Rasa error disappears after deleting database conversations Why? - rasa-nlu

Question

I have a strange problem in Rasa. When I deleted some action name or changed some action name. At the same time, I also deleted some slots. Rasa will get the following error:
2019-10-12 13:57:58 ERROR rasa.core.trackers - Tried to set non existent slot 'mathcalc'. Make sure you added all your slots to your domain file.
2019-10-12 13:57:58 ERROR rasa.core.trackers - Tried to set non existent slot 'mathcalc'. Make sure you added all your slots to your domain file.
2019-10-12 13:57:58 ERROR rasa.core.trackers - Tried to set non existent slot 'mathcalc'. Make sure you added all your slots to your domain file.
2019-10-12 13:57:58 ERROR rasa.core.trackers - Tried to set non existent slot 'mathcalc'. Make sure you added all your slots to your domain file.
2019-10-12 13:57:58 ERROR rasa.core.trackers - Tried to set non existent slot 'mathcalc'. Make sure you added all your slots to your domain file.
2019-10-12 13:57:58 WARNING rasa.core.featurizers - Feature 'intent_calc_plus' could not be found in feature map.
2019-10-12 13:57:58 WARNING rasa.core.featurizers - Feature 'active_form_meeting_form' could not be found in feature map.
2019-10-12 13:57:58 WARNING rasa.core.featurizers - Feature 'entity_mathcalc' could not be found in feature map.
2019-10-12 13:57:58 WARNING rasa.core.featurizers - Feature 'intent_calc_plus' could not be found in feature map.
2019-10-12 13:57:58 WARNING rasa.core.featurizers - Feature 'active_form_meeting_form' could not be found in feature map.
2019-10-12 13:57:58 WARNING rasa.core.featurizers - Feature 'entity_mathcalc' could not be found in feature map.
2019-10-12 13:57:58 WARNING rasa.core.featurizers - Feature 'intent_calc_plus' could not be found in feature map.
2019-10-13 09:08:21 WARNING rasa.core.domain - Failed to use action 'action_calc_plus' in history. Please make sure all actions are listed in the domains action list. If you recently removed an action, don't worry about this warning. It should stop appearing after a while.
2019-10-13 09:08:21 WARNING rasa.core.domain - Failed to use action 'action_calc_minus' in history. Please make sure all actions are listed in the domains action list. If you recently removed an action, don't worry about this warning. It should stop appearing after a while.
2019-10-13 09:08:21 WARNING rasa.core.domain - Failed to use action 'action_calc_divide' in history. Please make sure all actions are listed in the domains action list. If you recently removed an action, don't worry about this warning. It should stop appearing after a while.
2019-10-13 09:08:21 WARNING rasa.core.domain - Failed to use action 'action_calc_multiply' in history. Please make sure all actions are listed in the domains action list. If you recently removed an action, don't worry about this warning. It should stop appearing after a while.
2019-10-13 09:08:21 WARNING rasa.core.domain - Failed to use action 'action_calc_multiply' in history. Please make sure all actions are listed in the domains action list. If you recently removed an action, don't worry about this warning. It should stop appearing after a while.
The slot 'mathcalc' and Feature 'intent_calc_plus' and action 'action_calc_plus' that I have deleted.
The above error disappears only when I delete the conversations table. What is the reason?
I can't delete the conversations table in the production environment.
Thanks a lot!

Answer 1

Looks like I'm a bit late at answering but here it is.
You are getting that error because when the user re-initiates the conversation with the bot, rasa first retrieves the conversation it had before with the user (called a tracker). This means that in the previous conversation, it had the slot mathcalc. But this time when it tries to populate the slot mathcalc, it can't because it doesn't exist this time. This is the reason that you're getting the error.
Here is what a tracker looks like:
{
"sender_id": "2408196042602645",
"slots": {
"mathcalc": null,
...
},
"latest_message": {...},
"events": [...]
}
To solve the problem, you should re-train your bot with the new data and it should be fine.
The reason that this problem disappears when you delete the conversations table is because the previous conversation doesn't exist and so it doesn't try to re-create the last conversation.
Hope that helps.