This is an older thread but using Shopify Flow (now available for regular stores along with Plus) might do the trick here. You can send HTTP requests based on tags, updates, etc that also trigger other backend options. You can submit variables like x-guid’s or x-api-key’s and what has eally helped for stores in product and development environments, save these keys as global metaobjects to retrieve wherever, making it easier to port over the flow without having to re-add too many attributes.
I agree. Where do we find the app password.
I just have an api key & secret and how on earth, are we supposed to know about this information, with respect to the URL? I mean why has Shopify Admin not written this down in the official documentation? We shouldn’t have to trawl through every single community post to find this stuff.
NOT GOOD ENOUGH, AGAIN, SHOPIFY!!! 
Exactly the same issue with the same error.
Why is this so complicated? It should just work?
Good grief. I have now been stuck on this issue for 2 days! 
Why can’t Shopify add clearer documentation about this stuff?
Please could you provide any insight, if you are able to, as to why my GraphQl call is not working [see image]
Thank you, in advance…
I am assuming that the Client ID represents the X-Shopify-Access-Token?
When I try the same query in the Shopify Admin GraphQl IDE App, it works perfectly?
But, the problem is, when I try this query inside my Remix based admin app, it fails with the same authentication error, as Postman displays?