Dialogflow Messenger JavaScript events

Dialogflow Messenger triggers a variety of events that you can create event listeners for. Some events have a detail object field, which provides more information about the event.

df-messenger-loaded

The agent dialog is first loaded.

Detail properties:

• none

For example:

window.addEventListener('df-messenger-loaded', () => {
  // Messenger is now ready.
});

df-chat-open-changed

The chat is opened or closed.

Note: Only active if the df-messenger-chat-bubble is used.

Detail properties:

• isOpen (boolean): new state of the chat

For example:

window.addEventListener('df-chat-open-changed', (event) => {
  console.log(`Chat is ${event.detail.isOpen ? 'open' : 'closed'}`);
});

df-user-input-entered

The user entered text.

Detail properties:

• input (string): value the user entered

For example:

window.addEventListener('df-user-input-entered', (event) => {
  console.log(event.detail.input);
});

df-request-sent

A request sent to the Dialogflow backend.

Note: The request can be manipulated. The changes are reflected in the request being sent. If the event's default is prevented, the request won't be sent.

Detail properties:

• data (object): data container
• data.requestBody (object): request that was sent

For example:

window.addEventListener('df-request-sent', (event) => {
  console.log('Request', event.detail.data.requestBody);
});

window.addEventListener('df-request-sent', (event) => {
  event.preventDefault(); // Dialogflow Messenger won't send the request.

  // Send request yourself.
});

df-response-received

A response has arrived to the agent dialog.

Note: Messages can be manipulated, the changes will be reflected in the agent's response handling. If the event's default is prevented, the agent won't handle the response.

Detail properties:

• data (object): data container
• data.messages (object[]): list of parsed response messages
• raw (object): verbatim response that was received

For example:

window.addEventListener('df-response-received', (event) => {
  // Remove all non-text messages.
  event.detail.data.messages = event.detail.data.messages.filter(message => {
    return message.type === 'text';
  });
});

window.addEventListener('df-response-received', (event) => {
  event.preventDefault(); // Dialogflow Messenger won't handle the response.

  const messenger = document.querySelector('df-messenger');
  event.detail.data.messages.forEach(message => {
    if (message.type === 'text') {
      messenger.renderCustomText(message.text);
    }
  });
});

df-messenger-error

A request to the backend fails.

Detail properties:

• error (object): error that occurred

For example:

window.addEventListener('df-messenger-error', (event) => {
  console.log(event.detail.error);
});

df-session-expired

The session with the agent expired.

Detail properties:

• none

For example:

window.addEventListener('df-session-expired', () => {
  const messenger = document.querySelector('df-messenger');
  messenger.renderCustomText(`*Session expired*`, /* isBot= */ true);
  messenger.startNewSession({ retainHistory: true });
});

df-session-ended

The session has ended.

Detail properties:

• none

For example:

window.addEventListener('df-session-ended', () => {
  const messenger = document.querySelector('df-messenger');
  messenger.renderCustomText(`*Session ended*`, /* isBot= */ true);
  messenger.startNewSession({ retainHistory: true });
});

df-url-suggested

URLs of suggested resources.

Detail properties:

• suggestedUrls (string[]): list of suggested URLs

For example:

window.addEventListener('df-url-suggested', (event) => {
  if (event.detail.suggestedUrls.length === 1) {
    window.location.href = event.detail.suggestedUrls[0];
  }
});

df-accordion-clicked

User clicked the accordion.

Detail properties:

• none

df-button-clicked

User clicked a button.

Detail properties:

• actionLink (string): anchor href of the clicked button, if specified
• event (string): event of the clicked button, if specified
• languageCode (string): language code of the event if specified, otherwise the main language code
• text (string): text of the clicked button

window.addEventListener('df-button-clicked', (event) => {
  event.preventDefault(); // Dialogflow Messenger won't send the "event" request.

  // Handle "event" yourself.
});

df-chip-clicked

User clicked a chip.

Detail properties:

• actionLink (string): anchor href of the clicked chip, if specified
• text (string): text of the clicked chip

df-citation-clicked

User clicked a citation.

Detail properties:

• actionLink (string): anchor href of the citation
• title (string): title of the citation

df-info-card-clicked

User clicked an info-card.

Detail properties:

• actionLink (string): anchor href of the info-card
• title (string): title of the info-card

df-list-element-clicked

User clicked a list element.

Detail properties:

• actionLink (string): anchor href of the list element, if specified
• event (string): event of the clicked list element, if specified
• languageCode (string): language code of the event if specified, otherwise the main language code
• title (string): title of the list element

window.addEventListener('df-list-element-clicked', (event) => {
  event.preventDefault(); // Dialogflow Messenger won't send the "event" request.

  // Handle "event" yourself.
});

df-image-clicked

User clicked an image.

Detail properties:

• actionLink (string): anchor href of the image, if specified