How to ask permission in Actions on Google without the SDK?

Question

I would like to know the name of the user, however I cannot use the nodejs sdk since I use another language.

How can I ask for permission?

I would prefer a way with the normal json responses.

Answer 1

I hacked this minimal script to get the JSON reponse which the nodejs sdk would return:

gaction.js:

const DialogflowApp = require('actions-on-google').DialogflowApp;

const app = new DialogflowApp({
    request: {
        body: {
            result: {
                action: 'Test',
                contexts: []
            }
        },
        get: (h) => h
    },
    response: {
        append: (h, v) => console.log(`${h}: ${v}`),
        status: (code) => {
            return {send: (resp) => console.log(JSON.stringify(resp, null, 2))}
        }
    }
});
function testCode(app) {
    app.askForPermission('To locate you', app.SupportedPermissions.DEVICE_PRECISE_LOCATION);
}
app.handleRequest(new Map().set('Test', testCode));

I'm still no node.js expert so this might be not an optimal solution. When you have installed node and run the command npm install actions-on-google, this will install the necessary dependencies.
When done you just need to run node gaction which will create this output:

Google-Assistant-API-Version: Google-Assistant-API-Version
Content-Type: application/json
{
  "speech": "PLACEHOLDER_FOR_PERMISSION",
  "contextOut": [
    {
      "name": "_actions_on_google_",
      "lifespan": 100,
      "parameters": {}
    }
  ],
  "data": {
    "google": {
      "expect_user_response": true,
      "no_input_prompts": [],
      "is_ssml": false,
      "system_intent": {
        "intent": "assistant.intent.action.PERMISSION",
        "spec": {
          "permission_value_spec": {
            "opt_context": "To locate you",
            "permissions": [
              "DEVICE_PRECISE_LOCATION"
            ]
          }
        }
      }
    }
  }
}

If you send now the JSON above you will be asked from Google Home. Have fun!

Answer 2

The request/response JSON formats for the API.AI webhooks with Actions is documented at https://developers.google.com/actions/apiai/webhook

As you've discovered, the data.google.permissions_request attribute contains two fields regarding the request:

1. opt_context contains a string which is read to give some context about why you're asking for the information.

2. permissions is an array of strings specifying what information you're requesting. The strings can have the values

   • NAME
   • DEVICE_COARSE_LOCATION
   • DEVICE_PRECISE_LOCATION

Answer 3

If you are using Java or Kotlin there is an Unofficial SDK. It matches the official SDK api nearly exactly. https://github.com/TicketmasterMobileStudio/actions-on-google-kotlin