Power Platform Community Forum Thread Details

Hi everyone,

I am struggling with a Custom Connector issue in a Canvas App. I am trying to perform a PATCH request to an API that requires the Content-Type application/json-patch+json. The body must be a valid JSON Patch array.

The Problem:
Even though I have defined the consumes type as application/json-patch+json in the Swagger file and I am passing the header explicitly in the Power Fx formula, Power Apps keeps overriding the Content-Type header to application/json in the actual network call.

What I have tried:

Standard Approach: Defined the body as an array in Swagger. Power Fx:
Connector.PatchAction(id, "application/json-patch+json", [{op: "replace", path: "...", value: "..."}])
Result: Power Apps forces Content-Type: application/json and the API returns 415 Unsupported Media Type.
The String Trick: Changed the Swagger body schema to type: string to prevent Power Apps from interpreting the object. Power Fx:
Connector.PatchAction(id, "application/json-patch+json", JSON([...], JSONFormat.Compact))
Result: The Power Apps Monitor shows the header is still being overwritten or the body is being double-escaped as a string literal, which the API also rejects.
Static Header in Swagger: Set the header to internal with a default value in the Swagger file.
Result: Power Apps seems to ignore the internal default and still applies its own logic based on the body's data type.

Current Request Details (from Monitor):

Method: PATCH
Actual Header sent: "Content-Type": "application/json" (should be application/json-patch+json)
Expected Body Format: [{"op":"replace", "path":"/registeredUser", "value":"user@mail.com"}]

Question:
How can I force a Power Apps Custom Connector to respect the application/json-patch+json content type when sending an array/object? Is there a way to stop the "intelligent" header overriding behavior of the Power Apps runtime?

Categories:

Building Power Apps

Connector development

General topics