Method send_trailers

gunicorn/http2/async_connection.py:483–525

Send trailing headers on a stream. Trailers are headers sent after the response body, commonly used for gRPC status codes, checksums, and timing information. Args: stream_id: The stream ID trailers: List of (name, value) trailer tuples Raise

(self, stream_id, trailers)

            return False

    async def send_trailers(self, stream_id, trailers):
        """Send trailing headers on a stream.

        Trailers are headers sent after the response body, commonly used
        for gRPC status codes, checksums, and timing information.

        Args:
            stream_id: The stream ID
            trailers: List of (name, value) trailer tuples

        Raises:
            HTTP2Error: If stream not found, headers not sent, or pseudo-headers used

        Returns:
            bool: True if trailers sent, False if stream was already closed
        """
        stream = self.streams.get(stream_id)
        if stream is None:
            # Stream was already cleaned up (reset/closed) - return gracefully
            return False
        if not stream.response_headers_sent:
            # Can't send trailers without headers - return False
            return False

        # Validate and normalize trailer headers
        trailer_headers = []
        for name, value in trailers:
            lname = name.lower()
            if lname.startswith(':'):
                raise HTTP2Error(f"Pseudo-header '{name}' not allowed in trailers")
            trailer_headers.append((lname, str(value)))

        try:
            # Send trailers with end_stream=True
            self.h2_conn.send_headers(stream_id, trailer_headers, end_stream=True)
            stream.send_trailers(trailer_headers)
            await self._send_pending_data()
            return True
        except _h2_exceptions.StreamClosedError:
            # Stream was reset by client - clean up gracefully
            stream.close()
            self.cleanup_stream(stream_id)
            return False

    async def send_error(self, stream_id, status_code, message=None):
        """Send an error response on a stream."""