added grpc server and client code for golang

.gitignore

@@ -1,2 +1,3 @@
 node_modules
 *.pyc
+.idea

client/golang/client.go

@@ -0,0 +1,31 @@
+package main
+
+import (
+	pb "github.com/johnkariuki/grpc-protobuf-tutorial/proto"
+	"google.golang.org/grpc"
+	"log"
+	"context"
+	"fmt"
+)
+
+var employees = map[string]*pb.Employee{
+	"eligible": &pb.Employee{12,"Peter",19,10},
+	"ineligible": &pb.Employee{14,"John",13,29},
+}
+
+func main(){
+	conn,err := grpc.Dial("localhost:50050",grpc.WithInsecure())
+	if err != nil {
+		log.Fatalf("did not connect :%v",err)
+	}
+	defer conn.Close()
+	c := pb.NewEmployeeLeaveDaysServiceClient(conn)
+	for _,emp := range employees {
+		eligibility, err := c.EligibleForLeave(context.Background(), emp)
+		if err != nil {
+			log.Fatalf("got error %v", err)
+		}
+		fmt.Printf("Eligibility of %v : %v\n",emp.Name,eligibility.Eligible)
+	}
+
+}

server/golang/server.go

@@ -0,0 +1,38 @@
+package main
+
+import (
+	"context"
+	pb "github.com/johnkariuki/grpc-protobuf-tutorial/proto"
+	"log"
+	"net"
+
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/reflection"
+)
+
+const (
+	port = ":50050"
+)
+
+type employeeLeaveDays struct{}
+
+func (e *employeeLeaveDays) EligibleForLeave(ctx context.Context, emp *pb.Employee) (*pb.LeaveEligibility, error) {
+	return &pb.LeaveEligibility{emp.AccruedLeaveDays >= emp.RequestedLeaveDays}, nil
+}
+
+func (e *employeeLeaveDays) GrantLeave(ctx context.Context, emp *pb.Employee) (*pb.LeaveFeedback, error) {
+	return &pb.LeaveFeedback{true, emp.AccruedLeaveDays - emp.RequestedLeaveDays, emp.RequestedLeaveDays}, nil
+}
+
+func main() {
+	lis, err := net.Listen("tcp", port)
+	if err != nil {
+		log.Fatalf("failed to listen %v", err)
+	}
+	s := grpc.NewServer()
+	pb.RegisterEmployeeLeaveDaysServiceServer(s, &employeeLeaveDays{})
+	reflection.Register(s)
+	if err = s.Serve(lis); err != nil {
+		log.Fatalf("failed to serve %v", err)
+	}
+}