Fulfillment order notification callback not being called

We have an app that has installed a fulfillment service. I’m in the midst of updating our app to support the Fulfillment Orders API for version 2022-07.

I have opted our service into fulfillment orders and have set a callback URL. I was receiving callback notifications when fulfillment requests were made, but they are no longer being sent.

  1. Does Shopify stop sending these for a fulfillment service if they previously received an error response? Is there any other reason Shopify would stop sending these for a store/app/fulfillment service?

In my effort to get the callback handling working, a few requests may not have returned a success status. I’m working against an app installed in a development store.

  1. The documentation states that you can test the callback endpoints in your development store. How do we do this?

I see a way to send test webhooks, but not the callbacks.

Here’s the passage:

“To make sure you have everything set up correctly, you can test the callbackurl-prefixed endpoints in your development store.”

https://shopify.dev/docs/api/admin-rest/2023-01/resources/fulfillmentservice

Thanks,

Stefan

I started to receive the callbacks again! I suspect that Shopify has some kind of exponential back-off strategy for failed callback endpoints, like they do for webhooks.