pyley 0.2.1



pyley [](https://travis-ci.org/ziyasal/pyley) [](https://coveralls.io/github/ziyasal/pyley?branch=master)
=====

[Python](https://www.python.org/) client for an open-source graph database [**Cayley**](https://github.com/google/cayley)

> Cayley is an open-source graph inspired by the graph database behind [Freebase](http://freebase.com/) and Google's [Knowledge Graph](http://www.google.com/insidesearch/features/search/knowledge.html). Its goal is to be a part of the developer's toolbox where [Linked Data](http://linkeddata.org/) and graph-shaped data (semantic webs, social networks, etc) in general are concerned.

**Install via pip**

```
pip install pyley
```

##Sample

```python
#Create cayley client
client = CayleyClient() # this creates client with default parameters `http://localhost:64210/api/v1/query/gremlin`
#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.
g.Vertex().GetLimit(5)

#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") \
.All()

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") \
.All()
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)
```

##Bugs
If you encounter a bug, performance issue, or malfunction, please add an [Issue](https://github.com/ziyasal/pyley/issues) with steps on how to reproduce the problem.

##TODO
- Improve Gremlin implementation (Basic steps implemented at the moment)
- Add more tests
- Add more documentation

##Open Source Projects in Use
- [requests](https://github.com/kennethreitz/requests) by @kennethreitz

##License

Code and documentation are available according to the *MIT* License (see [LICENSE](https://github.com/ziyasal/pyley/blob/master/LICENSE)).