How to use callback Rasa 3.x

Rasa Open Source
1

Hello, I decided to make this post because I followed the instructions provided in the documentation but I can’t simulate a POST to the callback channel using Postman. I’ve made a Scheduled_reminder script and I want it to POST to the callback channel to trigger an external response. I have set up the appropriate Intents, Entities, Slots and rules as per the Plant example in the documentation. I also followed the instructions and added:

callback:
  # URL to which Core will send the bot responses
  url: "http://localhost:5034/bot"

to the credentials.yml file and trained the model to include them. What I when trying again after using “rasa run” and sending the POST from Postman is the following: Postman:

Screenshot 2022-08-26 at 8.16.29 PM
Screenshot 2022-08-26 at 8.16.29 PM2094×1420 263 KB

Terminal:

[2022-08-26 20:16:15 +0300] [38931] [ERROR] Exception occurred while handling uri: 'http://0.0.0.0:5005/webhooks/callback/webhook'
Traceback (most recent call last):
  File "/opt/miniconda3/envs/rasa_project/lib/python3.7/site-packages/rasa/engine/graph.py", line 464, in __call__
    output = self._fn(self._component, **run_kwargs)
  File "/opt/miniconda3/envs/rasa_project/lib/python3.7/site-packages/rasa/nlu/classifiers/regex_message_handler.py", line 55, in process
    for message in messages
  File "/opt/miniconda3/envs/rasa_project/lib/python3.7/site-packages/rasa/nlu/classifiers/regex_message_handler.py", line 55, in <listcomp>
    for message in messages
  File "/opt/miniconda3/envs/rasa_project/lib/python3.7/site-packages/rasa/shared/core/training_data/story_reader/yaml_story_reader.py", line 618, in unpack_regex_message
    user_text = message.get(TEXT).strip()
AttributeError: 'NoneType' object has no attribute 'strip'

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "handle_request", line 83, in handle_request
    )
  File "/opt/miniconda3/envs/rasa_project/lib/python3.7/site-packages/rasa/core/channels/callback.py", line 77, in webhook
    UserMessage(text, collector, sender_id, input_channel=self.name())
  File "/opt/miniconda3/envs/rasa_project/lib/python3.7/site-packages/rasa/core/channels/channel.py", line 89, in handler
    await app.ctx.agent.handle_message(message)
  File "/opt/miniconda3/envs/rasa_project/lib/python3.7/site-packages/rasa/core/agent.py", line 421, in handle_message
    message
  File "/opt/miniconda3/envs/rasa_project/lib/python3.7/site-packages/rasa/core/processor.py", line 137, in handle_message
    tracker = await self.log_message(message, should_save_tracker=False)
  File "/opt/miniconda3/envs/rasa_project/lib/python3.7/site-packages/rasa/core/processor.py", line 384, in log_message
    await self._handle_message_with_tracker(message, tracker)
  File "/opt/miniconda3/envs/rasa_project/lib/python3.7/site-packages/rasa/core/processor.py", line 683, in _handle_message_with_tracker
    parse_data = await self.parse_message(message)
  File "/opt/miniconda3/envs/rasa_project/lib/python3.7/site-packages/rasa/core/processor.py", line 636, in parse_message
    parse_data = self._parse_message_with_graph(message, only_output_properties)
  File "/opt/miniconda3/envs/rasa_project/lib/python3.7/site-packages/rasa/core/processor.py", line 662, in _parse_message_with_graph
    targets=[self.model_metadata.nlu_target],
  File "/opt/miniconda3/envs/rasa_project/lib/python3.7/site-packages/rasa/engine/runner/dask.py", line 101, in run
    dask_result = dask.get(run_graph, run_targets)
  File "/opt/miniconda3/envs/rasa_project/lib/python3.7/site-packages/dask/local.py", line 557, in get_sync
    **kwargs,
  File "/opt/miniconda3/envs/rasa_project/lib/python3.7/site-packages/dask/local.py", line 495, in get_async
    for key, res_info, failed in queue_get(queue).result():
  File "/opt/miniconda3/envs/rasa_project/lib/python3.7/concurrent/futures/_base.py", line 428, in result
    return self.__get_result()
  File "/opt/miniconda3/envs/rasa_project/lib/python3.7/concurrent/futures/_base.py", line 384, in __get_result
    raise self._exception
  File "/opt/miniconda3/envs/rasa_project/lib/python3.7/site-packages/dask/local.py", line 537, in submit
    fut.set_result(fn(*args, **kwargs))
  File "/opt/miniconda3/envs/rasa_project/lib/python3.7/site-packages/dask/local.py", line 233, in batch_execute_tasks
    return [execute_task(*a) for a in it]
  File "/opt/miniconda3/envs/rasa_project/lib/python3.7/site-packages/dask/local.py", line 233, in <listcomp>
    return [execute_task(*a) for a in it]
  File "/opt/miniconda3/envs/rasa_project/lib/python3.7/site-packages/dask/local.py", line 224, in execute_task
    result = pack_exception(e, dumps)
  File "/opt/miniconda3/envs/rasa_project/lib/python3.7/site-packages/dask/local.py", line 219, in execute_task
    result = _execute_task(task, data)
  File "/opt/miniconda3/envs/rasa_project/lib/python3.7/site-packages/dask/core.py", line 119, in _execute_task
    return func(*(_execute_task(a, cache) for a in args))
  File "/opt/miniconda3/envs/rasa_project/lib/python3.7/site-packages/rasa/engine/graph.py", line 473, in __call__
    ) from e
rasa.engine.exceptions.GraphComponentException: Error running graph component for node run_RegexMessageHandler.

Thanks in advance.

2

For external events, you need to hit the conversation endpoint, not the callback. You’ll see an example here. Note that the endpoint url in the example is:

http://localhost:5005/conversations/user123/trigger_intent?output_channel=latest

The docs on this endpoint are here.

Note that you’re also going to need the conversation/sender id.