initial commit

valhalla.go

@@ -0,0 +1,102 @@
+package routing
+
+import (
+	"bytes"
+	"errors"
+	"io/ioutil"
+	"net/http"
+
+	"git.coopgo.io/coopgo-platform/routing-service/encoding/polylines"
+	"git.coopgo.io/coopgo-platform/routing-service/proto/valhalla"
+	"github.com/paulmach/orb"
+	"google.golang.org/protobuf/proto"
+)
+
+type ValhallaRouting struct {
+	BaseURL string
+}
+
+func NewValhallaRouting(baseURL string) (*ValhallaRouting, error) {
+	return &ValhallaRouting{
+		BaseURL: baseURL,
+	}, nil
+}
+
+func (v *ValhallaRouting) Route(locations []orb.Point) (route *Route, err error) {
+
+	valhalla_locations := []*valhalla.Location{}
+
+	for _, loc := range locations {
+		valhalla_locations = append(valhalla_locations, &valhalla.Location{
+			Ll: &valhalla.LatLng{
+				HasLat: &valhalla.LatLng_Lat{Lat: loc.Lat()},
+				HasLng: &valhalla.LatLng_Lng{Lng: loc.Lon()},
+			},
+		})
+	}
+
+	request := &valhalla.Api{
+		Options: &valhalla.Options{
+			Action:      valhalla.Options_route,
+			Locations:   valhalla_locations,
+			CostingType: valhalla.Costing_auto_,
+			Format:      valhalla.Options_pbf,
+		},
+	}
+
+	resp, err := v.protocolBufferRequest(request, "route")
+	if err != nil {
+		return nil, err
+	}
+
+	if len(resp.Directions.Routes) < 1 {
+		return nil, errors.New("no routes returnes by valhalla")
+	}
+
+	decodedLinestring := orb.LineString{}
+
+	for _, leg := range resp.Directions.Routes[0].Legs {
+		shape := leg.Shape
+		decodedShape := polylines.Decode(&shape, 6)
+		decodedLinestring = append(decodedLinestring, decodedShape...)
+	}
+
+	return &Route{
+		Summary: RouteSummary{
+			Polyline: polylines.Encode(decodedLinestring),
+		},
+	}, nil
+}
+
+func (v *ValhallaRouting) protocolBufferRequest(api *valhalla.Api, path string) (*valhalla.Api, error) {
+	data, err := proto.Marshal(api)
+	if err != nil {
+		return nil, err
+	}
+
+	req, err := http.NewRequest(http.MethodGet, v.BaseURL+path, bytes.NewBuffer(data))
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Set("Content-Type", "application/x-protobuf")
+
+	client := http.Client{}
+	resp, err := client.Do(req)
+	//resp, err := http.Post(v.BaseURL+path, "application/x-protobuf", bytes.NewBuffer(data))
+	if err != nil {
+		return nil, err
+	}
+
+	body, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return nil, err
+	}
+
+	response := valhalla.Api{}
+	err = proto.Unmarshal(body, &response)
+	if err != nil {
+		return nil, err
+	}
+
+	return &response, nil
+}