graphcache

Python Library to store connected nodes and their properties on cache storage (redis)

Installation

To install graphcache:

pip install graphcache

Development

• Install pyenv and pyenv-virtualenv
• Run

  pyenv install 3.7.0 --skip-existing
  pyenv virtualenv 3.7.0 graphcache
  

• Update requirements

  pip install -r requirements.txt
  

• Install Redis

Basic Use

Ensure you have redis service running
On macos

redis-server /usr/local/etc/redis.conf

To use graphcache,
first create an instance of GraphCache and construct your nodes and edges:

# Import GraphCache
from graphcache import GraphCache

# default 
# host = localhost
# port = 6379
# db = 0
g = GraphCache(host='localhost', port=6379, db=0)

# Add optimisation keys
g.optimise_for('bananas')
g.optimise_for('apples')

# Create Nodes (need 'apples', 'bananas' keys in all nodes, as they have been added to optimisation_keys)
n1 = g.add_vertex({
    'name': 'Tom',
    'age': 24,
    'bananas': 5,
    'apples': 4
})
n2 = g.add_vertex({
    'name': 'Bob',
    'bananas': 0,
    'apples': 8
})
n3 = g.add_vertex({
    'name': 'Harry',
    'gender': 'Male',
    'bananas': 3,
    'apples': 1
})
n4 = g.add_vertex({
    'name': 'Jill',
    'bananas': 8,
    'apples': 1
})

# Connect them
g.add_edge(g.entry, n2) # g.entry specifies the entry point for graph
g.add_edge(g.entry, n3)
g.add_edge(n2, n3)
g.add_edge(n3, n4)
g.add_edge(n2, n1)

Now you can perform filter/sort operations on any of the node to get the required adjacent nodes from that node:

# Filter By
# Get all outgoing nodes (only adjacent) from n2 which have only 1 apples
nodes1 = n2.get_outgoing().filter_by('apples', [1]).get_all_nodes()

# Sort By
# Get all incoming nodes (only adjacent) to n3 sorted by number of bananas they have
nodes2 = n3.get_incoming().sort_by('bananas').get_all_nodes()

# Get first incoming node to n1 sorted by bananas
node1 = n1.get_incoming().sort_by('bananas').get_node_indexed_at(0)

Also you can perform chained operations:

# Filter By, Sort By
# Get all outgoing nodes (only adjacent) from n2 with apples less than 5 and sorted by bananas
nodes1 = n2.get_outgoing().filter_by('apples', 5, "lt").sort_by('bananas').get_all_nodes()

# Sort By, Filter By, Filter By
nodes2 = n3.get_incoming().sort_by('bananas').filter_by('bananas', [1, 5], "in").filter_by('apples', [1]).get_all_nodes()

Get the key for the graphcache object

g.cache_key
# graphcache-MZ5SQR

Retrieve previously stored graphcache object from redis cache (cache_key = graphcache-MZ5SQR)

# using default redis connection
# host = localhost
# port = 6379
# db = 0
g1 = GraphCache(graphcache_ref='graphcache-MZ5SQR')