Django POST error: response variable not associated with a value error

This one for python wizards. I got next code in some of my messenger class:

        response: Dict[str, Any] | None = None
        try:
            response = self.client.post("url/", data=payload)

            if not response or not response.get("ok"):
                logger.warning(
                    "[MessageService sync_chat] " +
                    "Server responded without confirmation (ok=False) for chat '%s'",
                    chat.chat_id
                )
                return {"status": SyncStatus.NOT_CONFIRMED}

            self._mark_messages_as_synced(messages)
            logger.info(
                "[MessageService sync_chat] " +
                "Synced %d messages for chat '%s'",
                len(incoming_messages), chat.chat_id
            )
            return {'response': response, 'status': SyncStatus.SUCCESS}
        except Exception as e:
            logger.warning(
                "[MessageService sync_chat] " + "Skipping chat '%s' due to error: %s\nResponse: %s",
                chat.chat_id, str(e)
            )
            return {"status": SyncStatus.ERROR, "reason": str(e)}

And somehow I got an error in this try-except block:

WARNING [MessageService sync_chat] Skipping chat '7925606@c.us' due to error:
    cannot access local variable 'response' where it is not associated with a value

Even if I initialized response before, python still got no access to it. Because of that, I can't even check what is wrong with my request.

great question — you're running into a classic Python scoping quirk.

Even though you declared:

response: Dict[str, Any] | None = None

the issue happens if an exception is raised during this line:

response = self.client.post("url/", data=payload)

If that line throws an error (say, due to a bad connection, timeout, etc.), Python never completes the assignment, so response is never actually bound in the current scope.

As a result, when you try to reference response in the except block:

except Exception as e:     logger.warning("...", response)

Python says:


UnboundLocalError: cannot access local variable 'response' where it is not associated with a value

Safely check if the variable exists before using it in the except block. You can do:

except Exception as e:     logger.warning(         "[MessageService sync_chat] Skipping chat '%s' due to error: %s\nResponse: %s",         chat.chat_id,         str(e),         repr(response) if 'response' in locals() else 'No response'     )

Or predefine a separate variable for logging:

response_info = "No response" try:     response = self.client.post("url/", data=payload)     response_info = repr(response)     ... except Exception as e:     logger.warning(         "[MessageService sync_chat] Skipping chat '%s' due to error: %s\nResponse: %s",         chat.chat_id, str(e), response_info     )

This approach avoids the locals() check and keeps your logging logic clean and safe.

@ТимурУсманов You're welcome. I'm glad it helped you further debug the issue. Best of luck with the rest!

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