Cypher: find path using Scala AnormCypher? - scala

Question

AnormCypher doc provides an example how to retriev data using the Stream API:
http://anormcypher.org/
"The first way to access the results of a return query is to use the Stream API.
When you call apply() on any Cypher statement, you will receive a lazy Stream of CypherRow instances, where each row can be seen as a dictionary:
// Create Cypher query
val allCountries = Cypher("start n=node(*) where n.type = 'Country' return n.code as code, n.name as name")
// Transform the resulting Stream[CypherRow] to a List[(String,String)]
val countries = allCountries.apply().map(row =>
row[String]("code") -> row[String]("name")
).toList
I am trying to use the same aproach to get path with the following Cypher query:
MATCH p = (n {id: 'n5'})-[*]-(m) RETURN p;
Yet, when running this code:
Cypher("MATCH p = (n {id: 'n5'})-[*]-(m) RETURN p;")().map {row =>
println(row[Option[org.anormcypher.NeoRelationship]]("p"))
}
I get exception (see below). How to get path info from CypherRow in this case?
Exception in thread "main" java.lang.RuntimeException: TypeDoesNotMatch(Unexpected type while building a relationship)
at org.anormcypher.MayErr$$anonfun$get$1.apply(Utils.scala:21)
at org.anormcypher.MayErr$$anonfun$get$1.apply(Utils.scala:21)
at scala.util.Either.fold(Either.scala:97)
at org.anormcypher.MayErr.get(Utils.scala:21)
at org.anormcypher.CypherRow$class.apply(AnormCypher.scala:303)
at org.anormcypher.CypherResultRow.apply(AnormCypher.scala:309)
at bigdata.test.n4j.Simple$$anonfun$main$1.apply(Simple.scala:31)
at bigdata.test.n4j.Simple$$anonfun$main$1.apply(Simple.scala:29)
at scala.collection.immutable.Stream.map(Stream.scala:376)
at bigdata.test.n4j.Simple$.main(Simple.scala:29)

Answer 1

Paths in Cypher were changed as of 2.0, so you can't work with them easily directly, as they're not collections. There probably should be a new Path type of some sort in AnormCypher, but for now you can use paths along with relationships() or nodes().
For example, you could do this to extract the relationships:
Cypher("MATCH p = (n {id: 'n5'})-[*]-(m) RETURN relationships(p);")().map {row =>
println(row[Seq[NeoRelationship]]("relationships(p)"))
}