Add grpc check example. (#306)

* Add grpc check example.

Signed-off-by: Bo-Yi Wu <appleboy.tw@gmail.com>

* add missing package.

Signed-off-by: Bo-Yi Wu <appleboy.tw@gmail.com>

rpc/client_grpc_health.go

@@ -2,7 +2,6 @@ package rpc
 
 import (
 	"context"
-	"time"
 
 	"github.com/appleboy/gorush/rpc/proto"
 
@@ -13,8 +12,6 @@ import (
 // generate protobuffs
 //   protoc --go_out=plugins=grpc,import_path=proto:. *.proto
 
-var backoff = time.Second
-
 type healthClient struct {
 	client proto.HealthClient
 	conn   *grpc.ClientConn
@@ -37,25 +34,24 @@ func (c *healthClient) Check(ctx context.Context) (bool, error) {
 	var err error
 	req := new(proto.HealthCheckRequest)
 
-	for {
-		res, err = c.client.Check(ctx, req)
-		if err == nil {
-			if res.GetStatus() == proto.HealthCheckResponse_SERVING {
-				return true, nil
-			}
-			return false, nil
+	res, err = c.client.Check(ctx, req)
+	if err == nil {
+		if res.GetStatus() == proto.HealthCheckResponse_SERVING {
+			return true, nil
 		}
-		switch grpc.Code(err) {
-		case
-			codes.Aborted,
-			codes.DataLoss,
-			codes.DeadlineExceeded,
-			codes.Internal,
-			codes.Unavailable:
-			// non-fatal errors
-		default:
-			return false, err
-		}
-		<-time.After(backoff)
+		return false, nil
 	}
+	switch grpc.Code(err) {
+	case
+		codes.Aborted,
+		codes.DataLoss,
+		codes.DeadlineExceeded,
+		codes.Internal,
+		codes.Unavailable:
+		// non-fatal errors
+	default:
+		return false, err
+	}
+
+	return false, err
 }

rpc/example/go/health/main.go

@@ -1,11 +1,12 @@
 package main
 
 import (
+	"context"
 	"log"
+	"time"
 
-	"github.com/appleboy/gorush/rpc/proto"
+	"github.com/appleboy/gorush/rpc"
 
-	"golang.org/x/net/context"
 	"google.golang.org/grpc"
 )
 
@@ -21,10 +22,16 @@ func main() {
 	}
 	defer conn.Close()
 
-	c := proto.NewHealthClient(conn)
-	r, err := c.Check(context.Background(), &proto.HealthCheckRequest{})
-	if err != nil {
-		log.Fatalf("could not greet: %v", err)
+	client := rpc.NewGrpcHealthClient(conn)
+
+	for {
+		ok, err := client.Check(context.Background())
+		if !ok || err != nil {
+			log.Printf("can't connect grpc server: %v, code: %v\n", err, grpc.Code(err))
+		} else {
+			log.Println("connect the grpc server successfully")
+		}
+
+		<-time.After(time.Second)
 	}
-	log.Printf("Health: %d\n", r.GetStatus())
 }

rpc/example/go/send/main.go

@@ -1,11 +1,11 @@
 package main
 
 import (
+	"context"
 	"log"
 
 	"github.com/appleboy/gorush/rpc/proto"
 
-	"golang.org/x/net/context"
 	"google.golang.org/grpc"
 )