This library provides encoding and decoding for the Concise Binary Object Representation (CBOR)
(`RFC 8949`_) serialization format. The specification is fully compatible with the original RFC 7049.
`Read the docs <https://cbor2.readthedocs.io/>`_ to learn more.
It is implemented in pure python with an optional C backend.
On PyPy, cbor2 runs with almost identical performance to the C backend.
* Simple api like ``json`` or ``pickle`` modules.
* Support many `CBOR tags`_ with `stdlib objects`_.
* Generic tag decoding.
* `Shared value`_ references including cyclic references.
* `String references`_ compact encoding with repeated strings replaced with indices.
* Optional C module backend tested on big- and little-endian architectures.
* Extensible `tagged value handling`_ using ``tag_hook`` and ``object_hook`` on decode and ``default`` on encode.
* Command-line diagnostic tool, converting CBOR file or stream to JSON ``python -m cbor2.tool``
(This is a lossy conversion, for diagnostics only)
* Thorough test suite.
* Python >= 3.9 (or `PyPy3`_ 3.9+)
* C-extension: Any C compiler that can build Python extensions.
Any modern libc with the exception of Glibc<2.9
.. _PyPy3: https://www.pypy.org/
Building the C-Extension
------------------------
To force building of the optional C-extension, set OS env ``CBOR2_BUILD_C_EXTENSION=1``.
To disable building of the optional C-extension, set OS env ``CBOR2_BUILD_C_EXTENSION=0``. If this environment variable is unset, setup.py will default to auto detecting a compatible C library and
attempt to compile the extension.
The provided command line tool (``cbor2``) converts CBOR data in raw binary or base64
encoding into a representation that allows printing as JSON. This is a lossy
transformation as each datatype is converted into something that can be represented as a
JSON value.
The tool can alternatively be invoked with ``python -m cbor2.tool``.
This library has not been tested against malicious input. In theory it should be as safe as JSON, since unlike ``pickle`` the decoder does not execute any code.
Messung V0.5 in Prozent
[Dauer der Verarbeitung: 0.19 Sekunden, vorverarbeitet 2026-08-25]