How to read the response body on Python urllib when the status is an error like 400 which raises an exception?

Question

I\'m trying to make a request to the GitHub API with Python 3 urllib to create a release, but I made some mistake and it fails with an exception:

Answer 1

The HTTPError has a read() method that allows you to read the response body. So in your case, you should be able to do something such as:

try:
    body = urlopen(Request(
        url_template.format('api'),
        json.dumps({
            'tag_namezxcvxzcv': tag,
            'name': tag,
            'prerelease': True,
        }).encode(),
        headers={
            'Accept': 'application/vnd.github.v3+json',
            'Authorization': 'token ' + token,
        },
    )).read().decode()
except urllib.error.HTTPError as e:
    body = e.read().decode()  # Read the body of the error response

_json = json.loads(body)

The docs explain in more detail how the HTTPError instance can be used as a response, and some of its other attributes.