Troubleshooting Bad Requests in Python Requests

The Python requests module is invaluable for making HTTP requests in your code. But sometimes you'll get back errors that need debugging. One common error is the 400 status, indicating a bad request. Here's how to troubleshoot and fix these.

When making a request like:

import requests

response = requests.get('https://api.example.com/data')

You may get back a 400 error:

requests.exceptions.HTTPError: 400 Client Error: Bad Request

This means something in your request was incorrect or improperly formatted. Here are some things to check:

Headers - Make sure you are passing the expected headers in your request. Many APIs require certain headers like authentication, content type, etc.

Parameters - If passing any URL parameters or data, double check that they are formatted correctly and contain the expected values.

URL - Check that the URL you are requesting is valid and passes any parameters properly.

Rate Limiting - Some APIs enforce rate limits, disallowing too many requests. See if headers mention limits.

Authentication - APIs often use API keys, OAuth, etc. Make sure yours is valid and properly passed.

Encoding - Try explicitly setting the encoding in your call, like requests.get(url, encoding='utf-8').

JSON Data - For posting JSON data, the headers must include 'Content-Type': 'application/json' and data should be dumped to a string using json.dumps() first.

Carefully read through the API documentation and double check that your code matches their specifications. Try the request using a tool like Postman first. And wrap your request call in a try/except to catch errors.

Debugging 400 errors takes patience - going step-by-step. Check everything in your request first before assuming the problem lies elsewhere. Pay close attention to what exactly the API requires. With care, you'll squash those bad requests!