python-omemo

A Python implementation of the OMEMO Multi-End Message and Object Encryption protocol.

A complete implementation of XEP-0384 on protocol-level, i.e. more than just the cryptography. python-omemo supports different versions of the specification through so-called backends. One backend for OMEMO in the urn:xmpp:omemo:2 namespace is shipped with python-omemo. A backend for (legacy) OMEMO in the eu.siacs.conversations.axolotl namespace is available as a separate package: python-omemo-backend-legacy. Multiple backends can be loaded and used at the same time, the library manages their coexistence transparently.

Installation

python-omemo depends on two system libraries, libxeddsa>=2,<3 and libsodium.

Install the latest release using pip (pip install OMEMO) or manually from source by running pip install . (recommended) or python setup.py install in the cloned repository. The installation requires libsodium and the Python development headers to be installed. If a locally installed version of libxeddsa is available, python-xeddsa (a dependency of python-omemo) tries to use that. Otherwise it uses prebuilt binaries of the library, which are available for Linux, MacOS and Windows for the amd64 architecture. Set the LIBXEDDSA_FORCE_LOCAL environment variable to forbid the usage of prebuilt binaries.

Testing, Type Checks and Linting

python-omemo uses pytest as its testing framework, mypy for static type checks and both pylint and Flake8 for linting. All tests/checks can be run locally with the following commands:

$ pip install pytest pytest-asyncio mypy pylint flake8
$ mypy --strict --disable-error-code str-bytes-safe omemo/ setup.py tests/
$ pylint omemo/ setup.py tests/
$ flake8 omemo/ setup.py tests/
$ pytest

Getting Started

Refer to the documentation on readthedocs.io, or build/view it locally in the docs/ directory. To build the docs locally, install the requirements listed in docs/requirements.txt, e.g. using pip install -r docs/requirements.txt, and then run make html from within the docs/ directory. The documentation can then be found in docs/_build/html/.

The functionality.md file contains an overview of supported functionality/use cases, mostly targeted at developers.