hpack API

This document provides the HPACK API.

class hpack.Encoder

An HPACK encoder object. This object takes HTTP headers and emits encoded HTTP/2 header blocks.

encode(headers, huffman=True)

Takes a set of headers and encodes them into a HPACK-encoded header block.

Parameters:
  • headers –

    The headers to encode. Must be either an iterable of tuples or a dict.

    If an iterable of tuples, the tuples may be either two-tuples or three-tuples. If they are two-tuples, the tuples must be of the format (name, value). If they are three-tuples, they must be of the format (name, value, sensitive), where sensitive is a boolean value indicating whether the header should be added to header tables anywhere. If not present, sensitive defaults to False.

  • huffman – (optional) Whether to Huffman-encode any header sent as a literal value. Except for use when debugging, it is recommended that this be left enabled.
Returns:

A bytestring containing the HPACK-encoded header block.
header_table_size

Controls the size of the HPACK header table.

class hpack.Decoder

An HPACK decoder object.

decode(data, raw=False)

Takes an HPACK-encoded header block and decodes it into a header set.

Parameters:
  • data – A bytestring representing a complete HPACK-encoded header block.
  • raw – (optional) Whether to return the headers as tuples of raw byte strings or to decode them as UTF-8 before returning them. The default value is False, which returns tuples of Unicode strings
Returns:

A list of two-tuples of (name, value) representing the HPACK-encoded headers, in the order they were decoded.
Raises:

HPACKDecodingError – If an error is encountered while decoding the header block.
header_table_size

Controls the size of the HPACK header table.

class hpack.HPACKError

The base class for all hpack exceptions.

class hpack.HPACKDecodingError

An error has been encountered while performing HPACK decoding.

class hpack.InvalidTableIndex

An invalid table index was received.