Agfdhyk

I'm trying to get the path of a node in my Database where i have to do some stuff in. I'm trying to get this path with a query.

Here my database structure:

{

"root" {

    "Sensori": LONG PATH HERE->

                             "M25S03": {

                                "latitude": 45.4986468234261,

                                "longitude": 9.16259765625,

                                "no2": 0.89,

                                "pm1": 4.54,

                                "pm10": 1.51,

                                "pm2_5": 1.84,

                                "pressione": 6.1,

                                "temperatura": 2.06,

                                "umidità": 8.92,

                                "voc": 9.4}

},

"Zones": {

    "Areas": {

        "CAP-20100": {

            "ZONA-01": {},

            "ZONA-02": {},

            "ZONA-07": {

                "geometry": {

                    "coordinates": [[[9.040955, 45.446847], ...A LOT OF POINTS, ...]],

                    "type": "Polygon"

                },

                "properties": {

                },

                "type": "Feature"

            }}}}

}

When a new record like "M25S03" is inserted in the DB a triggered function start.
This function get the latitude and longitude to instantiate a point and then it has to understand in wich "polygon", stored in the table "Zones", the point is in.

Here the triggered Function:

export const onSensorCreate = functions.database

.ref('/Sensori/{sensorId}/feeds/{monthId}/{dayId}/{hourId}/{feedId}/')

.onCreate((snapshot, context) => {







    const feedId: string = context.params.monthId + context.params.dayId + context.params.hourId + context.params.feedId

    const sensorId = context.params.sensorId

    console.log('new feed (id Feed:' + feedId + ') from' + sensorId)





    const feed = snapshot.val()7)





    var ref = snapshot.ref,

        root = ref.root,

        zoneRef = root.child('Zones'),

        areas = zoneRef.child('Areas'),





    var latitude = feed.latitude

    var longitude = feed.longitude

    var lnglat: number = [longitude, latitude]



    var pathArea: database.Reference = getPathAreas(areas, lnglat)

    .

    .

    .

and then the function getPatAreas wich has to return the Path of the database wich refer to the polygon containing the point

function getPathAreas(areas: database.Reference, lnglat: number): database.Reference {



var path: database.Reference

var point = turf.point(lnglat)



var query = areas.once('value', function (areasSnapshot) {



    areasSnapshot.forEach(

        function (childCapSnapshot) {



            var a = childCapSnapshot.forEach(

                function (childZoneSnapshot) {



                    const vettoreCoordinatePoligono: number = childZoneSnapshot.val().geometry.coordinates

                    var polygon = turf.polygon(vettoreCoordinatePoligono)



                    if (turf.booleanPointInPolygon(point, polygon)) {



                        path = childZoneSnapshot.ref

                        console.log("PATH AREA nell'if: " + path)



                        return true

                    }



                    return false

                })

            console.log("XXX " + path)

            return a

        }





    )

    console.log("YYY" + path)

})



console.log("ZZZ " + path)







if (path != undefined)

    return path

else

    return areas.root.child("UnrecorderAreas")

}

The query is asynchronous becouse is in a callback function, but i need to use path before that query is solved.
Infact by adding some control log in the code i can see that :

4:08:36.285 PM onSensorCreate Function execution took 15664 ms, finished with status: 'ok'

               HERE I GOT THE RIGHT VALUE

4:08:36.194 PM onSensorCreate YYYhttps://sensesquaredb.firebaseio.com/Zones/Areas/CAP-20100/ZONA-07

               I GOT THE RIGHT VALUE HERE TOO

4:08:36.194 PM onSensorCreate XXX https://sensesquaredb.firebaseio.com/Zones/Areas/CAP-20100/ZONA-07

4:08:36.194 PM onSensorCreate PATH AREA nell'if: https://sensesquaredb.firebaseio.com/Zones/Areas/CAP-20100/ZONA-07

4:08:32.182 PM onSensorCreate pathArea https://sensesquaredb.firebaseio.com/UnrecorderAreas

              HERE I GOT UNDEFINED 

4:08:32.181 PM onSensorCreate ZZZ undefined

4:08:20.888 PM onSensorCreate new feed (id Feed:2018M11D13H16M08S20) fromSensore4455

4:08:20.622 PM onSensorCreate Billing account not configured. External network is not accessible and quotas are severely limited. Configure billing account to remove these restrictions

4:08:20.622 PM onSensorCreate Function execution started

So, how do i get this value in a non-asynchronous way?