Python web app on Azure function: What does exception with x-ms-error-code': 'REDACTED' mean?

Question

Sometimes we see failed requests with this exception and an unusual long response time on our FastApi/Python app running on a function:

Exception while executing function: Functions.app python exited with code 137 (0x89) 'x-ms-error-code': 'REDACTED', 'x-ms-error-code': 'REDACTED', 'x-ms-error-code': 'REDACTED'

What does that mean? I can't find info on that error online and I don't get a stack trace with it either.

Answer 1

@member45232 Thank you for reaching out to Microsoft Q&A.

Based on first part of the error message, exit code 137 is typically caused by out-of-memory issues. Please refer docs: Troubleshoot Python Exited With Code 137 for more info on this and you can use Memory profiling to analyze memory in your app as mentioned in docs.

Regarding x-ms-error-code: 'REDACTED', we have Http logging policy in Azure SDK which has default list of headers that are allowed (refer Here). All other headers will be REDACTED based on few conditions and hence you saw error message as x-ms-error-code: 'REDACTED'

I understand you didn't get Stack trace and error message didn't help much either. Will pass the feedback to our product team. In order to find exact root cause, I would require additional details and will send you a separate message.