io.spokestack.spokestack.rasa

Class RasaOpenSourceNLU

java.lang.Object

io.spokestack.spokestack.rasa.RasaOpenSourceNLU

All Implemented Interfaces:

NLUService, AutoCloseable

public final class RasaOpenSourceNLU
extends Object
implements NLUService

An NLU component that submits utterances to a Rasa Open Source server to retrieve responses.

Since the input for a Rasa Open Source request is a user utterance, this component occupies the position in Spokestack of an NLU, but a Rasa webhook response includes results from the dialogue model, leaving out NLU results. Therefore, this component returns a constant value as the intent and includes the webhook response as a list inside the result context under a "responses" key.

This component is designed to be used with a DialogueManager built with a RasaDialoguePolicy policy, which expects results in the format just described and converts the Rasa responses into TTS prompts or app events as appropriate.

This component supports the following configuration properties:

• rasa-oss-url (string, required): URL to the Rasa Open Source server. This component is designed to use Rasa's REST channel.
• rasa-sender-id (string, optional): Sender ID for Rasa requests. Defaults to "spokestack-android".
• rasa-oss-token (string, optional): Token to use in requests to the Rasa Open Source server. See Rasa's documentation for more details.
• rasa-oss-jwt (string, optional): A full JWT header (including the "Bearer " prefix) to use in requests to the Rasa Open Source server. See Rasa's documentation for more details.

Field Summary

Fields

Modifier and Type	Field and Description
static String	RASA_INTENT The designated intent produced by this component since Rasa Open Source responses do not include classification results.
static String	RESPONSE_KEY The designated key for response messages from Rasa Open Source in an NLUResult produced by this component.

Constructor Summary

Constructors

Constructor and Description
RasaOpenSourceNLU(SpeechConfig config, NLUContext nluContext) Create a new Rasa Open Source NLU component.

Method Summary

Modifier and Type	Method and Description
AsyncResult<NLUResult>	classify(String utterance, NLUContext nluContext) Classifies a user utterance.
void	close()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

RASA_INTENT

public static final String RASA_INTENT

The designated intent produced by this component since Rasa Open Source responses do not include classification results.

See Also:

Constant Field Values

RESPONSE_KEY

public static final String RESPONSE_KEY

The designated key for response messages from Rasa Open Source in an NLUResult produced by this component.

See Also:

Constant Field Values

Constructor Detail

RasaOpenSourceNLU

public RasaOpenSourceNLU(SpeechConfig config,
                         NLUContext nluContext)

Create a new Rasa Open Source NLU component.

Parameters:

config - configuration properties

nluContext - The NLU context used to dispatch trace events and errors.

Method Detail

classify

public AsyncResult<NLUResult> classify(String utterance,
                                       NLUContext nluContext)

Description copied from interface: NLUService

Classifies a user utterance. Classification should be performed on a background thread, but the use of an AsyncResult allows the caller to either block while waiting for a result or register a callback to be executed when the result is available.

Specified by:

classify in interface NLUService

Parameters:

utterance - The user utterance to be classified.

nluContext - The current NLU context, containing request metadata and the ability to fire trace events.

Returns:

An AsyncResult representing the result of the classification task.

See Also:

AsyncResult.registerCallback(io.spokestack.spokestack.util.Callback)

close

public void close()
           throws Exception

Specified by:

close in interface AutoCloseable

Throws:

Exception