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astro-stan/pyitc

pyitc

Build Status Latest GitHub Release License AGPL-3.0

Python bindings for the libitc library.

Table Of Contents

What Are Interval Tree Clocks?

Interval Tree Clocks (ITC) are a generalisation of the Vector Clock and Version Vector mechanisms, allowing for scalable and efficient management of a highly dynamic number of replicas/processes in a distributed system.

See the ITC research paper from Paulo Sérgio Almeida, Carlos Baquero and Victor Fonte for more information.

Features

  • Provides easy-to-use, Pythonesque bindings for the underlying C library
  • Provides __str__ methods for easy visualisation of the ITC trees
  • Provides bindings for the C lib's "extended API"
  • Uses 64-bit event counters

Getting Started

Prerequisites

Download and install the wheels/sdist from PyPI or GitHub.

Usage Examples

Here are some usage examples:

from pyitc import Stamp, StampComparisonResult
from pyitc.extended_api import Id, Event

stamp = Stamp()
stamp.event()

stamp2 = stamp.fork()

print(stamp) # {(0, 1); 1}
print(stamp.peek()) # {0, 1}
print(stamp2) # {(1, 0); 1}

if stamp == stamp2: # all comparision operators are supported
    print("yay!")
else:
    print("nay")

if stamp.compare_to(stamp2) == StampComparisonResult.EQUAL: # equivalent to stamp == stamp2
    print("yay again!")

stamp2.event() # Make stamp2 concurrent with stamp

if stamp.compare_to(stamp2) == StampComparisonResult.CONCURRENT:
    print("Oh no! What should we do now?")

stamp3 = stamp2.fork()

stamp2.join(stamp3)

if not stamp3.is_valid():
    print("stamp3 was joined with stamp2 and is no longer valid!")

print(stamp.id_component) # (0, 1)
print(stamp.event_component) # 1

stamp.event_component = Event()
stamp.id_component = Id(seed=True)

print(stamp.serialise()) # b'\x01\t\x01\x02\x01\x00'
print(stamp.id_component.serialise()) # b'\x01\x02'
print(stamp.event_component.serialise()) # b'\x01\x00'

remote_stamp = Stamp.deserialise(b'...')
remote_event = Event.deserialise(b'...')
remote_id = Id.deserialise(b'...')

Contributing

See CONTRIBUTING.md.

Reporting Vulnerabilities

⚠️ NEVER open public issues or pull requests to report or fix security vulnerabilities.

See the Security Policy.