first commit

pkg/grpclient/client.go

@@ -0,0 +1,98 @@
+package grpclient
+
+import (
+	"context"
+	"errors"
+	"time"
+
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/credentials"
+	"google.golang.org/grpc/credentials/insecure"
+	"google.golang.org/grpc/keepalive"
+)
+
+var (
+	defaultDialTimeout = time.Second * 2
+)
+
+type Option func(*option)
+
+type option struct {
+	credential       credentials.TransportCredentials
+	keepalive        *keepalive.ClientParameters
+	dialTimeout      time.Duration
+	unaryInterceptor grpc.UnaryClientInterceptor
+}
+
+// WithCredential setup credential for tls
+func WithCredential(credential credentials.TransportCredentials) Option {
+	return func(opt *option) {
+		opt.credential = credential
+	}
+}
+
+// WithKeepAlive setup keepalive parameters
+func WithKeepAlive(keepalive *keepalive.ClientParameters) Option {
+	return func(opt *option) {
+		opt.keepalive = keepalive
+	}
+}
+
+// WithDialTimeout set up the dial timeout
+func WithDialTimeout(timeout time.Duration) Option {
+	return func(opt *option) {
+		opt.dialTimeout = timeout
+	}
+}
+
+func WithUnaryInterceptor(unaryInterceptor grpc.UnaryClientInterceptor) Option {
+	return func(opt *option) {
+		opt.unaryInterceptor = unaryInterceptor
+	}
+}
+
+func New(target string, options ...Option) (*grpc.ClientConn, error) {
+	if target == "" {
+		return nil, errors.New("target required")
+	}
+
+	opt := new(option)
+	for _, f := range options {
+		f(opt)
+	}
+
+	kacp := defaultKeepAlive
+	if opt.keepalive != nil {
+		kacp = opt.keepalive
+	}
+
+	dialTimeout := defaultDialTimeout
+	if opt.dialTimeout > 0 {
+		dialTimeout = opt.dialTimeout
+	}
+
+	dialOptions := []grpc.DialOption{
+		grpc.WithBlock(),
+		grpc.WithKeepaliveParams(*kacp),
+	}
+
+	if opt.unaryInterceptor != nil {
+		dialOptions = append(dialOptions, grpc.WithUnaryInterceptor(opt.unaryInterceptor))
+	}
+
+	if opt.credential == nil {
+		dialOptions = append(dialOptions, grpc.WithTransportCredentials(insecure.NewCredentials()))
+	} else {
+		dialOptions = append(dialOptions, grpc.WithTransportCredentials(opt.credential))
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), dialTimeout)
+	defer cancel()
+
+	conn, err := grpc.DialContext(ctx, target, dialOptions...)
+	if err != nil {
+		return nil, err
+	}
+
+	return conn, nil
+}

pkg/grpclient/keepalive.go

@@ -0,0 +1,15 @@
+package grpclient
+
+import (
+	"time"
+
+	"google.golang.org/grpc/keepalive"
+)
+
+var (
+	defaultKeepAlive = &keepalive.ClientParameters{
+		Time:                10 * time.Second,
+		Timeout:             time.Second,
+		PermitWithoutStream: true,
+	}
+)