Features

• #5006: Channel hangouts for Rasa integration with Google Hangouts Chat is now supported out-of-the-box.

• #5389: Add an optional path to a specific directory to download and cache the pre-trained model weights for HFTransformersNLP.

• #5422: Add options tensorboard_log_directory and tensorboard_log_level to EmbeddingIntentClassifier,
  DIETClasifier, ResponseSelector, EmbeddingPolicy and TEDPolicy.

  By default tensorboard_log_directory is None. If a valid directory is provided,
  metrics are written during training. After the model is trained you can take a look
  at the training metrics in tensorboard. Execute tensorboard --logdir <path-to-given-directory>.

  Metrics can either be written after every epoch (default) or for every training step.
  You can specify when to write metrics using the variable tensorboard_log_level.
  Valid values are 'epoch' and 'minibatch'.

  We also write down a model summary, i.e. layers with inputs and types, to the given directory.

Improvements

• #4756: Make response timeout configurable.
  rasa run, rasa shell and rasa x can now be started with
  --response-timeout <int> to configure a response timeout of <int> seconds.

• #4826: Add full retrieval intent name to message data
  ResponseSelector will now add the full retrieval intent name
  e.g. faq/which_version to the prediction, making it accessible
  from the tracker.

• #5258: Added PikaEventBroker (event-brokers-pika) support for publishing to
  multiple queues. Messages are now published to a fanout exchange with name
  rasa-exchange (see
  exchange-fanout
  for more information on fanout exchanges).

  The former queue key is deprecated. Queues should now be
  specified as a list in the endpoints.yml event broker config under a new key
  queues. Example config:

  event_broker:
    type: pika
    url: localhost
    username: username
    password: password
    queues:
      - queue-1
      - queue-2
      - queue-3
  

• #5416: Change rasa init to include tests/conversation_tests.md file by default.

• #5446: The endpoint PUT /conversations/<conversation_id>/tracker/events no longer
  adds session start events (to learn more about conversation sessions, please
  see session_config) in addition to the events which were sent in the request
  payload. To achieve the old behavior send a
  GET /conversations/<conversation_id>/tracker
  request before appending events.

• #5482: Make scale_loss for intents behave the same way as in versions below 1.8, but
  only scale if some of the examples in a batch has probability of the golden label more than 0.5.
  Introduce scale_loss for entities in DIETClassifier.

Bugfixes

• #5205: Fixed the bug when FormPolicy was overwriting MappingPolicy prediction (e.g. /restart).
  Priorities for mapping-policy and form-policy are no longer linear:
  FormPolicy priority is 5, but its prediction is ignored if MappingPolicy is used for prediction.

• #5215: Fixed issue related to storing Python float values as decimal.Decimal objects
  in DynamoDB tracker stores. All decimal.Decimal objects are now converted to
  float on tracker retrieval.

  Added a new docs section on tracker-stores-dynamo.

• #5356: Fixed bug where FallbackPolicy would always fall back if the fallback action is
  action_listen.

• #5361: Fixed bug where starting or ending a response with \n\n led to one of the responses returned being empty.

• #5405: Fixes issue where model always gets retrained if multiple NLU/story files are in a
  directory, by sorting the list of files.

• #5444: Fixed ambiguous logging in DIETClassifier by adding the name of the calling class to the log message.

Improved Documentation

• #2237: Restructure the "Evaluating models" documentation page and rename this page to testing-your-assistant.
• #5302: Improved documentation on how to build and deploy an action server image for use on other servers such as Rasa X deployments.

Miscellaneous internal changes

• #5340