DialogFlow "Webhook call failed. Error: UNKNOWN."

Question

I have a DialogFlow setup using a firebase function for fulfillments.

I attempted to add two regions to .region() in my index.js file. This led to me deleting my existing firebase function (which had been running on "us-central-1") and adding two new ones for the newly added regions.

After doing so, my dialogflow setup completely fails to do fulfillments. Instead, i get "Webhook call failed. Error: UNKNOWN" with no other details. I tried removing .region() in my index.js, thereby creating a new firebase function similar to the original, but without luck.

I have also tried to add my fulfillment code directly in the inline editor, but this does not work either.

I am at a loss for what to do here. Has anyone experienced similar issues or perhaps know a fix? Please note that the setup worked completely fine prior to adding .region() and deleting the existing firebase function.

NOTE: I am getting a weird error when deploying through the inline editor: "Permission 'cloudfunctions.functions.SetIamPolicy' denied on resource '(my resource)' (or resource may not exist)."

Answer 1

Although you moved the location of the function, you don't mention that you changed the URL for the webhook in Dialogflow to reflect this new location. The URL for Firebase Cloud Functions include the region where the function runs, so if you change the region, you also need to change the fulfillment URL.

Answer 2

Regarding the following error:

Permission 'cloudfunctions.functions.SetIamPolicy' denied on resource '(my resource)' (or resource may not exist).

I also encountered this when I deleted the function and tried to redeploy it.

I discovered that this occurs when the user (i.e. you) deploying the function does not have sufficient permissions to set IAM policies. In my case, the project was owned by another user whilst I had limited access. After being given owner access, although you likely only need permissions to manage IAM, the function deploys without any errors.