Universal Graph Interface for Python
Project description
Graphs for Python
Copyright/License
All content copyright 2017 Aaron M. Hosford. Use of this software is governed by the MIT license. See LICENSE.txt for the full license agreement.
Package Structure
test_vert: Unit tests for vert
test_stores: Unit tests for vert.stores
__init__.py: Empty placeholder.
_base.py: Contains base class for vert.stores test cases.
test_dbm.py: Unit tests for vert.stores.dbm.
test_memory.py: Unit tests for vert.stores.memory.
__init__.py: Empty placeholder.
vert: The package root
stores: Subpackage containing implementations of various graph stores that the vert package supports out of the box.
__init__.py: Empty placeholder.
base.py: Defines the GraphStore interface that all graph stores have to implement. The GraphStore interface hides the implementation details for each graph store, providing a consistent, albeit clunky, means of accessing and modifying the contents of a graph.
dbm.py: Defines DBMGraphStore, a DBM-backed persistent graph store.
memory.py: Defines the MemoryGraphStore, a non-persistent, memory-only graph store.
__init__.py: Exports the publicly visible symbols for the vert package. Nothing is actually defined in this module.
graphs.py: Defines the Graph, Vertex, and Edge, classes, along with other supporting infrastructure. This module’s classes transform the clunky interface provided by GraphStore into a convenient and versatile object-oriented interface designed to make it easy to work with graphs in a consistent manner regardless of how the underlying storage mechanisms work.
Examples
Non-Persistent
from vert import Graph with Graph() as g: dog = g.vertices['dog'].add() cat = g.vertices['cat'].add() edge = g.edges['dog', 'cat'] print(edge.exists) # False edge.add() print(edge.exists) # True edge.labels.add('chases') print('chases' in edge.labels) # True with Graph() as g: edge = g.edges['dog', 'cat'] print(edge.exists) # False
DBM-Backed Persistence
from vert import Graph with Graph('test.db') as g: dog = g.vertices['dog'].add() cat = g.vertices['cat'].add() edge = g.edges['dog', 'cat'] print(edge.exists) # False edge.add() print(edge.exists) # True edge.labels.add('chases') print('chases' in edge.labels) # True with Graph('test.db') as g: edge = g.edges['dog', 'cat'] print(edge.exists) # Still true print('chases' in edge.labels) # Still true
Defining Your Own Storage Mechanism
from vert import Graph, GraphStore class MyGraphStore(GraphStore): # Implement each of GraphStore's abstract methods here ... with Graph(MyGraphStore(...)) as g: # Now the graph consults your back end for storage and retrieval ...
TODO:
Add separately installable graph stores for neo4j, tinkerpop, networkx, sqlite, and other back ends.
Add an example for creating a third-party module to provide support for new kinds of graph stores.
Add algorithms such as path finding and pattern matching. Whenever possible, these should be implemented by the graph store, rather than at the interface level. By having the interface classes inspect the graph store for the method before calling it, it should be possible to fall back on a slower default client-side implementation when the store does not provide one. An alternate approach would be to add the methods to the GraphStore class but have them raise a special sentinel exception if the particular implementation doesn’t provide the algorithm.
Add support for transactions and make the code thread-safe.
Add support for reading & writing common graph file formats.
Add support for transferring from one graph store to another.
100% code coverage for unit testing.
Prettify the string representations for Edges and Vertices.
Make the DBM graph store more efficient.
Add proper documentation strings.
Add an intro to the README file.
Support older versions of Python.
Project details
Release history Release notifications | RSS feed
Download files
Download the file for your platform. If you're not sure which to choose, learn more about installing packages.