CID (Content IDentifier)

.. image:: https://img.shields.io/pypi/v/py-multiformats-cid.svg :target: https://pypi.python.org/pypi/py-multiformats-cid

What is CID ?

CID <https://github.com/multiformats/cid> is a format for referencing content in distributed information systems, like IPFS <https://ipfs.io>. It leverages content addressing <https://en.wikipedia.org/wiki/Content-addressable_storage>_, cryptographic hashing <https://simple.wikipedia.org/wiki/Cryptographic_hash_function>, and self-describing formats <https://github.com/multiformats/multiformats>.

It is the core identifier used by IPFS <https://ipfs.io> and IPLD <https://ipld.io>.

CID is a self-describing content-addressed identifier.

It uses cryptographic hashes to achieve content addressing.

It uses several multiformats <https://github.com/multiformats/multiformats> to achieve flexible self-description, namely multihash <https://github.com/multiformats/multihash> for hashes, multicodec <https://github.com/multiformats/multicodec> for data content types, and multibase <https://github.com/multiformats/multibase> to encode the CID itself into strings.

Sample Usage

.. code-block:: python

>>> from multiformats_cid import make_cid
>>> make_cid('QmaozNR7DZHQK1ZcU9p7QdrshMvXqWK6gpu5rmrkPdT3L4')
CIDv0(version=0, codec=dag-pb, multihash=b"\x12 \xb9M'\xb9\x93M>\x08\xa5.R\xd7\xda}\xab\xfa\xc4\x84..")

>>> cid = make_cid('QmaozNR7DZHQK1ZcU9p7QdrshMvXqWK6gpu5rmrkPdT3L4')
>>> print(cid.version, cid.codec, cid.multihash)

>>> print(cid.encode())
QmaozNR7DZHQK1ZcU9p7QdrshMvXqWK6gpu5rmrkPdT3L4

>>> str(cid)
'QmaozNR7DZHQK1ZcU9p7QdrshMvXqWK6gpu5rmrkPdT3L4'

Installation

Stable release

To install *py-multiformats-cid*, run this command in your terminal:

.. code-block:: console

    $ pip install py-multiformats-cid

This is the preferred method to install CID, as it will always install the most recent stable release.

If you don't have `pip`_ installed, this `Python installation guide`_ can guide
you through the process.

.. _pip: https://pip.pypa.io
.. _Python installation guide: http://docs.python-guide.org/en/latest/starting/installation/

From sources

The sources for py-multiformats-cid can be downloaded from the Github repo_.

You can either clone the public repository:

.. code-block:: console

$ git clone https://github.com/pinnaculum/py-multiformats-cid

Or download the tarball_:

.. code-block:: console

$ curl  -OL https://github.com/pinnaculum/py-multiformats-cid/tarball/master

Once you have a copy of the source, you can install it with:

.. code-block:: console

$ python setup.py install

.. _Github repo: https://github.com/pinnaculum/py-multiformats-cid .. _tarball: https://github.com/pinnaculum/py-multiformats-cid/tarball/master

Other info

• Free software: MIT license
• Documentation: https://py-multiformats-cid.readthedocs.io.
• Python versions: 3.7, 3.8, 3.9, 3.10