CBOR (de)serializer with extensive tag support

Warnings

• breaking The modules `cbor2.encoder`, `cbor2.decoder`, and `cbor2.types` have been deprecated since version 5.5.0 and will be removed in the upcoming 6.x.x major release. Direct imports from these modules will cause `ModuleNotFoundError`.
  Fix: Update imports to load symbols directly from the `cbor2` package (e.g., `from cbor2 import dumps` instead of `from cbor2.encoder import dumps`).
• breaking Version 6.0.0 (currently in release candidate) introduces several backward-incompatible changes, including signature changes for `tag_hook` and `object_hook` decoder callables, removal of `break_marker`, changes in IP address encoding tags, and removal of individual decoding functions from the API.
  Fix: Review the official `cbor2` documentation for version 6.0.0 for a complete list of breaking changes and adapt custom `tag_hook` and `object_hook` implementations. Avoid direct calls to previously available individual decoding functions.
• gotcha When encoding Python objects with cyclic references (e.g., lists or dictionaries that refer back to themselves), `cbor2` will raise a `CBOREncodeError` by default. CBOR supports shared value references as an extension.
  Fix: To encode cyclic data structures, enable value sharing by passing `value_sharing=True` to `cbor2.dumps()` or `cbor2.dump()`. Be aware that support for value sharing may be rare in other CBOR implementations.
• gotcha When using `CBOREncoder` or `CBORWriter` for streaming (e.g., writing to a file), forgetting to call `close()` can result in truncated or incomplete CBOR data. The `with` statement handles this automatically.
  Fix: Always ensure the encoder or writer is properly closed, either explicitly with `writer.close()` or by using a `with` statement.
• gotcha Decoding malformed or corrupted CBOR data with `cbor2.loads()` or `cbor2.load()` will raise a `cbor2.CBORDecodeError`, potentially crashing the application if not handled.
  Fix: Wrap deserialization calls in a `try-except cbor2.CBORDecodeError` block to gracefully handle potential decoding issues and ensure application stability.
• gotcha When decoding CBOR, a value that appears simple (like a string or integer) might actually be a CBOR-tagged type (e.g., a `datetime` object for a timestamp tag). If your code expects a specific simple Python type, this can lead to runtime errors.
  Fix: Always verify the type of decoded data, especially when dealing with potentially tagged values, and be prepared to handle the appropriate Python object types that `cbor2` maps to standard CBOR tags.

Install

• pip install cbor2 Install stable version

Imports

• dumps

  from cbor2 import dumps

• loads

  from cbor2 import loads

• dump

  from cbor2 import dump

• load

  from cbor2 import load

• CBOREncoder

  from cbor2 import CBOREncoder

  The `cbor2.encoder` module was deprecated in 5.5.0 and will be removed in the next major release (6.x.x). Import directly from `cbor2` instead.
• CBORDecoder

  from cbor2 import CBORDecoder

  The `cbor2.decoder` module was deprecated in 5.5.0 and will be removed in the next major release (6.x.x). Import directly from `cbor2` instead.

Quickstart

This quickstart demonstrates the basic encoding and decoding of Python objects to and from CBOR bytestrings using `cbor2.dumps()` and `cbor2.loads()`.

import cbor2

data_to_encode = {'name': 'Alice', 'age': 30, 'is_active': True}

# Encode Python object to CBOR bytestring
encoded_data = cbor2.dumps(data_to_encode)
print(f"Encoded CBOR: {encoded_data}")

# Decode CBOR bytestring back to Python object
decoded_data = cbor2.loads(encoded_data)
print(f"Decoded Python object: {decoded_data}")

# Example with file-like objects
# import io
# output_buffer = io.BytesIO()
# cbor2.dump(data_to_encode, output_buffer)
# output_buffer.seek(0)
# decoded_from_file = cbor2.load(output_buffer)
# print(f"Decoded from file-like object: {decoded_from_file}")