Python client for an open-source graph database Cayley

graph, database, cayley, python, client, graph-database
pip install pyley==



Python client for an open-source graph database Cayley

Cayley is an open-source graph inspired by the graph database behind Freebase and Google's Knowledge Graph. Its goal is to be a part of the developer's toolbox where Linked Data and graph-shaped data (semantic webs, social networks, etc) in general are concerned.

Install via pip

You can install pyley using:

$ pip install pyley


Import pyley:

from pyley import CayleyClient, GraphObject

# Create cayley client
# this creates client with default parameters `http://localhost:64210/api/v1/query/gizmo`
client = CayleyClient()

# or  specify `url` and `version` parameters
client = CayleyClient("http://localhost:64210", "v1")

g = GraphObject()

# Query all vertices in the graph, limit to the first 5 vertices found.

# Start with only one vertex, the literal name "Humphrey Bogart", and retrieve all of them.
query = g.Vertex("Humphrey Bogart").All();
response = client.Send(query)
# response.result contains JSON data and response.r contains raw response
print response.result

# `g` and `V` are synonyms for `graph` and `Vertex` respectively, as they are quite common.
query = g.V("Humphrey Bogart").All()
response = client.Send(query)

# "Humphrey Bogart" is a name, but not an entity.
# Let's find the entities with this name in our dataset.
# Follow links that are pointing In to our "Humphrey Bogart" node with the predicate "name".
query = g.V("Humphrey Bogart").In("<name>").All()
response = client.Send(query)

# Notice that "name" is a generic predicate in our dataset.
# Starting with a movie gives a similar effect.
query = g.V("Casablanca").In("name").All()
response = client.Send(query)

# Relatedly, we can ask the reverse; all ids with the name "Casablanca"
query = g.V().Has("name", "Casablanca").All()
response = client.Send(query)

# Let's get the list of actors in the film
query = g.V().Has("name", "Casablanca") \
              .Out("/film/film/starring") \
              .Out("/film/performance/actor") \
              .Out("name") \

response = client.Send(query)

# But this is starting to get long.
# Let's use a morphism -- a pre-defined path stored in a variable -- as our linkage
film_to_actor = g.Morphism().Out("/film/film/starring").Out("/film/performance/actor")
query = g.V() \
        .Has("name", "Casablanca") \
        .Follow(film_to_actor) \
        .Out("name") \
response = client.Send(query)

# Add data programatically to the JSON result list. Can be any JSON type.
query = g.Emit({'name': "John Doe", 'age': 41, 'isActor': True})
response = client.Send(query)


If you encounter a bug, performance issue, or malfunction, please add an Issues with steps on how to reproduce the problem or feel to free to open a pull request.


  • Improve Gizmo implementation (Basic steps implemented at the moment)
  • Add more tests
  • Add more documentation

Open Source Projects in Use


@ziλasal & @abdullahselek