DialogFlow Client

A java dialogflow client and processing framework for creating conversions with the google assistant.

• Serialization / Deserialization of Webhook Requests and Responses in API Version 2.
• Nice api to define conversation with support of
  • Ssml
  • Text
  • Suggestion chips
  • BasicCards
• Processing framework with annotations clear code separation

Usage

Configure the DialogFlowProcessor

Create a DialogFlowProcessor by scanning packages and automatically adding all classes annotated with @ActionHandler.

DialogFlowProcessor processor = DialogFlowProcessor.scanPackages("my.package", "some.other.package");

An ActionHandler contains a list of methods annotated with @Action("name"), where the value of the annotation matches the action it handles.

The signature of such a method returns a Conversation and can optionally take the WebhookRequest as a parameter.

@ActionHandler
class ExampleActionHandler {

    @Action("fun.cat")
    public Conversation withRequest(WebhookRequest request) {
    	...
    }

    @Action("fun.stop")
    public Conversation withoutRequest() {
    	...
    }
}

The processor can also be created manually without scanning packages and ActionHandlers can be added manually.

DialogFlowProcessor processor = new DialogFlowProcessor();

// by providing a class
processor.addActionHandler(ExampleActionHandler.class);

// by providing an instance
processor.addActionHandler(new ExampleActionHandler());

It's also possible to dynamically add ActionMethod at runtime.

processor.addActionHandler("ActionName", new ActionMethod() {
    @Override
    public Conversation handle(WebhookRequest request) {
        // do something with action "ActionName"
    }
});

processor.addActionHandler("Lambda", request -> Conversation.ask("ok"));

Processesing request

The spring way with auto mapping json via jackson.

@RestController
public class WebhookController {

    @Autowired private DialogFlowProcessor dialogFlowProcessor;

    @PostMapping(path = "/webhook")
    public WebhookResponse handleAction(@RequestBody WebhookRequest request) {
        try {
            return dialogFlowProcessor.handleRequest(request);
        } catch (ActionProcessingException e) {
            return Conversation.close("Some error").build();
        }
    }
}

Framework independent way

WebhookResponse response = null;
try {
     response = processor.handleRequest(json);
} catch (ActionProcessingException e) {
    // processing went wrong, e.g. action not found 
    response = Conversation.close("Some error").build(); 
}
    
// serialize response to json and send it back

Conversations

Conversations can be respond to in a two ways:

• Conversation.ask - let's the microphone open, so that the user can respond immediately
• Conversation.close - closes the microphone and ends the conversation

Every conversation needs to respond with at least one text that is speaken and/or shown to the user.

• Conversation.ask("Some text") - the text is spoken and shown to the user.
• Conversation.ask(new SimpleTextResponse("speech", "write")) - different text is spoken then displayed
• Conversation.ask(new SimpleSsmlResponse(ssml, "text to display")) - audio is composed by SSML;

Next to the text and audio response, conversations can have more rich responses, like

Suggestion chips

Suggestion chips are small bubbles at the end of the conversation in the chat, for easy responses when working a device with a surface.

Conversation.ask("Which do you like more?")
            .suggest("Foo", "Bar");

License

This project is licensed under the MIT License.