Improper variable handling in cypher directive

[johnymontana]

GraphQL schema:

type PointOfInterest {
  node_osm_id: Int!
  name: String
  lat: Float
  lon: Float
  location: Point
  poi_id: String
  shortestPathRouteToPOI(end_poi_id: String): [LatLng] @cypher(statement: """
    MATCH (b:PointOfInterest) WHERE b.poi_id = $end_poi_id
    MATCH p=shortestPath((this)-[:ROUTE*..200]-(b))
    UNWIND nodes(p) AS n
    RETURN {lon: n.location.longitude, lat: n.location.latitude} AS route
  """)
  dijkstraRouteToPOI(poi_id: String): [LatLng] @cypher(statement: """
    MATCH (b:PointOfInterest) WHERE b.poi_id = $poi_id
    CALL apoc.algo.dijkstra(this, b, 'ROUTE', 'distance') YIELD path, weight
    UNWIND nodes(path) AS n
    RETURN {lon: n.location.longitude, lat: n.location.latitude} AS route
  """)
  aStarRouteToPOI(poi_id: String): [LatLng] @cypher(statement: """
    MATCH (b:PointOfInterest) WHERE b.poi_id = $poi_id
    CALL apoc.algo.aStar(this, b, 'ROUTE', 'distance', 'lat', 'lon') YIELD path, weight
    UNWIND nodes(path) AS n
    RETURN {lon: n.location.longitude, lat: n.location.latitude} AS route
  """)
}

type LatLng {
  lat: Float
  lon: Float
}

type Query {
  POIsInRadius(lat: Float, lon: Float, radius: Float): [PointOfInterest] @cypher(statement: """
  MATCH (p:PointOfInterest) 
  WHERE distance(p.location, point({latitude: $lat, longitude:$lon})) < ( $radius * 1000)
  RETURN p
  """)
}

GraphQL query:

query routeQuery($startPOI: String, $endPOI: String) {
  PointOfInterest(poi_id: $startPOI) {
    name
    route: shortestPathRouteToPOI(end_poi_id: $endPOI) {
      lat
      lon
    }
  }
}

GraphQL variables:

{
"startPOI": "Old Ship Saloon37.7977871-122.4007139",
"endPOI": "Gestalt37.7647122-122.4233225"
}

generated cypher query:

MATCH (pointOfInterest:PointOfInterest {poi_id:$poi_id}) RETURN pointOfInterest { .name ,shortestPathRouteToPOI: [ pointOfInterest_shortestPathRouteToPOI IN apoc.cypher.runFirstColumn("MATCH (b:PointOfInterest) WHERE b.poi_id = $end_poi_id
MATCH p=shortestPath((this)-[:ROUTE*..200]-(b))
UNWIND nodes(p) AS n
RETURN {lon: n.location.longitude, lat: n.location.latitude} AS route", {this: pointOfInterest}, true) | pointOfInterest_shortestPathRouteToPOI { .lat , .lon }] } AS pointOfInterest SKIP $offset

genereated cypher parameters:

{ offset: 0,
  first: -1,
  poi_id: 'Old Ship Saloon37.7977871-122.4007139',
  '1_end_poi_id': undefined }

Expected value of 1_end_poi_id to be Gestalt37.7647122-122.4233225 and not undefined.

[johnymontana]

Note that when GraphQL variables are not used the value is inlined in the generated cypher query:

 {
  PointOfInterest(poi_id: "Old Ship Saloon37.7977871-122.4007139") {
    name
    route: shortestPathRouteToPOI(poi_id: "Gestalt37.7647122-122.4233225") {
      lat
      lon
    }
  }
}

MATCH (pointOfInterest:PointOfInterest {poi_id:$poi_id}) RETURN pointOfInterest { .name ,shortestPathRouteToPOI: [ pointOfInterest_shortestPathRouteToPOI IN apoc.cypher.runFirstColumn("MATCH (b:PointOfInterest) WHERE b.poi_id = $poi_id
MATCH p=shortestPath((this)-[:ROUTE*..200]-(b))
UNWIND nodes(p) AS n
RETURN {lon: n.location.longitude, lat: n.location.latitude} AS route", {this: pointOfInterest, poi_id: "Gestalt37.7647122-122.4233225"}, true) | pointOfInterest_shortestPathRouteToPOI { .lat , .lon }] } AS pointOfInterest SKIP $offset

{ offset: 0,
  first: -1,
  poi_id: 'Old Ship Saloon37.7977871-122.4007139',
  '1_poi_id': 'Gestalt37.7647122-122.4233225' }

[johnymontana]

After #200 the generated Cypher query and parameters are:

MATCH (`pointOfInterest`:`PointOfInterest` {poi_id:$poi_id}) RETURN `pointOfInterest` { .name ,shortestPathRouteToPOI: [ pointOfInterest_shortestPathRouteToPOI IN apoc.cypher.runFirstColumn("MATCH (b:PointOfInterest) WHERE b.poi_id = $end_poi_id
MATCH p=shortestPath((this)-[:ROUTE*..200]-(b))
UNWIND nodes(p) AS n
RETURN {lon: n.location.longitude, lat: n.location.latitude} AS route", {this: pointOfInterest, end_poi_id: "Gestalt37.7647122-122.4233225"}, true) | pointOfInterest_shortestPathRouteToPOI { .lat , .lon }] } AS `pointOfInterest` SKIP $offset
{ offset: 0,
  first: -1,
  poi_id: 'Old Ship Saloon37.7977871-122.4007139',
  '1_end_poi_id': 'Gestalt37.7647122-122.4233225' }

which fixes the issue of not passing the end_poi_id parameter value to the subquery in apoc.cypher.runFirstColumn, however the value is inlined to the subquery for end_poi_id. To be consistent with parameterization we should make use of the Cypher param 1_end_poi_id instead:

{this: pointOfInterest, end_poi_id: $1_end_poi_id},

[danielmcmillan]

Seems like there is still an issue when a GraphQL variable is used for a field within an object passed as a parameter.

Schema:

input BInput {
  param: String
}
type A {
  b(bInput: BInput): String
    @cypher(statement: "RETURN $bInput.param;")
}

Query:

query(var: String) {
  A {
    b(bInput: {param: $var})
  }
}

Variables: {"var": "VALUE"}

In the generated Cypher parameters, 1_bInput is { param: undefined } instead of { param: 'VALUE' }.

[johnymontana]

Fixed in #213