Metadata-Version: 2.0
Name: h2
Version: 2.5.0
Summary: HTTP/2 State-Machine based protocol implementation
Home-page: http://hyper.rtfd.org
Author: Cory Benfield
Author-email: cory@lukasa.co.uk
License: MIT License
Platform: UNKNOWN
Classifier: Development Status :: 5 - Production/Stable
Classifier: Intended Audience :: Developers
Classifier: License :: OSI Approved :: MIT License
Classifier: Programming Language :: Python
Classifier: Programming Language :: Python :: 2
Classifier: Programming Language :: Python :: 2.7
Classifier: Programming Language :: Python :: 3
Classifier: Programming Language :: Python :: 3.3
Classifier: Programming Language :: Python :: 3.4
Classifier: Programming Language :: Python :: 3.5
Classifier: Programming Language :: Python :: Implementation :: CPython
Classifier: Programming Language :: Python :: Implementation :: PyPy
Requires-Dist: hpack (>=2.2,<3)
Requires-Dist: hyperframe (<5,>=3.1,!=4.0.0)
Requires-Dist: enum34 (>=1.0.4,<2); python_version == "2.7" or python_version == "3.3"

===============================
hyper-h2: HTTP/2 Protocol Stack
===============================

.. image:: https://raw.github.com/Lukasa/hyper/development/docs/source/images/hyper.png

.. image:: https://travis-ci.org/python-hyper/hyper-h2.svg?branch=master
    :target: https://travis-ci.org/python-hyper/hyper-h2

This repository contains a pure-Python implementation of a HTTP/2 protocol
stack. It's written from the ground up to be embeddable in whatever program you
choose to use, ensuring that you can speak HTTP/2 regardless of your
programming paradigm.

You use it like this:

.. code-block:: python

    import h2.connection

    conn = h2.connection.H2Connection()
    conn.send_headers(stream_id=stream_id, headers=headers)
    conn.send_data(stream_id, data)
    socket.sendall(conn.data_to_send())
    events = conn.receive_data(socket_data)

This repository does not provide a parsing layer, a network layer, or any rules
about concurrency. Instead, it's a purely in-memory solution, defined in terms
of data actions and HTTP/2 frames. This is one building block of a full Python
HTTP implementation.

To install it, just run:

.. code-block:: console

    $ pip install h2

Documentation
=============

Documentation is available at http://python-hyper.org/h2/.

Contributing
============

``hyper-h2`` welcomes contributions from anyone! Unlike many other projects we
are happy to accept cosmetic contributions and small contributions, in addition
to large feature requests and changes.

Before you contribute (either by opening an issue or filing a pull request),
please `read the contribution guidelines`_.

.. _read the contribution guidelines: http://python-hyper.org/en/latest/contributing.html

License
=======

``hyper-h2`` is made available under the MIT License. For more details, see the
``LICENSE`` file in the repository.

Authors
=======

``hyper-h2`` is maintained by Cory Benfield, with contributions from others. For
more details about the contributors, please see ``CONTRIBUTORS.rst``.


Release History
===============

2.5.0 (2016-10-25)
------------------

API Changes (Backward-Compatible)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

- Added a new ``H2Configuration`` object that allows rich configuration of
  a ``H2Connection``. This object supersedes the prior keyword arguments to the
  ``H2Connection`` object, which are now deprecated and will be removed in 3.0.
- Added support for automated window management via the
  ``acknowledge_received_data`` method. See the documentation for more details.
- Added a ``DenialOfServiceError`` that is raised whenever a behaviour that
  looks like a DoS attempt is encountered: for example, an overly large
  decompressed header list. This is a subclass of ``ProtocolError``.
- Added support for setting and managing ``SETTINGS_MAX_HEADER_LIST_SIZE``.
  This setting is now defaulted to 64kB.
- Added ``h2.errors.ErrorCodes``, an enum that is used to store all the HTTP/2
  error codes. This allows us to use a better printed representation of the
  error code in most places that it is used.
- The ``error_code`` fields on ``ConnectionTerminated`` and ``StreamReset``
  events have been updated to be instances of ``ErrorCodes`` whenever they
  correspond to a known error code. When they are an unknown error code, they
  are instead ``int``. As ``ErrorCodes`` is a subclass of ``int``, this is
  non-breaking.
- Deprecated the other fields in ``h2.errors``. These will be removed in 3.0.0.

Bugfixes
~~~~~~~~

- Correctly reject request header blocks with neither :authority nor Host
  headers, or header blocks which contain mismatched :authority and Host
  headers, per RFC 7540 Section 8.1.2.3.
- Correctly expect that responses to HEAD requests will have no body regardless
  of the value of the Content-Length header, and reject those that do.
- Correctly refuse to send header blocks that contain neither :authority nor
  Host headers, or header blocks which contain mismatched :authority and Host
  headers, per RFC 7540 Section 8.1.2.3.
- Hyper-h2 will now reject header field names and values that contain leading
  or trailing whitespace.
- Correctly strip leading/trailing whitespace from header field names and
  values.
- Correctly refuse to send header blocks with a TE header whose value is not
  ``trailers``, per RFC 7540 Section 8.1.2.2.
- Correctly refuse to send header blocks with connection-specific headers,
  per RFC 7540 Section 8.1.2.2.
- Correctly refuse to send header blocks that contain duplicate pseudo-header
  fields, or with pseudo-header fields that appear after ordinary header fields,
  per RFC 7540 Section 8.1.2.1.

  This may cause passing a dictionary as the header block to ``send_headers``
  to throw a ``ProtocolError``, because dictionaries are unordered and so they
  may trip this check.  Passing dictionaries here is deprecated, and callers
  should change to using a sequence of 2-tuples as their header blocks.
- Correctly reject trailers that contain HTTP/2 pseudo-header fields, per RFC
  7540 Section 8.1.2.1.
- Correctly refuse to send trailers that contain HTTP/2 pseudo-header fields,
  per RFC 7540 Section 8.1.2.1.
- Correctly reject responses that do not contain the ``:status`` header field,
  per RFC 7540 Section 8.1.2.4.
- Correctly refuse to send responses that do not contain the ``:status`` header
  field, per RFC 7540 Section 8.1.2.4.
- Correctly update the maximum frame size when the user updates the value of
  that setting. Prior to this release, if the user updated the maximum frame
  size hyper-h2 would ignore the update, preventing the remote peer from using
  the higher frame sizes.

2.4.2 (2016-10-25)
------------------

Bugfixes
~~~~~~~~

- Correctly update the maximum frame size when the user updates the value of
  that setting. Prior to this release, if the user updated the maximum frame
  size hyper-h2 would ignore the update, preventing the remote peer from using
  the higher frame sizes.

2.3.3 (2016-10-25)
------------------

Bugfixes
~~~~~~~~

- Correctly update the maximum frame size when the user updates the value of
  that setting. Prior to this release, if the user updated the maximum frame
  size hyper-h2 would ignore the update, preventing the remote peer from using
  the higher frame sizes.

2.2.7 (2016-10-25)
------------------

*Final 2.2.X release*

Bugfixes
~~~~~~~~

- Correctly update the maximum frame size when the user updates the value of
  that setting. Prior to this release, if the user updated the maximum frame
  size hyper-h2 would ignore the update, preventing the remote peer from using
  the higher frame sizes.

2.4.1 (2016-08-23)
------------------

Bugfixes
~~~~~~~~

- Correctly expect that responses to HEAD requests will have no body regardless
  of the value of the Content-Length header, and reject those that do.

2.3.2 (2016-08-23)
------------------

Bugfixes
~~~~~~~~

- Correctly expect that responses to HEAD requests will have no body regardless
  of the value of the Content-Length header, and reject those that do.

2.4.0 (2016-07-01)
------------------

API Changes (Backward-Compatible)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

- Adds ``additional_data`` to ``H2Connection.close_connection``, allowing the
  user to send additional debug data on the GOAWAY frame.
- Adds ``last_stream_id`` to ``H2Connection.close_connection``, allowing the
  user to manually control what the reported last stream ID is.
- Add new method: ``prioritize``.
- Add support for emitting stream priority information when sending headers
  frames using three new keyword arguments: ``priority_weight``,
  ``priority_depends_on``, and ``priority_exclusive``.
- Add support for "related events": events that fire simultaneously on a single
  frame.


2.3.1 (2016-05-12)
------------------

Bugfixes
~~~~~~~~

- Resolved ``AttributeError`` encountered when receiving more than one sequence
  of CONTINUATION frames on a given connection.


2.2.5 (2016-05-12)
------------------

Bugfixes
~~~~~~~~

- Resolved ``AttributeError`` encountered when receiving more than one sequence
  of CONTINUATION frames on a given connection.


2.3.0 (2016-04-26)
------------------

API Changes (Backward-Compatible)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

- Added a new flag to the ``H2Connection`` constructor: ``header_encoding``,
  that controls what encoding is used (if any) to decode the headers from bytes
  to unicode. This defaults to UTF-8 for backward compatibility. To disable the
  decode and use bytes exclusively, set the field to False, None, or the empty
  string. This affects all headers, including those pushed by servers.
- Bumped the minimum version of HPACK allowed from 2.0 to 2.2.
- Added support for advertising RFC 7838 Alternative services.
- Allowed users to provide ``hpack.HeaderTuple`` and
  ``hpack.NeverIndexedHeaderTuple`` objects to all methods that send headers.
- Changed all events that carry headers to emit ``hpack.HeaderTuple`` and
  ``hpack.NeverIndexedHeaderTuple`` instead of plain tuples. This allows users
  to maintain header indexing state.
- Added support for plaintext upgrade with the ``initiate_upgrade_connection``
  method.

Bugfixes
~~~~~~~~

- Automatically ensure that all ``Authorization`` and ``Proxy-Authorization``
  headers, as well as short ``Cookie`` headers, are prevented from being added
  to encoding contexts.

2.2.4 (2016-04-25)
------------------

Bugfixes
~~~~~~~~

- Correctly forbid pseudo-headers that were not defined in RFC 7540.
- Ignore AltSvc frames, rather than exploding when receiving them.

2.1.5 (2016-04-25)
------------------

*Final 2.1.X release*

Bugfixes
~~~~~~~~

- Correctly forbid pseudo-headers that were not defined in RFC 7540.
- Ignore AltSvc frames, rather than exploding when receiving them.

2.2.3 (2016-04-13)
------------------

Bugfixes
~~~~~~~~

- Allowed the 4.X series of hyperframe releases as dependencies.

2.1.4 (2016-04-13)
------------------

Bugfixes
~~~~~~~~

- Allowed the 4.X series of hyperframe releases as dependencies.


2.2.2 (2016-04-05)
------------------

Bugfixes
~~~~~~~~

- Fixed issue where informational responses were erroneously not allowed to be
  sent in the ``HALF_CLOSED_REMOTE`` state.
- Fixed issue where informational responses were erroneously not allowed to be
  received in the ``HALF_CLOSED_LOCAL`` state.
- Fixed issue where we allowed information responses to be sent or received
  after final responses.

2.2.1 (2016-03-23)
------------------

Bugfixes
~~~~~~~~

- Fixed issue where users using locales that did not default to UTF-8 were
  unable to install source distributions of the package.

2.2.0 (2016-03-23)
------------------

API Changes (Backward-Compatible)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

- Added support for sending informational responses (responses with 1XX status)
  codes as part of the standard flow. HTTP/2 allows zero or more informational
  responses with no upper limit: hyper-h2 does too.
- Added support for receiving informational responses (responses with 1XX
  status) codes as part of the standard flow. HTTP/2 allows zero or more
  informational responses with no upper limit: hyper-h2 does too.
- Added a new event: ``ReceivedInformationalResponse``. This response is fired
  when informational responses (those with 1XX status codes).
- Added an ``additional_data`` field to the ``ConnectionTerminated`` event that
  carries any additional data sent on the GOAWAY frame. May be ``None`` if no
  such data was sent.
- Added the ``initial_values`` optional argument to the ``Settings`` object.

Bugfixes
~~~~~~~~

- Correctly reject all of the connection-specific headers mentioned in RFC 7540
  § 8.1.2.2, not just the ``Connection:`` header.
- Defaulted the value of ``SETTINGS_MAX_CONCURRENT_STREAMS`` to 100, unless
  explicitly overridden. This is a safe defensive initial value for this
  setting.

2.1.3 (2016-03-16)
------------------

Deprecations
~~~~~~~~~~~~

- Passing dictionaries to ``send_headers`` as the header block is deprecated,
  and will be removed in 3.0.

2.1.2 (2016-02-17)
------------------

Bugfixes
~~~~~~~~

- Reject attempts to push streams on streams that were themselves pushed:
  streams can only be pushed on streams that were initiated by the client.
- Correctly allow CONTINUATION frames to extend the header block started by a
  PUSH_PROMISE frame.
- Changed our handling of frames received on streams that were reset by the
  user.

  Previously these would, at best, cause ProtocolErrors to be raised and the
  connection to be torn down (rather defeating the point of resetting streams
  at all) and, at worst, would cause subtle inconsistencies in state between
  hyper-h2 and the remote peer that could lead to header block decoding errors
  or flow control blockages.

  Now when the user resets a stream all further frames received on that stream
  are ignored except where they affect some form of connection-level state,
  where they have their effect and are then ignored.
- Fixed a bug whereby receiving a PUSH_PROMISE frame on a stream that was
  closed would cause a RST_STREAM frame to be emitted on the closed-stream,
  but not the newly-pushed one. Now this causes a ``ProtocolError``.

2.1.1 (2016-02-05)
------------------

Bugfixes
~~~~~~~~

- Added debug representations for all events.
- Fixed problems with setup.py that caused trouble on older setuptools/pip
  installs.

2.1.0 (2016-02-02)
------------------

API Changes (Backward-Compatible)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

- Added new field to ``DataReceived``: ``flow_controlled_length``. This is the
  length of the frame including padded data, allowing users to correctly track
  changes to the flow control window.
- Defined new ``UnsupportedFrameError``, thrown when frames that are known to
  hyperframe but not supported by hyper-h2 are received. For
  backward-compatibility reasons, this is a ``ProtocolError`` *and* a
  ``KeyError``.

Bugfixes
~~~~~~~~

- Hyper-h2 now correctly accounts for padding when maintaining flow control
  windows.
- Resolved a bug where hyper-h2 would mistakenly apply
  SETTINGS_INITIAL_WINDOW_SIZE to the connection flow control window in
  addition to the stream-level flow control windows.
- Invalid Content-Length headers now throw ``ProtocolError`` exceptions and
  correctly tear the connection down, instead of leaving the connection in an
  indeterminate state.
- Invalid header blocks now throw ``ProtocolError``, rather than a grab bag of
  possible other exceptions.

2.0.0 (2016-01-25)
------------------

API Changes (Breaking)
~~~~~~~~~~~~~~~~~~~~~~

- Attempts to open streams with invalid stream IDs, either by the remote peer
  or by the user, are now rejected as a ``ProtocolError``. Previously these
  were allowed, and would cause remote peers to error.
- Receiving frames that have invalid padding now causes the connection to be
  terminated with a ``ProtocolError`` being raised. Previously these passed
  undetected.
- Settings values set by both the user and the remote peer are now validated
  when they're set. If they're invalid, a new ``InvalidSettingsValueError`` is
  raised and, if set by the remote peer, a connection error is signaled.
  Previously, it was possible to set invalid values. These would either be
  caught when building frames, or would be allowed to stand.
- Settings changes no longer require user action to be acknowledged: hyper-h2
  acknowledges them automatically. This moves the location where some
  exceptions may be thrown, and also causes the ``acknowledge_settings`` method
  to be removed from the public API.
- Removed a number of methods on the ``H2Connection`` object from the public,
  semantically versioned API, by renaming them to have leading underscores.
  Specifically, removed:

    - ``get_stream_by_id``
    - ``get_or_create_stream``
    - ``begin_new_stream``
    - ``receive_frame``
    - ``acknowledge_settings``

- Added full support for receiving CONTINUATION frames, including policing
  logic about when and how they are received. Previously, receiving
  CONTINUATION frames was not supported and would throw exceptions.
- All public API functions on ``H2Connection`` except for ``receive_data`` no
  longer return lists of events, because these lists were always empty. Events
  are now only raised by ``receive_data``.
- Calls to ``increment_flow_control_window`` with out of range values now raise
  ``ValueError`` exceptions. Previously they would be allowed, or would cause
  errors when serializing frames.

API Changes (Backward-Compatible)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

- Added ``PriorityUpdated`` event for signaling priority changes.
- Added ``get_next_available_stream_id`` function.
- Receiving DATA frames on streams not in the OPEN or HALF_CLOSED_LOCAL states
  now causes a stream reset, rather than a connection reset. The error is now
  also classified as a ``StreamClosedError``, rather than a more generic
  ``ProtocolError``.
- Receiving HEADERS or PUSH_PROMISE frames in the HALF_CLOSED_REMOTE state now
  causes a stream reset, rather than a connection reset.
- Receiving frames that violate the max frame size now causes connection errors
  with error code FRAME_SIZE_ERROR, not a generic PROTOCOL_ERROR. This
  condition now also raises a ``FrameTooLargeError``, a new subclass of
  ``ProtocolError``.
- Made ``NoSuchStreamError`` a subclass of ``ProtocolError``.
- The ``StreamReset`` event is now also fired whenever a protocol error from
  the remote peer forces a stream to close early. This is only fired once.
- The ``StreamReset`` event now carries a flag, ``remote_reset``, that is set
  to ``True`` in all cases where ``StreamReset`` would previously have fired
  (e.g. when the remote peer sent a RST_STREAM), and is set to ``False`` when
  it fires because the remote peer made a protocol error.
- Hyper-h2 now rejects attempts by peers to increment a flow control window by
  zero bytes.
- Hyper-h2 now rejects peers sending header blocks that are ill-formed for a
  number of reasons as set out in RFC 7540 Section 8.1.2.
- Attempting to send non-PRIORITY frames on closed streams now raises
  ``StreamClosedError``.
- Remote peers attempting to increase the flow control window beyond
  ``2**31 - 1``, either by window increment or by settings frame, are now
  rejected as ``ProtocolError``.
- Local attempts to increase the flow control window beyond ``2**31 - 1`` by
  window increment are now rejected as ``ProtocolError``.
- The bytes that represent individual settings are now available in
  ``h2.settings``, instead of needing users to import them from hyperframe.

Bugfixes
~~~~~~~~

- RFC 7540 requires that a separate minimum stream ID be used for inbound and
  outbound streams. Hyper-h2 now obeys this requirement.
- Hyper-h2 now does a better job of reporting the last stream ID it has
  partially handled when terminating connections.
- Fixed an error in the arguments of ``StreamIDTooLowError``.
- Prevent ``ValueError`` leaking from Hyperframe.
- Prevent ``struct.error`` and ``InvalidFrameError`` leaking from Hyperframe.

1.1.1 (2015-11-17)
------------------

Bugfixes
~~~~~~~~

- Forcibly lowercase all header names to improve compatibility with
  implementations that demand lower-case header names.

1.1.0 (2015-10-28)
------------------

API Changes (Backward-Compatible)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

- Added a new ``ConnectionTerminated`` event, which fires when GOAWAY frames
  are received.
- Added a subclass of ``NoSuchStreamError``, called ``StreamClosedError``, that
  fires when actions are taken on a stream that is closed and has had its state
  flushed from the system.
- Added ``StreamIDTooLowError``, raised when the user or the remote peer
  attempts to create a stream with an ID lower than one previously used in the
  dialog. Inherits from ``ValueError`` for backward-compatibility reasons.

Bugfixes
~~~~~~~~

- Do not throw ``ProtocolError`` when attempting to send multiple GOAWAY
  frames on one connection.
- We no longer forcefully change the decoder table size when settings changes
  are ACKed, instead waiting for remote acknowledgement of the change.
- Improve the performance of checking whether a stream is open.
- We now attempt to lazily garbage collect closed streams, to avoid having the
  state hang around indefinitely, leaking memory.
- Avoid further per-stream allocations, leading to substantial performance
  improvements when many short-lived streams are used.

1.0.0 (2015-10-15)
------------------

- First production release!