Using the cloud functions emulator to test Dialogflow fulfillment locally - node.js

Question

Is it possible to test your Dialogflow fulfillment webhook locally using the cloud functions emulator, and if so, how should I format the request?
I've read through all the documentation I can find, including the guide at https://firebase.google.com/docs/functions/local-emulator, and of particular interest was this previous question which seems to hit on a similar point:
Unit test Actions on Google Dialogflow locally
I am able to invoke my fulfillment function with the functions shell, however no matter how I attempt to format the body I can only ever seem to trigger my fallback intent or the error catching intent.
I can verify on the Actions on Google simulator that my webhook successfully responds with the default welcome intent when given the input "hello", but when using the same request JSON data as input to my function locally, I am directed to the fallback intent.
Is it the case that the functions emulator cannot perform the proper intent-matching locally and therefore always triggers the fallback intent, or am I simply not formatting my request right? Any help would be greatly appreciated!
Here is the invocation format which I am using, and the response from the shell:
firebase > fulfillment({method: 'POST',json: true,body:
require("project/collabrec/testData.json")});
Sent request to function.
firebase > info: User function triggered, starting execution
info: Fallback intent triggered.
info: Execution took 15 ms, user function completed successfully
RESPONSE RECEIVED FROM FUNCTION: 200, {
"payload": {
"google": {
"expectUserResponse": true,
"richResponse": {
"items": [
{
"simpleResponse": {
"textToSpeech": "I didn't quite catch that. Could you say that again?"
}
}
]
}
}
}
}
Here is the testData.json content:
{
"user": {
"userId": "ABwppHFR0lfRsG_UM3NkvAptIkD2iUpIUNxFt-ia05PFuPajV6kRQKXu_H_ECMMe0lP_WcCsK64sH2MEIg8eqA",
"locale": "en-US",
"lastSeen": "2018-10-19T15:20:12Z"
},
"conversation": {
"conversationId": "ABwppHHerN4CIsBZiWg7M3Tq6NwlTWkfN-_zLIIOBcKbeaz4ruymv-nZ4TKr6ExzDv1tOzszsfcgXikgqRJ9gg",
"type": "ACTIVE",
"conversationToken": "[]"
},
"inputs": [
{
"intent": "actions.intent.TEXT",
"rawInputs": [
{
"inputType": "KEYBOARD",
"query": "hello"
}
],
"arguments": [
{
"name": "text",
"rawText": "hello",
"textValue": "hello"
}
]
}
],
"surface": {
"capabilities": [
{
"name": "actions.capability.MEDIA_RESPONSE_AUDIO"
},
{
"name": "actions.capability.SCREEN_OUTPUT"
},
{
"name": "actions.capability.AUDIO_OUTPUT"
},
{
"name": "actions.capability.WEB_BROWSER"
}
]
},
"isInSandbox": true,
"availableSurfaces": [
{
"capabilities": [
{
"name": "actions.capability.SCREEN_OUTPUT"
},
{
"name": "actions.capability.AUDIO_OUTPUT"
},
{
"name": "actions.capability.WEB_BROWSER"
}
]
}
],
"requestType": "SIMULATOR"
}
And here is my cloud function webhook:
const {dialogflow, Image} = require('actions-on-google');
const admin = require('firebase-admin');
const functions = require('firebase-functions');
const app = dialogflow();
app.catch((conv, error) => {
console.log("Error intent triggered.")
console.error(error);
conv.ask('Sorry, I ran into an error. Please try that again.');
});
app.fallback((conv) => {
console.log("Fallback intent triggered.")
conv.ask("I didn't quite catch that. Could you say that again?");
})
app.intent('Default Welcome Intent', (conv) => {
console.log("Welcome intent triggered.")
conv.ask("Welcome!!");
});
exports.fulfillment = functions.region('europe-west1').https.onRequest(app);
Using Node v8.1.4, and package versions:
"#google-cloud/common-grpc": "^0.9.0",
"#google-cloud/firestore": "^0.17.0",
"#google-cloud/functions-emulator": "^1.0.0-beta.5",
"actions-on-google": "^2.4.1",
"firebase-admin": "^6.0.0",
"firebase-functions": "^2.0.5"

Answer 1

The issue is that you're using the JSON that comes from the AoG Simulator, but this shows the JSON that AoG is sending to Dialogflow. Dialogflow processes this and sends your webhook a different JSON which includes the results of processing the AoG JSON and determining the intent, parameters, and other information.
What you are doing should work - if you have the Dialogflow JSON. You have a couple of ways to do this:
The most straighforward is to run your webhook on a place that can receive the POST from Dialogflow and look at the conv.request object, which should be able to give you the JSON you need.
If you're running the webhook on a local dev machine (as you suggest you are), I tend to start up an ngrok tunnel. The tunnel gives a public HTTPS server, which is very useful, and has the side effect of giving me a console that I can use to see exactly the contents of the request and response JSON.
Finally, you should be able to go into the project settings in Dialogflow and turn on Cloud Logging. The log includes the request that is sent to your webhook along with the response that you get from it.