Neo4j comes with a number of built-in graph algorithms. They are performed from a start node. The traversal is controlled by the URI and the body sent with the request.
The algorithm to choose. If not set, default is shortestPath
.
algorithm
can have one of these values:
shortestPath
allSimplePaths
allPaths
dijkstra
(optional with cost_property
and default_cost
parameters)
1
.
The shortestPath
algorithm can find multiple paths between the same
nodes, like in this example.
Example request
POST
http://localhost:7474/db/data/node/7/paths
Accept:
application/json
Content-Type:
application/json
{ "to":"http://localhost:7474/db/data/node/2", "max_depth":3, "relationships":{ "type":"to", "direction":"out" }, "algorithm":"shortestPath" }
Example response
200:
OK
Content-Type:
application/json
[ { "start" : "http://localhost:7474/db/data/node/7", "nodes" : [ "http://localhost:7474/db/data/node/7", "http://localhost:7474/db/data/node/3", "http://localhost:7474/db/data/node/2" ], "length" : 2, "relationships" : [ "http://localhost:7474/db/data/relationship/1", "http://localhost:7474/db/data/relationship/7" ], "end" : "http://localhost:7474/db/data/node/2" }, { "start" : "http://localhost:7474/db/data/node/7", "nodes" : [ "http://localhost:7474/db/data/node/7", "http://localhost:7474/db/data/node/6", "http://localhost:7474/db/data/node/2" ], "length" : 2, "relationships" : [ "http://localhost:7474/db/data/relationship/0", "http://localhost:7474/db/data/relationship/9" ], "end" : "http://localhost:7474/db/data/node/2" } ]
If no path algorithm is specified, a ShortestPath
algorithm with a max
depth of 1 will be chosen. In this example, the max_depth
is set to 3
in order to find the shortest path between 3 linked nodes.
Example request
POST
http://localhost:7474/db/data/node/14/path
Accept:
application/json
Content-Type:
application/json
{ "to":"http://localhost:7474/db/data/node/9", "max_depth":3, "relationships":{ "type":"to", "direction":"out" }, "algorithm":"shortestPath" }
Example response
200:
OK
Content-Type:
application/json
{ "start" : "http://localhost:7474/db/data/node/14", "nodes" : [ "http://localhost:7474/db/data/node/14", "http://localhost:7474/db/data/node/10", "http://localhost:7474/db/data/node/9" ], "length" : 2, "relationships" : [ "http://localhost:7474/db/data/relationship/11", "http://localhost:7474/db/data/relationship/17" ], "end" : "http://localhost:7474/db/data/node/9" }
Example request
POST
http://localhost:7474/db/data/node/29/path
Accept:
application/json
Content-Type:
application/json
{ "to":"http://localhost:7474/db/data/node/32", "cost_property":"cost", "relationships":{ "type":"to", "direction":"out" }, "algorithm":"dijkstra" }
Example response
200:
OK
Content-Type:
application/json
{ "weight" : 2.0, "start" : "http://localhost:7474/db/data/node/29", "nodes" : [ "http://localhost:7474/db/data/node/29", "http://localhost:7474/db/data/node/30", "http://localhost:7474/db/data/node/32" ], "length" : 2, "relationships" : [ "http://localhost:7474/db/data/relationship/33", "http://localhost:7474/db/data/relationship/34" ], "end" : "http://localhost:7474/db/data/node/32" }
Example request
POST
http://localhost:7474/db/data/node/20/path
Accept:
application/json
Content-Type:
application/json
{ "to":"http://localhost:7474/db/data/node/23", "cost_property":"cost", "relationships":{ "type":"to", "direction":"out" }, "algorithm":"dijkstra" }
Example response
200:
OK
Content-Type:
application/json
{ "weight" : 6.0, "start" : "http://localhost:7474/db/data/node/20", "nodes" : [ "http://localhost:7474/db/data/node/20", "http://localhost:7474/db/data/node/21", "http://localhost:7474/db/data/node/18", "http://localhost:7474/db/data/node/19", "http://localhost:7474/db/data/node/16", "http://localhost:7474/db/data/node/17", "http://localhost:7474/db/data/node/23" ], "length" : 6, "relationships" : [ "http://localhost:7474/db/data/relationship/20", "http://localhost:7474/db/data/relationship/22", "http://localhost:7474/db/data/relationship/24", "http://localhost:7474/db/data/relationship/27", "http://localhost:7474/db/data/relationship/29", "http://localhost:7474/db/data/relationship/30" ], "end" : "http://localhost:7474/db/data/node/23" }
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