gistfile1.groovy

@ExtensionNaming(namespace = "core", name = "getPathTagCloud")
class GetPathTagCloudExtension extends AbstractRexsterExtension {

    static {
        Gremlin.load();
    }

    @ExtensionDefinition(extensionPoint = ExtensionPoint.GRAPH, method = HttpMethod.POST)
    @ExtensionDescriptor(description = "Generate a keyword distribution of a path")
    public ExtensionResponse evaluate(@RexsterContext RexsterResourceContext context,
                                      @RexsterContext Graph g) {


        try {
            final JSONObject request = context.getRequestObject();

            Vertex source = g.V('uri',request.getString('source_uri')).next()
            Vertex target = g.V('uri',request.getString('target_uri')).next()
            int maxTraversals = request.has(Tokens.MAX_TRAVERSALS) ? request.getInt(Tokens.MAX_TRAVERSALS) : 500;
            final String keywordProperty = request.getString(Tokens.KEYWORD_PROPERTY);

            def m = [:];
            def c = 0;
            source.out(Tokens.AUTHORED).in(Tokens.AUTHORED).loop(2) { c++ < maxTraversals & it.object != target }.has('id', target.getId()).simplePath.path { null } {
                it.out(Tokens.KEYWORD).property(keywordProperty).groupCount(m).iterate()
            }.next(15)
            JSONObject result = new JSONObject();
            result.put(Tokens.TAG_CLOUD, m);
            return ExtensionResponse.ok(result);

        } catch (Exception e) {
            return ExtensionResponse.error(e.getMessage(), e);
        }
    }
}