Hello everyone,
I am building a flow in Power Automate that uses an HTTP action with the POST method to send a raw JSON object to an external website. The JSON object follows this format:
According to the API documentation, I need to include a Content-MD5 header with a hash generated from the payload. While I can successfully send the payload without errors using Postman, I keep encountering the following error message in Power Automate:
I have carefully reviewed the API documentation and confirmed that the header has been constructed correctly. Furthermore, to ensure the JSON payload is not altered at runtime, I have tried the following approaches, but the issue persists:
-
Copied the JSON body output from the HTTP action and used it to generate an MD5 hash.
-
Placed the payload in a Compose action and inserted it into the HTTP body.
-
Used the following formula: replace(replace(replace(string(outputs('Compose_JSON')), ' ', ''), '\n', ''), '\t', '') in a new Compose action that takes the output from the previous mentioned Compose to remove all whitespace and line breaks from the payload. I then copied the output to generate an MD5 hash.
Despite these attempts, I still receive the same error. I am beginning to suspect that Power Automate might be modifying the payload in the backend during runtime.
Has anyone encountered a similar issue or have any insights into why this might be so challenging?
