Jose Mendes has an introduction to the Cosmos DB graph engine:
Gremlin is the graph traversal language of Apache TinkerPop, an open source Graph Computing Framework. Gremlin allows the users to write complex queries to traverse their graphs by using a composed sequence of steps, with each step performing an operation on the data stream (further details here). There are 4 fundamental steps:
· transform: transform the objects in the stream
· filter: remove objects from the stream
· sideEffect: pass the object, but yield some side effect
· branch: decide which step to take
Click through for a quick example showing how to create and populate a graph.