check if counter exists before incrementing

nonexistant counter prints warning + recommends running refresh-counters

tlapbot/owncast_helpers.py

@@ -133,7 +133,26 @@ def change_display_name(db, user_id, new_name):
         current_app.logger.error("To user:", user_id, new_name)
 
 
+def check_counter_exists(db, counter_name):
+    try:
+        cursor = db.execute(
+            "SELECT counter FROM counters WHERE name = ?",
+            (counter_name,)
+        )
+        counter = cursor.fetchone()
+        if counter is None:
+            current_app.logger.warning("Counter not found in database.")
+            current_app.logger.warning("Maybe you forgot to run the refresh-counters CLI command "
+                                       "after you added a new counter to the config?")
+            return False
+        return True
+    except Error as e:
+        current_app.logger.error("Error occured checking if counter exists:", e.args[0])
+        current_app.logger.error("For counter:", counter_name)
+
+
 def add_to_counter(db, counter_name):
+    if check_counter_exists(db, counter_name):
         try:
             cursor = db.execute(
                 "UPDATE counters SET count = count + 1 WHERE name = ?",