initial commit

.gitignore

@@ -0,0 +1 @@
+.idea

car/main.go

@@ -0,0 +1,205 @@
+package main
+
+import (
+	"log"
+	"google.golang.org/grpc"
+	pb "github.com/vds/gen"
+	"context"
+	"os"
+	"time"
+	"flag"
+	"io/ioutil"
+	"encoding/json"
+	"fmt"
+	"errors"
+	"math/rand"
+)
+
+var trainId string
+var line string
+var direction bool
+var inService bool
+
+type Stop struct {
+	Name     string
+	NextStop int
+}
+type Line struct {
+	LineName string
+	Stops    []Stop
+}
+
+type Data struct {
+	Routes []Line
+}
+
+type Train struct {
+	status             string
+	trainId            string
+	line               Line
+	direction          bool
+	stopNum            int
+	holdCount          int
+	speed              float64
+	seconds            float64
+	distanceToNextStop int
+	minutesToNextStop  int32
+}
+
+func (t *Train) printRoute() string {
+	return fmt.Sprintf("Line %s. Heading %s. %s => %s station",
+		t.line.LineName,
+		determineDirection(t.direction),
+		t.status,
+		t.line.Stops[t.stopNum].Name)
+}
+func (t *Train) ping() *pb.TrainPing {
+
+	return &pb.TrainPing{
+		TrainId:           t.trainId,
+		Route:             t.printRoute(),
+		Status:            t.status,
+		Speed:             t.speed,
+		NextStop:          float64(t.distanceToNextStop),
+		MinutesToNextStop: t.minutesToNextStop,
+		Line:              t.line.LineName,
+		Direction:         determineDirection(t.direction),
+		NextStation:       t.line.Stops[t.stopNum].Name,
+		Timestamp:         0,
+	}
+}
+
+func (t *Train) accelerate() {
+	max := 12.0
+	a := 2.0
+	distanceTraveled := (t.speed * t.seconds) + (0.5 * a * (t.seconds + 1*t.seconds + 1))
+	t.distanceToNextStop -= int(distanceTraveled)
+	t.speed += distanceTraveled / float64(1.0)
+	if t.speed > max {
+		t.speed = max
+	}
+	t.minutesToNextStop = int32(t.distanceToNextStop / int(t.speed))
+	t.seconds += 1
+
+}
+
+func (t *Train) moveTrain() {
+	if t.status == "NOT_IN_SERVICE" {
+		t.status = "IN_TRANSIT"
+		t.distanceToNextStop = t.line.Stops[t.stopNum].NextStop
+	} else if t.status == "IN_TRANSIT" {
+		t.accelerate()
+		if t.distanceToNextStop <= 0 {
+			t.status = "HOLDING"
+			t.distanceToNextStop = 0
+			t.speed = 0
+			t.seconds = 0
+			t.minutesToNextStop = 0
+			t.holdCount = rand.Intn(3)
+		}
+	} else if t.status == "HOLDING" {
+		if t.holdCount != 0 {
+			t.holdCount -= 1
+		} else {
+			t.status = "DISEMBARK"
+		}
+
+	} else if t.status == "DISEMBARK" {
+		t.status = "IN_TRANSIT"
+		if t.stopNum < len(t.line.Stops)-1 && t.direction {
+			t.stopNum += 1
+		} else if t.stopNum > 0 && !t.direction {
+			t.stopNum -= 1
+		} else {
+			if t.direction {
+				t.stopNum = len(t.line.Stops) - 1
+			} else {
+				t.stopNum = 0
+			}
+			t.direction = !t.direction
+			time.Sleep(10 * time.Second)
+		}
+		t.distanceToNextStop = t.line.Stops[t.stopNum].NextStop
+	}
+	time.Sleep(5 * time.Second)
+}
+
+func determineDirection(direction bool) string {
+	if direction {
+		return "INBOUND"
+	} else {
+		return "OUTBOUND"
+	}
+}
+
+func findLine(routes []Line, lineName string) (Line, error) {
+	for i, r := range routes {
+		if r.LineName == lineName {
+			return routes[i], nil
+		}
+	}
+	return Line{}, errors.New("line not found")
+}
+
+func runTrain(client pb.MasterServiceClient) error {
+	var data Data
+	dat, err := ioutil.ReadFile("./car/routes.json")
+	if err != nil {
+		log.Fatalf("Error reading file %+v", err)
+		return err
+	}
+	err = json.Unmarshal(dat, &data)
+	if err != nil {
+		log.Fatalf("Error parsing json %+v", err)
+	}
+	selectedLine, err := findLine(data.Routes, line)
+	if err != nil {
+		log.Fatalf("Unable to find route information")
+		return err
+	}
+
+	train := &Train{
+		trainId:   trainId,
+		line:      selectedLine,
+		status:    "NOT_IN_SERVICE",
+		direction: direction,
+	}
+
+	stream, err := client.ReceiveTrainPing(context.Background())
+	if err != nil {
+		log.Printf("failed with %+v", err)
+		return err
+	}
+	for {
+		train.moveTrain()
+		ping := train.ping()
+		log.Println("Ping sent: ", ping.TrainId, ping.Route, ping.Speed, ping.NextStop, ping.MinutesToNextStop)
+		err := stream.Send(ping)
+		if err != nil {
+			log.Fatalf("failed with %+v", err)
+			stream.CloseSend()
+			break
+		}
+	}
+	return err
+}
+
+func main() {
+	flag.StringVar(&trainId, "trainId", "1593", "The Id for the train")
+	flag.StringVar(&line, "line", "K", "The line the train is on")
+	flag.BoolVar(&direction, "direction", true, "Direction true for inbound false for outbound")
+	flag.BoolVar(&inService, "inService", false, "Train is in or out of service")
+	var opts []grpc.DialOption
+
+	opts = append(opts, grpc.WithInsecure())
+	conn, err := grpc.Dial("localhost:8881", opts...)
+	if err != nil {
+		log.Fatalf("fail to dial: %v", err)
+	}
+	defer conn.Close()
+	client := pb.NewMasterServiceClient(conn)
+	err = runTrain(client)
+	if err != nil {
+		os.Exit(1)
+	}
+}

car/routes.json

@@ -0,0 +1,19 @@
+{
+  "routes": [
+    {
+      "lineName": "K",
+      "stops": [
+        {"name": "Overlook", "nextStop":300},
+        {"name":"Fordham", "nextStop":200},
+        {"name":"Devonshire","nextStop":500},
+        {"name":"Oklahoma","nextStop":300},
+        {"name":"Litteton","nextStop":100},
+        {"name":"Oak Valley","nextStop":600},
+        {"name":"Woodsman","nextStop":200},
+        {"name":"Brookings", "nextStop":300},
+        {"name":"Glenwood", "nextStop":1000},
+        {"name":"South Poplar", "nextStop":200}
+      ]
+    }
+  ]
+}