Feature/Build spatial index based on google::s2

integration/cmd/chargestations-connectivity-gen/doc.go

@@ -0,0 +1,17 @@
+// package main contains the tool of chargestation-connectivity generator
+// stage 1:
+// inputs is json file
+// => convert to slice of [id:string,location: lat,lon]
+// => calculate cellids for each point(for all levels)
+// => build revese index for cellid -> ids
+// stage 2:
+// => iterate each point
+// => generate a circle(s2::cap), find all cellids intersect with that circle
+// => retrieve all ids
+// => generate result of id(from), ids(all ids in certain distance)
+// stage 3:
+// => load data from file
+// => for each line, its formid and all other ids
+// => calculate distance between fromid and all other ids
+// => sort result based on distance and write back to file
+package main

integration/cmd/chargestations-connectivity-gen/main.go

@@ -0,0 +1,10 @@
+package main
+
+import (
+	"fmt"
+)
+
+func main() {
+	// @todo: add logic to generate connectivity for charge stations
+	fmt.Print("Hello World!")
+}

integration/go.mod

@@ -3,6 +3,7 @@ module github.com/Telenav/osrm-backend/integration
 go 1.13
 
 require (
+	github.com/golang/geo v0.0.0-20200319012246-673a6f80352d
 	github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b
 	github.com/golang/protobuf v1.3.2
 	github.com/golang/snappy v0.0.1

integration/go.sum

@@ -1,6 +1,8 @@
 cloud.google.com/go v0.26.0/go.mod h1:aQUYkXzVsufM+DwF1aE+0xfcU+56JwCaLick0ClmMTw=
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
 github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDkc90ppPyw=
+github.com/golang/geo v0.0.0-20200319012246-673a6f80352d h1:C/hKUcHT483btRbeGkrRjJz+Zbcj8audldIi9tRJDCc=
+github.com/golang/geo v0.0.0-20200319012246-673a6f80352d/go.mod h1:QZ0nwyI2jOfgRAoBvP+ab5aRr7c9x7lhGEJrKvBwjWI=
 github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b h1:VKtxabqXZkF25pY9ekfRL6a582T4P37/31XEstQ5p58=
 github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b/go.mod h1:SBH7ygxi8pfUlaOkMMuAQtPIUF8ecWP5IEl/CR7VP2Q=
 github.com/golang/mock v1.1.1/go.mod h1:oTYuIxOrZwtPieC+H1uAHpcLFnEyAGVDL/k47Jfbm0A=

integration/service/spatialindexer/doc.go

@@ -0,0 +1,20 @@
+// package spatialindexer answers query of nearest points(place, point of interest) for conditions
+// such as center location, radius, etc
+//
+// Sample Scenario 1: Build connectivity for charge stations during pro-processing
+// indexer := NewS2Indexer().Build(poiCsvFile)
+// for _, stationPoint := range chargeStations {
+// 	nearbyStations := indexer.FindNearByIDs(stationPoint, 800km, -1)
+// 	rankedStations := indexer.RankingIDsByShortestDistance(stationPoint, nearbyStations)
+// }
+//
+//
+// Sample Scenario 2: Dump S2Indexer's content to folder
+// indexer.Dump(folderPath)
+//
+//
+// Sample Scenario 3: Query reachable charge stations with current energy level
+// indexer := NewS2Indexer().Load(folderPath)
+// nearbyStations := indexer.FindNearByIDs(currentPoint, currentEnergyLevel, -1)
+//
+package spatialindexer

integration/service/spatialindexer/interface.go

@@ -0,0 +1,41 @@
+package spatialindexer
+
+// Location for poi point
+// @todo: will be replaced by the one in map
+type Location struct {
+	Latitude  float64
+	Longitude float64
+}
+
+// PointInfo records point related information such as ID and location
+type PointInfo struct {
+	ID       PointID
+	Location Location
+}
+
+// RankedPointInfo used to record ranking result, distance to specific point could be used for ranking
+type RankedPointInfo struct {
+	PointInfo
+	Distance float64
+}
+
+// PointID defines ID for given point(location, point of interest)
+// Only the data used for pre-processing contains valid PointID
+type PointID int64
+
+// Finder answers special query
+type Finder interface {
+
+	// FindNearByPointIDs returns a group of points near to given center location
+	FindNearByPointIDs(center Location, radius float64, limitCount int) []PointInfo
+}
+
+// Ranker used to ranking a group of points
+type Ranker interface {
+
+	// RankPointIDsByGreatCircleDistance ranks a group of points based on great circle distance to given location
+	RankPointIDsByGreatCircleDistance(center Location, nearByIDs []PointInfo) []RankedPointInfo
+
+	// RankPointIDsByShortestDistance ranks a group of points based on shortest path distance to given location
+	RankPointIDsByShortestDistance(center Location, nearByIDs []PointInfo) []RankedPointInfo
+}

integration/service/spatialindexer/poiloader/loader.go

@@ -0,0 +1,26 @@
+package poiloader
+
+import (
+	"encoding/json"
+	"io/ioutil"
+
+	"github.com/golang/glog"
+)
+
+// LoadData accepts json file with points data and returns deserialized result
+func LoadData(filePath string) ([]Element, error) {
+	var elements []Element
+
+	file, err := ioutil.ReadFile(filePath)
+	if err != nil {
+		glog.Errorf("While load file %s, met error %v\n", filePath, err)
+		return elements, err
+	}
+
+	err = json.Unmarshal(file, &elements)
+	if err != nil {
+		glog.Errorf("While unmarshal json file %s, met error %v\n", filePath, err)
+		return elements, err
+	}
+	return elements, nil
+}

integration/service/spatialindexer/poiloader/poi_format.go

@@ -0,0 +1,70 @@
+package poiloader
+
+// Element represent information loaded for point record
+type Element struct {
+	ID                int64             `json:"id"`
+	VendorCode        VendorCode        `json:"vendor_code"`
+	VendorPoiID       string            `json:"vendor_poi_id"`
+	Lat               float64           `json:"lat"`
+	Lon               float64           `json:"lon"`
+	NavLat            float64           `json:"nav_lat"`
+	NavLon            float64           `json:"nav_lon"`
+	DisLat            float64           `json:"dis_lat"`
+	DisLon            float64           `json:"dis_lon"`
+	MapLinkID         int64             `json:"map_link_id"`
+	SideOfStreet      string            `json:"side_of_street"`
+	Country           Country           `json:"country"`
+	SpaceID           SpaceID           `json:"space_id"`
+	AirportCode       string            `json:"airport_code"`
+	IsNational        bool              `json:"is_national"`
+	IsStateImportance bool              `json:"is_state_importance"`
+	IsCityImportance  bool              `json:"is_city_importance"`
+	Fax               string            `json:"fax"`
+	Phone             *CategoryIDGather `json:"phone"`
+	EncodedPhone      string            `json:"encoded_phone"`
+	Email             string            `json:"email"`
+	WebURL            string            `json:"web_url"`
+	CategoryIDGather  *CategoryIDGather `json:"category_id_gather"`
+	ChainGather       string            `json:"chain_gather"`
+	RawCategoryGather string            `json:"raw_category_gather"`
+	ChildGather       string            `json:"child_gather"`
+	ParentGather      string            `json:"parent_gather"`
+	Hilbert           float64           `json:"hilbert"`
+	Amenity           Amenity           `json:"amenity"`
+}
+
+// Amenity is defined by OSM format: https://wiki.openstreetmap.org/wiki/Tag:amenity%3Dcharging_station
+type Amenity string
+
+const (
+	ChargingStation Amenity = "charging_station"
+)
+
+// Country records IOS code
+type Country string
+
+const (
+	Usa Country = "USA"
+)
+
+// SpaceID is used to define a code for political defined administrative area
+type SpaceID string
+
+const (
+	UsaCA SpaceID = "USA_CA"
+)
+
+// VendorCode defines data source provider
+type VendorCode string
+
+const (
+	Noel VendorCode = "NOEL"
+	Noft VendorCode = "NOFT"
+	Nolp VendorCode = "NOLP"
+)
+
+// CategoryIDGather records aggregate data for certain type of point
+type CategoryIDGather struct {
+	Integer *int64
+	String  *string
+}

integration/service/spatialindexer/poiloader/sample_input.json

@@ -0,0 +1,64 @@
+[
+   {
+      "id":12345,
+      "vendor_code":"NOFT",
+      "vendor_poi_id":"NOFT-10_NREL99930@-@NOCO-37145190@-@NOCO-996595530",
+      "lat":0.48651,
+      "lon":0.66526,
+      "nav_lat":0.48651,
+      "nav_lon":0.66526,
+      "dis_lat":0.48651,
+      "dis_lon":0.66526,
+      "map_link_id":12345,
+      "side_of_street":"+",
+      "country":"USA",
+      "space_id":"USA_CA",
+      "airport_code":"NULL",
+      "is_national":false,
+      "is_state_importance":false,
+      "is_city_importance":false,
+      "fax":"NULL",
+      "phone":123456789,
+      "encoded_phone":"123456789",
+      "email":"NULL",
+      "web_url":"NULL",
+      "category_id_gather":"771``794``915",
+      "chain_gather":"1364@-@@-@",
+      "raw_category_gather":"NT@-@3578``NT@-@6000``NAICS@-@522110``NT@-@5540",
+      "child_gather":"NULL",
+      "parent_gather":"1718449@-@1``2216423@-@1",
+      "hilbert":2.32E+11,
+      "amenity":"charging_station"
+   },
+   {
+    "id":12346,
+    "vendor_code":"NOFT",
+    "vendor_poi_id":"NOFT-10_NREL99930@-@NOCO-37145190@-@NOCO-996595530",
+    "lat":0.48651,
+    "lon":0.66526,
+    "nav_lat":0.48651,
+    "nav_lon":0.66526,
+    "dis_lat":0.48651,
+    "dis_lon":0.66526,
+    "map_link_id":12345,
+    "side_of_street":"+",
+    "country":"USA",
+    "space_id":"USA_CA",
+    "airport_code":"NULL",
+    "is_national":false,
+    "is_state_importance":false,
+    "is_city_importance":false,
+    "fax":"NULL",
+    "phone":123456789,
+    "encoded_phone":"123456789",
+    "email":"NULL",
+    "web_url":"NULL",
+    "category_id_gather":"771``794``915",
+    "chain_gather":"1364@-@@-@",
+    "raw_category_gather":"NT@-@3578``NT@-@6000``NAICS@-@522110``NT@-@5540",
+    "child_gather":"NULL",
+    "parent_gather":"1718449@-@1``2216423@-@1",
+    "hilbert":2.32E+11,
+    "amenity":"charging_station"
+ }
+]

integration/service/spatialindexer/s2indexer/builder.go

@@ -0,0 +1,51 @@
+package s2indexer
+
+import (
+	"github.com/Telenav/osrm-backend/integration/service/spatialindexer"
+	"github.com/golang/geo/s2"
+)
+
+// https://s2geometry.io/resources/s2cell_statistics.html
+// Level = 6 means average area size is 20754.64km2
+// Level = 9 means average area size is 324.29km2
+const minS2Level = 9
+
+// Level = 19 means average area size is 309.27km2
+// Level = 20 means average area size is 77.32km2
+const maxS2Level = 20
+
+func build(points []spatialindexer.PointInfo, minLevel, maxLevel int) map[s2.CellID][]spatialindexer.PointID {
+	pointID2CellIDs := make(map[spatialindexer.PointID][]s2.CellID)
+	cellID2PointIDs := make(map[s2.CellID][]spatialindexer.PointID)
+
+	for _, p := range points {
+		leafCellID := s2.CellFromLatLng(s2.LatLngFromDegrees(p.Location.Latitude, p.Location.Longitude)).ID()
+
+		var cellIDs []s2.CellID
+		// For level = 30, its parent equal to current
+		// So no need append leafCellID into cellIDs outside of for loop
+		for i := leafCellID.Level(); i > minLevel; i-- {
+			if i > maxLevel {
+				continue
+			}
+
+			parentCellID := leafCellID.Parent(i)
+			cellIDs = append(cellIDs, parentCellID)
+		}
+
+		pointID2CellIDs[p.ID] = cellIDs
+	}
+
+	for pointID, cellIDs := range pointID2CellIDs {
+		for _, cellID := range cellIDs {
+			if _, ok := cellID2PointIDs[cellID]; !ok {
+				var pointIDs []spatialindexer.PointID
+				cellID2PointIDs[cellID] = pointIDs
+			}
+
+			cellID2PointIDs[cellID] = append(cellID2PointIDs[cellID], pointID)
+		}
+	}
+
+	return cellID2PointIDs
+}