Google Action / Dialogflow : how to ask for geolocation - actions-on-google

Question

I'm trying to implement a simple app for Google Assistant.
All works fine, but now I have a problem with the "permission" helper :
https://developers.google.com/actions/assistant/helpers#helper_intents
I have an intent connected with webhook to my java application. When an user types a sentence similar to "near to me", I want to ask to him his location and then use lat/lon to perform a search.
es: Brazilian restaurant near to me
my intent "searchRestaurant" is fired
I receive the webhook request and I parse it
if I find a parameter that is connected to a sentence like "near to me", so instead to response with a "Card" or a "List" I return a JSON that represent the helper request :
{
"conversationToken": "[]",
"expectUserResponse": true,
"expectedInputs": [
{
"inputPrompt": {
"initialPrompts": [
{
"textToSpeech": "PLACEHOLDER_FOR_PERMISSION"
}
],
"noInputPrompts": []
},
"possibileIntents": [
{
"intent": "actions.intent.PERMISSION",
"inputValueData": {
"#type": "type.googleapis.com/google.actions.v2.PermissionValueSpec",
"optContext": "Posso accedere alla tua posizione?",
"permission": [
"NAME",
"DEVICE_PRECISE_LOCATION"
]
}
}
]
}
]
}
but something seems to be wrong, and I receive an error:
"{\n \"responseMetadata\": {\n \"status\": {\n \"code\": 10,\n \"message\": \"Failed to parse Dialogflow response into AppResponse because of empty speech response\",\n \"details\": [{\n \"#type\": \"type.googleapis.com/google.protobuf.Value\",\n \"value\": \"{\\"id\\":\\"1cc45c5e-c398-4ea7-98a5-408f31ce142d\\",\\"timestamp\\":\\"2018-08-02T14:45:05.752Z\\",\\"lang\\":\\"it\\",\\"result\\":{},\\"alternateResult\\":{},\\"status\\":{\\"code\\":206,\\"errorType\\":\\"partial_content\\",\\"errorDetails\\":\\"Webhook call failed. Error: Failed to parse webhook JSON response: Cannot find field: conversationToken in message google.cloud.dialogflow.v2.WebhookResponse.\\"},\\"sessionId\\":\\"1533221100163\\"}\"\n }]\n }\n }\n}"
The "conversationToken" is filled, so I don't understand the error message.
Maybe I'm trying to perform the operation in a wrong way.
So, which is the correct way to call this helper?
--> I've created a second intent "askGeolocation" that have "actions_intent_PERMISSION" as "Event", and ... if I understand correctly the documentation, should be trigger if the request for helper is correct.
How can I get this working?
UPDATE :
I find some example of the json response for ask permission and seems that it should be different from the one above that i'm using :
https://github.com/dialogflow/fulfillment-webhook-json/blob/master/responses/v2/ActionsOnGoogle/AskForPermission.json
{
"payload": {
"google": {
"expectUserResponse": true,
"systemIntent": {
"intent": "actions.intent.PERMISSION",
"data": {
"#type": "type.googleapis.com/google.actions.v2.PermissionValueSpec",
"optContext": "To deliver your order",
"permissions": [
"NAME",
"DEVICE_PRECISE_LOCATION"
]
}
}
}
}
}
so, i've implemented it and now the response seems to be good (no more error on parsing it), but i still receive an error on it validation :
UnparseableJsonResponse
API Version 2: Failed to parse JSON response string with 'INVALID_ARGUMENT' error: "permission: Cannot find field."
so, a problem still persist.
Anyone know the cause?
Thanks

Answer 1

After some tests i found the problem.
I was returning a wrong json repsonse with "permission" instead of "permissions":
"permission**s**": [
"NAME",
"DEVICE_PRECISE_LOCATION"
]
So the steps to ask for location are correct. I report them here as a little tutorial in order to help who is facing on it for the first time:
1) In DialogFlow, add some logic to your Intent, in order to understand when is ok to ask to user his location. In my case, i've added a "parameter" that identify sentences like "nearby" and so on.
2) When my Intent is fired i receive to my java application a request like this :
...
"queryResult": {
"queryText": "ristorante argentino qui vicino",
"action": "bycategory",
"parameters": {
"askgeolocation": "qui vicino",
"TipoRistorante": ["ristorante", "argentino"]
},
...
3) If "askgeolocation" parameter is filled, instead to return a "simple message" o other type of message, i return a json for ask the permission to geolocation :
{
"payload": {
"google": {
"expectUserResponse": true,
"systemIntent": {
"intent": "actions.intent.PERMISSION",
"data": {
"#type": "type.googleapis.com/google.actions.v2.PermissionValueSpec",
"optContext": "To deliver your order",
"permissions": [
"NAME",
"DEVICE_PRECISE_LOCATION"
]
}
}
}
}
}
4) You MUST have a second Intent that is configured with "actions_intent_PERMISSION " event :
No training phrases
No Action and params
No Responses
But with Fulfillment active :
5) Once your response arrive to Google Assistant this is the message that appear :
6) Now, if user answer "ok" you receive this json on your webhook :
{
"responseId": "32cf46cf-80d8-xxxxxxxxxxxxxxxxxxxxx",
"queryResult": {
"queryText": "actions_intent_PERMISSION",
"action": "geoposition",
"parameters": {
},
"allRequiredParamsPresent": true,
"fulfillmentMessages": [{
"text": {
"text": [""]
}
}],
"outputContexts": [{
"name": "projects/xxxxxxxxxxxxxxxxxxxxx"
}, {
"name": "projects/xxxxxxxxxxxxxxxxxxxxx",
"parameters": {
"PERMISSION": true
}
}, {
"name": "projects/xxxxxxxxxxxxxxxxxxxxx"
}, {
"name": "projects/xxxxxxxxxxxxxxxxxxxxx"
}, {
"name": "projects/xxxxxxxxxxxxxxxxxxxxx"
}, {
"name": "projects/xxxxxxxxxxxxxxxxxxxxx"
}],
"intent": {
"name": "projects/xxxxxxxxxxxxxxxxxxxxx",
"displayName": "geoposition"
},
"intentDetectionConfidence": 1.0,
"languageCode": "it"
},
"originalDetectIntentRequest": {
"source": "google",
"version": "2",
"payload": {
"isInSandbox": true,
"surface": {
"capabilities": [{
"name": "actions.capability.MEDIA_RESPONSE_AUDIO"
}, {
"name": "actions.capability.SCREEN_OUTPUT"
}, {
"name": "actions.capability.AUDIO_OUTPUT"
}, {
"name": "actions.capability.WEB_BROWSER"
}]
},
"requestType": "SIMULATOR",
"inputs": [{
"rawInputs": [{
"inputType": "KEYBOARD"
}],
"arguments": [{
"textValue": "true",
"name": "PERMISSION",
"boolValue": true
}],
"intent": "actions.intent.PERMISSION"
}],
"user": {
"lastSeen": "2018-08-03T08:55:20Z",
"permissions": ["NAME", "DEVICE_PRECISE_LOCATION"],
"profile": {
"displayName": ".... full name of the user ...",
"givenName": "... name ...",
"familyName": "... surname ..."
},
"locale": "it-IT",
"userId": "xxxxxxxxxxxxxxxxxxxxx"
},
"device": {
"location": {
"coordinates": {
"latitude": 45.xxxxxx,
"longitude": 9.xxxxxx
}
}
},
"conversation": {
"conversationId": "xxxxxxxxxxxxxxxxxxxxx",
"type": "ACTIVE",
"conversationToken": "[]"
},
"availableSurfaces": [{
"capabilities": [{
"name": "actions.capability.SCREEN_OUTPUT"
}, {
"name": "actions.capability.AUDIO_OUTPUT"
}, {
"name": "actions.capability.WEB_BROWSER"
}]
}]
}
},
"session": "projects/xxxxxxxxxxxxxxxxxxxxx"
}
that contains, name/surname and latitude/longitude. This information can be saved in your application, in order to not perform again this steps.
I hope this helps.
Davide

Answer 2

In your intent, you can ask for a parameter with a custom Entity. This you can do like this:
entity you can define as "near"
put all the synonyms for near for which you want to trigger location permission in this entity
do not mark this parameter as "required"
do not put any prompt
in the training phrases, add some phrases with this parameter
in your webhook, keep a check on the parameter, if present ask for permission if not continue.
add a permission event to another intent
do your post permission processing in that intent
Entity
Intent
I hope you get it.

Answer 3

There are samples on this topic specifically that guide you through exactly what's needed for requesting permissions in Node and Java.
Note: There are helper intents samples available in Node and Java as well.