replace stub returns with redirects

app/routes/users.py

@@ -269,14 +269,17 @@ def settings_form(username):
 def set_avatar(username):
     user = get_active_user()
     if user.is_guest():
-        return 'no'
+        flash('You must be logged in to perform this action.', InfoboxKind.ERROR)
+        return redirect(url_for('.settings', user.username))
     if 'avatar' not in request.files:
-        return 'no!...'
+        flash('Avatar missing.', InfoboxKind.ERROR)
+        return redirect(url_for('.settings', user.username))
 
     file = request.files['avatar']
 
     if file.filename == '':
-        return 'no..?'
+        flash('Avatar missing.', InfoboxKind.ERROR)
+        return redirect(url_for('.settings', user.username))
 
     file_bytes = file.read()
 
@@ -300,7 +303,8 @@ def set_avatar(username):
             old_avatar.delete()
         return redirect(url_for('.settings', username=user.username))
     else:
-        return 'uhhhh no'
+        flash('Something went wrong. Please try again later.', InfoboxKind.WARN)
+        return redirect(url_for('.settings', user.username))
 
 
 @bp.post('/<username>/clear_avatar')
@@ -308,7 +312,7 @@ def set_avatar(username):
 def clear_avatar(username):
     user = get_active_user()
     if user.is_default_avatar():
-        return 'no'
+        return redirect(url_for('.settings', user.username))
 
     old_avatar = Avatars.find({'id': user.avatar_id})
     user.update({'avatar_id': 1})
@@ -336,9 +340,9 @@ def log_out():
 def confirm_user(user_id):
     target_user = Users.find({"id": user_id})
     if not target_user:
-        return "no"
+        return redirect(url_for('.all_topics'))
     if int(target_user.permission) > PermissionLevel.GUEST.value:
-        return "no"
+        return redirect(url_for('.page', username=target_user.username))
 
     target_user.update({
         "permission": PermissionLevel.USER.value,
@@ -353,9 +357,9 @@ def confirm_user(user_id):
 def mod_user(user_id):
     target_user = Users.find({"id": user_id})
     if not target_user:
-        return "no"
+        return redirect(url_for('.all_topics'))
     if target_user.is_mod():
-        return "no"
+        return redirect(url_for('.page', username=target_user.username))
 
     target_user.update({
         "permission": PermissionLevel.MODERATOR.value,
@@ -369,9 +373,9 @@ def mod_user(user_id):
 def demod_user(user_id):
     target_user = Users.find({"id": user_id})
     if not target_user:
-        return "no"
+        return redirect(url_for('.all_topics'))
     if not target_user.is_mod():
-        return "no"
+        return redirect(url_for('.page', username=target_user.username))
 
     target_user.update({
         "permission": PermissionLevel.USER.value,
@@ -385,9 +389,9 @@ def demod_user(user_id):
 def guest_user(user_id):
     target_user = Users.find({"id": user_id})
     if not target_user:
-        return "no"
+        return redirect(url_for('.all_topics'))
     if target_user.is_mod():
-        return "no"
+        return redirect(url_for('.page', username=target_user.username))
 
     target_user.update({
         "permission": PermissionLevel.GUEST.value,