.PostFormValue("last-name"),
-				Role:      role,
-			},
 		}
+
+		user.FirstName = r.PostFormValue("first-name")
+		user.LastName = r.PostFormValue("last-name")
+		if len(user.FirstName) == 0 || len(user.LastName) == 0 {
+			http.Error(w, "Bitte den vollständigen Namen ausfüllen.", http.StatusInternalServerError)
+			return
+		}
+
 		newPass := r.PostFormValue("password")
 		newPass2 := r.PostFormValue("password2")
 
-		if len(userData.UserName) == 0 || len(userData.FirstName) == 0 ||
+		userString, stringLen, ok := checkUserStrings(user)
-			len(userData.LastName) == 0 {
-			userData.Msg = "Alle Felder mit * müssen ausgefüllt sein."
-			tmpl, err := template.ParseFiles(c.WebDir + "/templates/edit-user.html")
-			tmpl = template.Must(tmpl, err)
-			if err = tmpl.ExecuteTemplate(w, "page-content", userData.Msg); err != nil {
-				log.Println(err)
-				http.Error(w, err.Error(), http.StatusInternalServerError)
-				return
-			}
-			return
-		}
-
-		userString, stringLen, ok := checkUserStrings(userData.User)
 		if !ok {
-			userData.Msg = fmt.Sprint(userString, " ist zu lang. Maximal ",
+			http.Error(w, fmt.Sprint(userString, " ist zu lang. Maximal ", stringLen, " Zeichen erlaubt."), http.StatusBadRequest)
-				stringLen, " Zeichen erlaubt.")
-			tmpl, err := template.ParseFiles(c.WebDir + "/templates/edit-user.html")
-			tmpl = template.Must(tmpl, err)
-			if err = tmpl.ExecuteTemplate(w, "page-content", userData); err != nil {
-				log.Println(err)
-				http.Error(w, err.Error(), http.StatusInternalServerError)
-				return
-			}
 			return
 		}
 
-		if id, ok := db.GetID(userData.UserName); ok {
+		if id := db.GetID(user.UserName); id != 0 && id != user.ID {
-			if id != userData.ID {
+			http.Error(w, user.UserName+" ist bereits vergeben. Bitte anderen Benutzernamen wählen.", http.StatusBadRequest)
-				userData.Msg = "Benutzername bereits vergeben."
+			return
-				userData.UserName = ""
-				tmpl, err := template.ParseFiles(c.WebDir + "/templates/edit-user.html")
-				tmpl = template.Must(tmpl, err)
-				if err = tmpl.ExecuteTemplate(w, "page-content", userData); err != nil {
-					log.Println(err)
-					http.Error(w, err.Error(), http.StatusInternalServerError)
-					return
-				}
-				return
-			}
 		}
 
-		if err = db.UpdateUserAttributes(
+		if err = db.UpdateUserAttributes(user.ID, user.UserName, user.FirstName, user.LastName, newPass, newPass2, user.Role); err != nil {
-			userData.ID,
+			log.Println("error: user:", user.ID, err)
-			userData.UserName,
+			http.Error(w, "Benutzerdaten konnten nicht aktualisiert werden.", http.StatusInternalServerError)
-			userData.FirstName,
+			return
-			userData.LastName,
-			newPass,
-			newPass2,
-			userData.Role); err != nil {
-			userData.Msg = "Aktualisierung der Benutzerdaten fehlgeschlagen."
-			tmpl, err := template.ParseFiles(c.WebDir + "/templates/edit-user.html")
-			if err = template.Must(tmpl, err).ExecuteTemplate(w, "page-content", userData); err != nil {
-				log.Println(err)
-				http.Error(w, err.Error(), http.StatusInternalServerError)
-				return
-			}
 		}
 
-		tmpl, err := template.ParseFiles(c.WebDir + "/templates/hub.html")
+		tmpl := template.Must(template.ParseFiles(c.WebDir + "/templates/hub.html"))
-		tmpl = template.Must(tmpl, err)
 		if err = tmpl.ExecuteTemplate(w, "page-content", session.Values["role"].(int)); err != nil {
 			log.Println(err)
 			http.Error(w, err.Error(), http.StatusInternalServerError)

web/templates/add-user.html

@@ -49,11 +49,4 @@
         <button class="btn" hx-get="/hub" hx-target="#page-content">Abbrechen</button>
     </div>
 </form>
-
-<script>
-    var msg = "{{.Msg}}";
-    if (msg != "") {
-        alert(msg);
-    }
-</script>
 {{end}}

web/templates/editor.html

@@ -64,6 +64,7 @@
                     onSuccess(data);
                 })
                 .catch(error => {
+                    htmx.trigger(htmx.find('#notification'), 'htmx:responseError', {xhr: {responseText: error.message}});
                     onError(error);
                 });
         },

web/templates/first-user.html

@@ -29,11 +29,4 @@
         <input class="action-btn" type="submit" value="Anlegen" hx-post="/user/add-first" hx-target="#page-content" />
     </div>
 </form>
-
-<script>
-    var msg = "{{.Msg}}";
-    if (msg != "") {
-        alert(msg);
-    }
-</script>
 {{end}}

web/templates/index.html

@@ -28,6 +28,10 @@
     </header>
 
     <main class="mx-4">
+        <div class="hidden bg-slate-950 dark:bg-slate-50 fixed font-bold p-4 right-8 rounded-lg shadow-lg text-slate-100 dark:text-slate-900 top-8 z-50"
+            id="notification">
+        </div>
+
         <div id="page-content">
             {{template "page-content" .}}
         </div>
@@ -35,7 +39,7 @@
 
     <footer class="text-center text-gray-500 my-8">
         <p>&copy; 2024 Jason Streifling. Alle Rechte vorbehalten.</p>
-        <p>v0.11.1 - <strong>Alpha: Drastische Änderungen und Fehler vorbehalten.</strong></p>
+        <p>v0.12.0 - <strong>Alpha: Drastische Änderungen und Fehler vorbehalten.</strong></p>
     </footer>
 
     <script src="https://unpkg.com/htmx.org@2.0.2"></script>
@@ -66,6 +70,16 @@
             });
         });
     </script>
+    <script>
+        htmx.on('htmx:responseError', function (event) {
+            var notification = document.getElementById('notification');
+            notification.innerText = event.detail.xhr.responseText;
+            notification.classList.remove('hidden');
+            setTimeout(function () {
+                notification.classList.add('hidden');
+            }, 5000);
+        });
+    </script>
 </body>
 
 </html>