🐍 Debugging a ChunkedEncodingError in Django with requests.get()

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Recently, while working on a Django management command, I encountered an unexpected exception that had me scratching my head for a bit. It looked like this: 

requests.exceptions.ChunkedEncodingError: Connection broken: InvalidChunkLength(got length b'', 0 bytes read)

This happened while trying to fetch a remote XML file using requests.get(xml_path) in a custom Django command.

In this post, I’ll walk through what this error means, why it happens, and how you can fix or work around it.

🔍 What’s Happening?

The stack trace led me to this line inside a Django management command:

response = requests.get(xml_path)

Eventually, the request failed with:


requests.exceptions.ChunkedEncodingError: 
("Connection broken: InvalidChunkLength(got length b'', 0 bytes read)", 
 InvalidChunkLength(got length b'', 0 bytes read))

This is a ChunkedEncodingError, and it's triggered when the remote server sends a malformed or incomplete chunked HTTP response — for example, when the chunk size is missing or corrupted.

✅ How to Fix It

There are a few ways to approach this, depending on the root cause and how critical the request is to your workflow.

1. Retry the Request

Sometimes it's just a flaky network or temporary server hiccup. You can wrap the call in a retry loop like so:

import requests
from requests.exceptions import ChunkedEncodingError
import time

for attempt in range(3):
    try:
        response = requests.get(xml_path)
        break  # success
    except ChunkedEncodingError as e:
        print(f"Attempt {attempt+1}: ChunkedEncodingError: {e}")
        time.sleep(2)
else:
    raise Exception("Failed after 3 attempts")

This simple retry logic can make your command more resilient to temporary issues.

2. Watch Your stream=True Usage

If you're using:

requests.get(xml_path, stream=True)

...make sure you're consuming the response correctly and fully. Improper streaming can lead to incomplete reads and errors. If you don’t need streaming, just disable it:

response = requests.get(xml_path, stream=False)

3. Check the Source Server

The issue might not be in your code at all. If the server you're calling is returning bad chunked responses, it’s good to inspect it directly:

curl -v <xml_path>

Look for any irregularities in the transfer encoding or malformed chunk data.

4. Update requests

A bug in an older version of the requests library could be at play. Update to the latest version with:

pip install --upgrade requests

Always a good move when chasing down mysterious network errors.

🔧 Bonus Tip: Logging and Backoff

For production usage, consider adding proper logging and exponential backoff with tools like tenacity or a custom retry mechanism. That way, you avoid hammering a struggling server.

🧠 Final Thoughts

Errors like ChunkedEncodingError are a good reminder that network calls are fragile by nature — even simple GET requests. Wrapping them with retries and good diagnostics can save you (and your users) a lot of trouble.

Have you run into similar issues in Django or other Python projects? Let’s debug together.

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