Support REST Traversal API

[dkushner]

Neo4j has an excellent REST API module that supports custom graph traversals and path aggregation. It would be great if node-neo4j could expose some access to this functionality, preferably via a method with the following specifications:

GraphDatabase.traverse({
    type: 'node' | 'relationship' | 'path' | 'fullpath',
    order: 'breadthFirst' | 'depthFirst',
    relationships: [{
        direction: 'all' | 'in' | 'out',
        type: STRING
    }, {...}],
    uniqueness: 'nodeGlobal' | 'none' | 'relationshipGlobal' | 'nodePath' | 'relationshipPath',
    pruneEvaluator: FUNCTION,
    returnFilter: FUNCTION | 'all' | 'allButStartNode',
    maxDepth: INTEGER
}, function(err, res) {});

Just an idea, based on the documentation here.

[aseemk]

Sorry for the delay in responding here, @dkushner! Thanks for submitting your PR, I'll review it.

Just for curiosity, any reason you prefer the traversal API over Cypher? That's the reason we never bothered implementing this — because Cypher lets you do this in such a nicer way.

(We did implement the simple/convenience getRelationshipNodes method before Cypher was added.)

[hackintoshrao]

Using Cypher for Standard graph traversals like DFS,BFS makes the understanding of these algorithms as bottleneck to execute it . This reduces the usability of the module . It shouldnt be a necessity to understand these standard algorithms to be able to execute them .

[aseemk]

Good point, @Karthic-Hackintosh! Out of curiosity, are you using this traversal API yourself?

[hackintoshrao]

Currently i'm not , but i want contribute to this repo . May be i can start with fixing this up first !!Need some help on starting to contribute to this repo !

[aseemk]

Good news: it's now possible to use the traversal API in node-neo4j v2, even though it's not implemented directly, because you can now make arbitrary & custom HTTP / REST API calls (issue #100).

https://github.com/thingdom/node-neo4j/tree/v2#http--plugins

So I'm going to go ahead mark this issue as fixed in v2. Let me know if you have any q's!