I'm getting backend failure error in google smart home while accessing fulfillment URL provided in dialogflow webhook url

Question

I'm getting backend failure error in google smart home while accessing fulfillment URL provided in dialogflow webhook url

{
   textPayload: "SYNC: Request ID 1570058940383905256 failed with code: BACKEND_FAILURE"
   insertId: "1trptjqgc2uhm9d"
   resource: {
   type: "assistant_action"
   labels: {
   action_id: "SMART_HOME_SYNC"
   project_id: "gnextsmarthome"
   version_id: ""
  }
}

Action console Account linking details:

   Authorization URL: https://accounts.google.com/o/oauth2/auth
   Token URL :https://oauth2.googleapis.com/token

through voice assistant able to access fulfillment url successfully,but failed to access through google home while linking app. also prebuilt smart home action option not visible in Action menu

I referred to this example to build smart home app:

https://github.com/shivasiddharth/google-actions-smarthome

In that example,they had used fake access token and auth url.

In order to use google signin concept, I have added google account token url: https://accounts.google.com/o/oauth2/auth and then end up with error 'Google account error'.(fig 1)

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and also account linking type option is missing.but in this case able to see smart home prebuilt action(fig 2)

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But later i noticed account linking type option become visible after enabling with dialogflow api.then 'google account error' is gone.

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in this case i have mentioned fulfillment url in dialogflow webhook address to trigger smart home backend server function.

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Answer 1

You are trying to use an endpoint which can’t be used and hence you will have to use your own endpoints as also mentioned in the comments on this answer. You can try out the Connect smart home devices to the Google Assistant codelab to see if the error is due to a configuration, or the server you are running behind your endpoint.

If you are still running into issues when implementing your own fulfillment endpoint, you can take a look at your error logs to see what the detailed debug string comes out as. You can learn more from the Troubleshooting Guide.