Set Dialogflow response object based on user platform

Question

I have a webhook server that responds to Dialogflow with rich message objects, which work on the Google Assistant.

However, in the case the user chatting with my bot from a different platform other than Google Assitant, such as the web or Amazon Alexa, I would like to send a basic text response.

After looking through the docs, I am not sure how I can send a response message object that will display a rich message object when the user uses Google Assistant, and a plain text response on other platforms as a fallback.

This is the format of my current rich message response object, taken from the docs: https://dialogflow.com/docs/reference/agent/message-objects#basic_card_response

{
    "messages": [
      {
        "buttons": [
          {
            "openUrlAction": {
              "url": "https://linkUrl.com"
            },
            "title": "AoG Card Link title"
          }
        ],
        "formattedText": "AoG Card Description",
        "image": {
          "url": "http://imageUrl.com"
        },
        "platform": "google",
        "subtitle": "AoG Card Subtitle",
        "title": "AoG Card Title",
        "type": "basic_card"
      }
    ]
}

Answer 1

To do this, you'll just include a regular text/speech response in the messages object.

In the /query doc, check out the POST response sample.

Your JSON should look something like this:

{
    "messages": [
      {
        "buttons": [
          {
            "openUrlAction": {
              "url": "https://linkUrl.com"
            },
            "title": "AoG Card Link title"
          }
        ],
        "formattedText": "AoG Card Description",
        "image": {
          "url": "http://imageUrl.com"
        },
        "platform": "google",
        "subtitle": "AoG Card Subtitle",
        "title": "AoG Card Title",
        "type": "basic_card"
      },
      {
        "speech": "text response",
        "type": 0            
      }
    ]
}