Cayley：如何设置极限/深度以在Cayley中显示图形层次结构？

Question

I need help to limit the nodes to show the graph hierarchy in cayley. Like in OrientDB we have a depth function to restrict the hierarchy to any level up to same level down.

Example: I have a below hierarchy:

A DependsOn B    
B RunsOn C    
C DependsOn D    
D ConnectedTo E    

Now, for the above example I have written a below query to show the graph hierarchy.

var path = g.M().Both();    
g.V("B").FollowRecursive(path).ForEach( function(v) {  
    g.V(v.id).OutPredicates().ForEach( function(r){    
        g.V(v.id).Out().ForEach(function(t){    
            var node = {    
                source: v.id,    
                relation : r.id    
                target: t.id    
            }    
            g.Emit(node)
        })
    }
})

So, when I am passing B to the query it will return me the complete hierarchy but I want only A ,B & C nodes to show for 1 level hierarchy from B, same thing for 2 level hierarchy I want to show A,B,C & D as it should show 2 level up and 2 level down from the B node.

Answer 1

You can limit the depth by passing the max depth as second parameter to the FollowRecursive function:

g.V("B").FollowRecursive(path,2 )

Please not that you start a new path in the foreach which does not know about the max depth in the outer function.

A more detailed discussing about this use-case can be found at the 'cross-post' on the official Cayley forum: https://discourse.cayley.io/t/cayley-0-7-0-depth-function-issue/1066