I am new to coding and I have just written an app using Flask and Socket.io called Chatbox.
Here is the app: Github: Chatbox-2020
It runs smoothly on local, however, when I pushed it to Heroku, it keeps showing errors:
2020-05-26T11:01:02.401356+00:00 app[web.1]: [2020-05-26 11:01:02 +0000] [4] [INFO] Listening at: http://0.0.0.0:34980 (4)
2020-05-26T11:01:02.401471+00:00 app[web.1]: [2020-05-26 11:01:02 +0000] [4] [INFO] Using worker: sync
2020-05-26T11:01:02.406378+00:00 app[web.1]: [2020-05-26 11:01:02 +0000] [9] [INFO] Booting worker with pid: 9
2020-05-26T11:01:02.488374+00:00 app[web.1]: [2020-05-26 11:01:02 +0000] [10] [INFO] Booting worker with pid: 10
2020-05-26T11:01:03.881191+00:00 heroku[web.1]: State changed from starting to up
2020-05-26T11:01:03.868598+00:00 app[web.1]: PRINT INFO: CHANNEL
2020-05-26T11:01:03.868668+00:00 app[web.1]: NAME: General
2020-05-26T11:01:03.868719+00:00 app[web.1]: CREATOR: default
2020-05-26T11:01:03.868779+00:00 app[web.1]: MESSAGES: 0
2020-05-26T11:01:03.868830+00:00 app[web.1]: DEFAULT CHANNEL CREATED
2020-05-26T11:01:03.870458+00:00 app[web.1]: Failed to parse '' as an attribute name or function call.
2020-05-26T11:01:03.870490+00:00 app[web.1]: PRINT INFO: CHANNEL
2020-05-26T11:01:03.870495+00:00 app[web.1]: NAME: General
2020-05-26T11:01:03.870522+00:00 app[web.1]: CREATOR: default
2020-05-26T11:01:03.870527+00:00 app[web.1]: MESSAGES: 0
2020-05-26T11:01:03.870548+00:00 app[web.1]: DEFAULT CHANNEL CREATED
2020-05-26T11:01:03.870894+00:00 app[web.1]: [2020-05-26 11:01:03 +0000] [10] [INFO] Worker exiting (pid: 10)
2020-05-26T11:01:03.872098+00:00 app[web.1]: Failed to parse '' as an attribute name or function call.
2020-05-26T11:01:03.872376+00:00 app[web.1]: [2020-05-26 11:01:03 +0000] [9] [INFO] Worker exiting (pid: 9)
2020-05-26T11:01:04.036138+00:00 app[web.1]: [2020-05-26 11:01:04 +0000] [4] [INFO] Shutting down: Master
2020-05-26T11:01:04.036243+00:00 app[web.1]: [2020-05-26 11:01:04 +0000] [4] [INFO] Reason: App failed to load.
2020-05-26T11:01:04.117169+00:00 heroku[web.1]: Process exited with status 4
2020-05-26T11:01:04.160505+00:00 heroku[web.1]: State changed from up to crashed
The error that keeps showing is "Failed to parse '' as an attribute name or function call." What exactly does it mean? Grateful if someone could help me figure out the problem!