OAuth authentication issue during Public App integration

[ndzyadovich]

Hello everyone,

I've been using OAuth authentication flow (https://shopify.dev/tutorials/authenticate-with-oauth#verification) for past 2 years to integrate my Sales Channel with my clients' Shopify stores.

Since yesterday (April 14th 2021, 17:00UTC) I always receive errors during HMAC verification step on my side. I mean HMAC token that I generate doesn't match the one that I receive from Shopify. So that's why I unfortunately cannot have new integrations with my clients. I already tested my algorithm in different languages and libraries, and still get the same result.

Does anyone else face the same issue? Has Shopify applied any changes to HMAC generation algorithm?

I hope someone can help me with this.
Thank you!

[adityaroy]

Hi. We're also facing the same issue from last 2 days. Our App is also receiving HMAC Verification mismatch issue. The generated token doesn't match with the one provided by Shopify. The App was working fine before.

[mvpc · Accepted solution]

Hi, we ran into the same issue today, and it appears to be caused by this Shopify change: https://shopify.dev/changelog/host-parameter-added-to-the-oauth-redirect-uri. Hope this helps!

[ndzyadovich]

Thank you so much! That worked for me.