Error calling BaseHTTPRequestHandler.end_headers()

[jnewbigin]

Bug report

Bug description:

If a call is made to BaseHTTPRequestHandler.end_headers() but no headers or response have been queued, an exception is raised exposing implementation details.

    class request_handler(BaseHTTPRequestHandler):
        def do_GET(self):
            self.end_headers()

Actual result

AttributeError("'request_handler' object has no attribute '_headers_buffer'")

Expected result:

pass

flush_headers has a guard to check if the buffer has been allocated which is missing from end_headers

if hasattr(self, '_headers_buffer'):

CPython versions tested on:

CPython main branch

Operating systems tested on:

Linux

Linked PRs

• gh-131715 Fix Error calling BaseHTTPRequestHandler.end_headers() #131718