rasa-webchat VS rasa-dev-tutorial

For this, people will chat with the bot using this tool -> https://github.com/botfront/rasa-webchat

The web chat we created does not support all Rasa functionality and it could be improved in many ways. If you want to add Rasa chat to your webpage, consider rasa-webchat which provides more features.

There is a python framework named Rasa, it s really easy and is open source. I use it at work. As for the frontend, you can use botfront ui. https://github.com/RasaHQ/rasa https://github.com/botfront/rasa-webchat

We already had the and and only added the two elements which contain a element. We want the feature to be disabled by default and display only the volume off icon. Hence we hide the volume on icon by adding style="display: none" to it. Styles Let's make the button nicer by adding this to the tag in the :

.voice-icon {
    fill: currentColor;
    font-size: 22px;
    width: 1em;
}

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This should be the result:

JavaScript

The last step is to add the behaviour.
Let's create a toggleVoice function and add it as a click listener to the two buttons.

let voiceEnabled = false;
const iconVolumeOn = document.getElementById('icon-volume-on');
const iconVolumeOff = document.getElementById('icon-volume-off');

function toggleVoice() {
    if (voiceEnabled) {
        voiceEnabled = false;
        iconVolumeOn.style.display = 'none';
        iconVolumeOff.style.display = 'block';
    } else {
        if ('speechSynthesis' in window) {
            voiceEnabled = true;
            iconVolumeOn.style.display = 'block';
            iconVolumeOff.style.display = 'none';
        } else {
            alert("Sorry, your browser doesn't support text to speech.");
        }
    }
}

iconVolumeOn.addEventListener('click', toggleVoice);
iconVolumeOff.addEventListener('click', toggleVoice);

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Depending on whether the voice is enabled or disabled, the function displays the appropriate icon and hides the other icon. It also sets voiceEnabled accordingly. The voice is enabled only when the SpeechSynthesis API is supported by the user's browser (this API is described later on).

You can now toggle the button:

For the text-to-speech, we'll use Web Speech API. It allows us to create a SpeechSynthesisUtterance instance to which we assign a text.
When this instance is passed to the window.speechSynthesis.speak function, the browser reads the text aloud.

We want to read aloud every message from the chatbot after it is received, therefore we add this code at the end of the appendMessage function:

if (voiceEnabled && type === "received") {
    const voiceMsg = new SpeechSynthesisUtterance();
    voiceMsg.text = msg;
    window.speechSynthesis.speak(voiceMsg);
}

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That's it!

Run the application

1. Serve the application on http://localhost:8080 by running npx http-server webchat.
2. In a new terminal window, run the rasa server with enabled cors for all origins: rasa run --cors "*".
3. In another terminal window, run the actions server: rasa run actions.
4. Open http://127.0.0.1:8080 and chat with the chatbot!

Repository for this tutorial:

petr7555 / rasa-dev-tutorial

You can checkout the state of the repository at the end of this tutorial by running:

git clone --branch 23-text-to-speech [email protected]:petr7555/rasa-dev-tutorial.git

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All that is left is a client. Create a folder named webchat in the Rasa chatbot project. Inside the webchat folder, create a new index.html file. This file will contain the source code for the interactive web chat. You can view the complete code here.

Add the action also to the tests.