However, once the request reaches the middleware, the header client_id is transformed into Client_id. This change in capitalization causes the following error:
Could not find a required client_id in the request, identified by HEADER or QUERY client_id
Everything was working correctly with the header sent in lowercase until June 20th.
Has anyone encountered a similar issue or have any idea what might be causing this change?
Are you implying that when it is received by the middleware that it is received as upper case, where before it was lowercase? Just trying to confirm if the change happened on the ISC side.
If you have a backup of your connector, it would be interesting to evaluate if there were changes on the connector itself. Was production and sandbox both impacted?
Is this production or sandbox? I have seen at times when the UI is modified on connectors in the past, we had some sandboxes that we had to update logic that was there previously. Not that this is the same by any means, just thinking that comparing the connector to a prior version is always a good idea and to take periodic exports.