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/243/paths
Accept:
application/json
Content-Type:
application/json
{ "to" : "http://localhost:7474/db/data/node/238", "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/243", "nodes" : [ "http://localhost:7474/db/data/node/243", "http://localhost:7474/db/data/node/239", "http://localhost:7474/db/data/node/238" ], "length" : 2, "relationships" : [ "http://localhost:7474/db/data/relationship/125", "http://localhost:7474/db/data/relationship/131" ], "end" : "http://localhost:7474/db/data/node/238" }, { "start" : "http://localhost:7474/db/data/node/243", "nodes" : [ "http://localhost:7474/db/data/node/243", "http://localhost:7474/db/data/node/242", "http://localhost:7474/db/data/node/238" ], "length" : 2, "relationships" : [ "http://localhost:7474/db/data/relationship/124", "http://localhost:7474/db/data/relationship/133" ], "end" : "http://localhost:7474/db/data/node/238" } ]
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/250/path
Accept:
application/json
Content-Type:
application/json
{ "to" : "http://localhost:7474/db/data/node/245", "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/250", "nodes" : [ "http://localhost:7474/db/data/node/250", "http://localhost:7474/db/data/node/246", "http://localhost:7474/db/data/node/245" ], "length" : 2, "relationships" : [ "http://localhost:7474/db/data/relationship/135", "http://localhost:7474/db/data/relationship/141" ], "end" : "http://localhost:7474/db/data/node/245" }
Example request
POST
http://localhost:7474/db/data/node/265/path
Accept:
application/json
Content-Type:
application/json
{ "to" : "http://localhost:7474/db/data/node/268", "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/265", "nodes" : [ "http://localhost:7474/db/data/node/265", "http://localhost:7474/db/data/node/266", "http://localhost:7474/db/data/node/268" ], "length" : 2, "relationships" : [ "http://localhost:7474/db/data/relationship/157", "http://localhost:7474/db/data/relationship/158" ], "end" : "http://localhost:7474/db/data/node/268" }
Example request
POST
http://localhost:7474/db/data/node/256/path
Accept:
application/json
Content-Type:
application/json
{ "to" : "http://localhost:7474/db/data/node/259", "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/256", "nodes" : [ "http://localhost:7474/db/data/node/256", "http://localhost:7474/db/data/node/257", "http://localhost:7474/db/data/node/254", "http://localhost:7474/db/data/node/255", "http://localhost:7474/db/data/node/252", "http://localhost:7474/db/data/node/253", "http://localhost:7474/db/data/node/259" ], "length" : 6, "relationships" : [ "http://localhost:7474/db/data/relationship/144", "http://localhost:7474/db/data/relationship/146", "http://localhost:7474/db/data/relationship/148", "http://localhost:7474/db/data/relationship/151", "http://localhost:7474/db/data/relationship/153", "http://localhost:7474/db/data/relationship/154" ], "end" : "http://localhost:7474/db/data/node/259" }
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