Do not throw error messages at users, let the frontend handle errors

fixes #1

ajax.go

@@ -24,10 +24,7 @@ func (a ajaxResponse) Bytes() []byte {
 
 func ajaxGetHandler(res http.ResponseWriter, r *http.Request, session *sessions.Session, ctx *pongo2.Context) (*string, error) {
 	res.Header().Set("Content-Type", "application/json")
-	user, err := checkLogin(r, session)
+	user, _ := checkLogin(r, session)
-	if err != nil {
-		return nil, err // TODO: Handle in-app?
-	}
 
 	if user == nil || !storage.IsPresent(user.UserFile) {
 		res.Write(ajaxResponse{Error: true}.Bytes())
@@ -36,13 +33,12 @@ func ajaxGetHandler(res http.ResponseWriter, r *http.Request, session *sessions.
 
 	userFileRaw, err := storage.Read(user.UserFile)
 	if err != nil {
-		return nil, err // TODO: Handle in-app?
+		fmt.Printf("ERR: Unable to read user file: %s\n", err)
+		res.Write(ajaxResponse{Error: true}.Bytes())
+		return nil, nil
 	}
 
-	userFile, err := readDataObject(userFileRaw)
+	userFile, _ := readDataObject(userFileRaw)
-	if err != nil {
-		return nil, err // TODO: Handle in-app?
-	}
 
 	res.Write(ajaxResponse{Version: userFile.MetaData.Version, Data: userFile.Data}.Bytes())
 	return nil, nil
@@ -50,10 +46,7 @@ func ajaxGetHandler(res http.ResponseWriter, r *http.Request, session *sessions.
 
 func ajaxPostHandler(res http.ResponseWriter, r *http.Request, session *sessions.Session, ctx *pongo2.Context) (*string, error) {
 	res.Header().Set("Content-Type", "application/json")
-	user, err := checkLogin(r, session)
+	user, _ := checkLogin(r, session)
-	if err != nil {
-		return nil, err // TODO: Handle in-app?
-	}
 
 	if user == nil {
 		res.Write(ajaxResponse{Error: true, Type: "login"}.Bytes())
@@ -67,13 +60,12 @@ func ajaxPostHandler(res http.ResponseWriter, r *http.Request, session *sessions
 
 	userFileRaw, err := storage.Read(user.UserFile)
 	if err != nil {
-		return nil, err // TODO: Handle in-app?
+		fmt.Printf("ERR: Unable to read user file: %s\n", err)
+		res.Write(ajaxResponse{Error: true, Type: "storage_error"}.Bytes())
+		return nil, nil
 	}
 
-	userFile, err := readDataObject(userFileRaw)
+	userFile, _ := readDataObject(userFileRaw)
-	if err != nil {
-		return nil, err // TODO: Handle in-app?
-	}
 
 	var (
 		version  = r.FormValue("version")
@@ -92,19 +84,20 @@ func ajaxPostHandler(res http.ResponseWriter, r *http.Request, session *sessions
 	}
 
 	if err := storage.Backup(user.UserFile); err != nil {
-		return nil, err // TODO: Handle in-app?
+		fmt.Printf("ERR: Unable to backup user file: %s\n", err)
+		res.Write(ajaxResponse{Error: true, Type: "storage_error"}.Bytes())
+		return nil, nil
 	}
 
 	userFile.MetaData.Version = checksum
 	userFile.Data = data
 
-	d, err := userFile.GetData()
+	d, _ := userFile.GetData()
-	if err != nil {
-		return nil, err // TODO: Handle in-app?
-	}
 
 	if err := storage.Write(user.UserFile, d); err != nil {
-		return nil, err // TODO: Handle in-app?
+		fmt.Printf("ERR: Unable to write user file: %s\n", err)
+		res.Write(ajaxResponse{Error: true, Type: "storage_error"}.Bytes())
+		return nil, nil
 	}
 
 	res.Write(ajaxResponse{Version: userFile.MetaData.Version, Data: userFile.Data}.Bytes())

login.go

@@ -24,13 +24,12 @@ func loginHandler(res http.ResponseWriter, r *http.Request, session *sessions.Se
 
 	userFileRaw, err := storage.Read(createUserFilename(username))
 	if err != nil {
-		return nil, err // TODO: Handle in-app?
+		fmt.Printf("ERR: Unable to read user file: %s\n", err)
+		(*ctx)["error"] = true
+		return stringPointer("login.html"), nil
 	}
 
-	userFile, err := readDataObject(userFileRaw)
+	userFile, _ := readDataObject(userFileRaw)
-	if err != nil {
-		return nil, err // TODO: Handle in-app?
-	}
 
 	if userFile.MetaData.Password != password {
 		(*ctx)["error"] = true
@@ -74,7 +73,7 @@ func checkLogin(r *http.Request, session *sessions.Session) (*authorizedAccount,
 	vars := mux.Vars(r)
 	idx, err := strconv.ParseInt(vars["userIndex"], 10, 64)
 	if err != nil {
-		return nil, err // TODO: Handle in-app?
+		return nil, err
 	}
 
 	auth, ok := session.Values["authorizedAccounts"].(authorizedAccounts)

overview.go

@@ -8,10 +8,7 @@ import (
 )
 
 func overviewHandler(res http.ResponseWriter, r *http.Request, session *sessions.Session, ctx *pongo2.Context) (*string, error) {
-	user, err := checkLogin(r, session)
+	user, _ := checkLogin(r, session)
-	if err != nil {
-		return nil, err // TODO: Handle in-app?
-	}
 
 	if user == nil || !storage.IsPresent(user.UserFile) {
 		http.Redirect(res, r, "../../login", http.StatusFound)

register.go

@@ -28,15 +28,14 @@ func registerHandler(res http.ResponseWriter, r *http.Request, session *sessions
 
 	d := dataObject{}
 	d.MetaData.Password = hashedPassword
-	data, err := d.GetData()
+	data, _ := d.GetData()
-	if err != nil {
-		return nil, err // TODO: Handle in-app?
-	}
 
-	if err := storage.Write(createUserFilename(username), data); err == nil {
+	if err := storage.Write(createUserFilename(username), data); err != nil {
-		(*ctx)["created"] = true
+		fmt.Printf("ERR: Unable to write user file: %s\n", err)
+		(*ctx)["error"] = true
 		return stringPointer("register.html"), nil
 	}
 
-	return nil, err // TODO: Handle in-app?
+	(*ctx)["created"] = true
+	return stringPointer("register.html"), nil
 }

templates/register.html

@@ -18,6 +18,14 @@
   </div>
 </div>
 {% endif %}
+{% if error %}
+<div class="row">
+  <div class="col-md-4 col-md-push-4 alert alert-danger fade in">
+    <h4>Ooops&hellip;</h4>
+    <p>Something went wrong. Please try again.</p>
+  </div>
+</div>
+{% endif %}
 <form class="form-signin" method="post">
   <h2 class="form-signin-heading">Please register</h2>
   <input type="text" name="username" class="form-control" placeholder="Username">