Tags:

• aura-bot
• middleware

Categories:

• components

Aura Bot recognizers

What are Aura Bot recognizers?

Recognizers in aura-bot are a specific type of middlewares that are executed in a certain stage of the message flow. They are in charge of the recognition of the user’s intention based on the data sent in the request.

Recognizers inherit from the abstract class called BaseRecognizerMiddleware.

There are two types of recognizers, internal and external:

Internal recognizers

aura-bot own components that are able to recognize the intention of the user directly from the incoming message. Currently, they are:

• aura-command-recognizer-middleware
• dialog-context-recognizer-middleware
• attachment-recognizer-middleware
• file-manager-recognizer-middleware
• prompt-check-recognizer-middleware
• value-command-recognizer-middleware
• text-command-recognizer-middleware
• triage-recognizer-middleware

External recognizers

Responsible for calling an external API to obtain an intention.
Currently, the only external recognizer is nlp-recognizer-middleware, in charge of detecting the intention of the user from all the training of the environment.

Apart from the ones mentioned above, the finalize-recognizers-middleware is in charge of finalizing the recognition process.

Recognizers are executed sequentially in the order previously defined during the bot start-up.

Recognizers flow

The following figure shows the execution flowchart for aura-bot recognizers, including the recognizers included in aura-bot by default. They are executed sequentially.

• If one specific recognizer has obtained an intention, then the flow redirects to the finalize-recognizers-middleware, that provides the result to aura-bot in order to trigger the corresponding dialog.

• If the recognizer in execution does not get the intention, then the flow continues and the succeeding recognizer is executed.

• As can be seen in the flowchart, the last recognizer to be executed is the external one, nlp-recognizer-middleware. This is because aura-bot should only request it if no other recognizer gets the intention of the user.

• The finalize-recognizers-middleware is in charge of deciding, in case there is any active prompt, whether to continue with the prompt or to remove the prompt from the dialog stack and process the attempt to start a new dialog otherwise.