Warning: This document is for an old version of Rasa Core. The latest version is 0.14.5.

Server Configuration

Note

Before you can use the server, you need to define a domain, create training data, and train a model. You can then use the trained model for remote code execution! See the Quickstart for an introduction.

Overview

The general idea is to run the actions within your code (arbitrary language), instead of python. To do this, Rasa Core will start up a web server where you need to pass the user messages to. Rasa Core on the other side will tell you which actions you need to run. After running these actions, you need to notify the framework that you executed them and tell the model about any update of the internal dialogue state for that user. All of these interactions are done using a HTTP REST interface.

You can also use a single, simpler endpoint called /respond, which just returns all of the messages your bot should send back to the user. In general, this only works if all of your actions are simple utterances (messages sent to the user). It can make use of custom actions, but then these have to be implemented in python and executed on the machine that runs the server.

To activate the remote mode, include

action_factory: remote

within your domain.yml (you can find an example in examples/remote/concert_domain_remote.yml).

Note

If started as a HTTP server, Rasa Core will not handle output or input channels for you. That means you need to retrieve messages from the input channel (e.g. facebook messenger) and send messages to the user on your end.

Hence, you also do not need to define any utterances in your domain yaml. Just list all the actions you need.

Running the server

You can run a simple http server that handles requests using your models with

$ python -m rasa_core.server -d examples/babi/models/policy/current -u examples/babi/models/nlu/current_py2 -o out.log

The different parameters are:

  • -d, path to the Rasa Core model.
  • -u, path to the Rasa NLU model.
  • -o, path to the log file.

Starting a conversation

To start a conversation, send a POST request to the /conversation/<sender_id>/parse endpoint. <sender_id> is the conversation id (e.g. default if you just have one user, or the facebook user id or any other identifier).

$ curl -XPOST localhost:5005/conversations/default/parse -d '{"query":"hello there"}'

The server will respond with the next action you should take:

{
  "next_action": "utter_ask_howcanhelp",
  "tracker": {
    "slots": {
      "info": null,
      "cuisine": null,
      "people": null,
      "matches": null,
      "price": null,
      "location": null
    },
    "sender_id": "default",
    "latest_message": {
      ...
    }
  }
}

You now need to execute the action utter_ask_howcanhelp on your end. This might include sending a message to the output channel (e.g. back to facebook).

After you finished running the mentioned action, you need to notify Rasa Core about that:

$ curl -XPOST http://localhost:5005/conversations/default/continue -d \
    '{"executed_action": "utter_ask_howcanhelp", "events": []}'

Here the API should respond with:

{
  "next_action":"action_listen",
  "tracker": {
    "slots": {
      "info": null,
      "cuisine": null,
      "people": null,
      "matches": null,
      "price": null,
      "location": null
    },
    "sender_id": "default",
    "latest_message": {
      ...
    }
  }
}

This response tells you to wait for the next user message. You should not call the continue endpoint after you received a response containing action_listen as the next action. Instead, wait for the next user message and call /conversations/default/parse again followed by subsequent calls to /conversations/default/continue until you get action_listen again.

Events

Events allow you to modify the internal state of the dialogue. This information will be used to predict the next action. E.g. you can set slots (to store information about the user) or restart the conversation.

You can return multiple events as part of your query, e.g.:

$ curl -XPOST http://localhost:5005/conversations/default/continue -d \
    '{"executed_action": "search_restaurants", "events": [{"event": "slot", "name": "cuisine", "value": "mexican"}, {"event": "slot", "name": "people", "value": 5}]}'

Here is a list of all available events you can append to the events array in your call to /conversation/<sender_id>/continue.

Set a slot

name:slot
Examples:"events": [{"event": "slot", "name": "cuisine", "value": "mexican"}]
Description:Will set the value of the slot to the passed one. The value you set should be reasonable given the slots type.

Restart

name:restart
Examples:"events": [{"event": "restart"}]
Description:Restarts the conversation and resets all slots and past actions.

Reset Slots

name:reset_slots
Examples:"events": [{"event": "reset_slots"}]
Description:Resets all slots to their initial value.

Security Considerations

We recommend to not expose the Rasa Core server to the outside world but rather connect to it from your backend over a private connection (e.g. between docker containers).

Nevertheless, there is built in token authentication. If you specify a token when starting the server, that token needs to be passed with every request:

$ python -m rasa_core.server --auth_token thisismysecret -d examples/babi/models/policy/current -u examples/babi/models/nlu/current_py2 -o out.log

Your requests should pass the token, in our case thisismysecret, as a parameter:

$ curl -XPOST localhost:5005/conversations/default/parse?token=thisismysecret -d '{"query":"hello there"}'