动态格林姆林遍历构造

Question

I'm migrating from the deprecated gremlin-javascript to the new Tinkerpop gremlin .

gremlin-javascript supported an execute method that would take an arbitrary string as a traversal. We could dynamically create and pass this string, such as chaining an arbitrary number of property traversals on a vertex.

Is there a way to dynamically build traversals in the gremlin js client?

Answer 1

For all language variants of Gremlin (Java, JS, Python, etc), you write Gremlin by constructing a Traversal object. You have a g which is a GraphTraversalSource which spawns those Traversal objects and thus:

var t = g.V().values('names');

does not yield a result (ie a list of "name" values) in t but a Traversal object. To get the result you need to iterate the traversal as for example:

t.toList().then(names => console.log(names));

So, if you have a Traversal object that is not yet iterated you can continue to add to it:

var t = g.V().values('names');
t = t.limit(1);
t.next().then(...)