snapshot of https://github.com/grpc/grpc-go.git (master, 2026-09-15; blobs > 131072B omitted)

test/clienttester.go

@@ -0,0 +1,109 @@
+/*
+ * Copyright 2022 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package test
+
+import (
+	"bytes"
+	"io"
+	"net"
+	"testing"
+
+	"golang.org/x/net/http2"
+)
+
+var (
+	clientPreface = []byte(http2.ClientPreface)
+)
+
+func newClientTester(t *testing.T, conn net.Conn) *clientTester {
+	ct := &clientTester{
+		t:    t,
+		conn: conn,
+	}
+	ct.fr = http2.NewFramer(conn, conn)
+	ct.greet()
+	return ct
+}
+
+type clientTester struct {
+	t    *testing.T
+	conn net.Conn
+	fr   *http2.Framer
+}
+
+// greet() performs the necessary steps for http2 connection establishment on
+// the server side.
+func (ct *clientTester) greet() {
+	ct.wantClientPreface()
+	ct.wantSettingsFrame()
+	ct.writeSettingsFrame()
+	ct.writeSettingsAck()
+
+	for {
+		f, err := ct.fr.ReadFrame()
+		if err != nil {
+			ct.t.Errorf("error reading frame from client side: %v", err)
+		}
+		switch f := f.(type) {
+		case *http2.SettingsFrame:
+			if f.IsAck() { // HTTP/2 handshake completed.
+				return
+			}
+		default:
+			ct.t.Errorf("during greet, unexpected frame type %T", f)
+		}
+	}
+}
+
+func (ct *clientTester) wantClientPreface() {
+	preface := make([]byte, len(clientPreface))
+	if _, err := io.ReadFull(ct.conn, preface); err != nil {
+		ct.t.Errorf("Error at server-side while reading preface from client. Err: %v", err)
+	}
+	if !bytes.Equal(preface, clientPreface) {
+		ct.t.Errorf("received bogus greeting from client %q", preface)
+	}
+}
+
+func (ct *clientTester) wantSettingsFrame() {
+	frame, err := ct.fr.ReadFrame()
+	if err != nil {
+		ct.t.Errorf("error reading initial settings frame from client: %v", err)
+	}
+	_, ok := frame.(*http2.SettingsFrame)
+	if !ok {
+		ct.t.Errorf("initial frame sent from client is not a settings frame, type %T", frame)
+	}
+}
+
+func (ct *clientTester) writeSettingsFrame() {
+	if err := ct.fr.WriteSettings(); err != nil {
+		ct.t.Fatalf("Error writing initial SETTINGS frame from client to server: %v", err)
+	}
+}
+
+func (ct *clientTester) writeSettingsAck() {
+	if err := ct.fr.WriteSettingsAck(); err != nil {
+		ct.t.Fatalf("Error writing ACK of client's SETTINGS: %v", err)
+	}
+}
+
+func (ct *clientTester) writeGoAway(maxStreamID uint32, code http2.ErrCode, debugData []byte) {
+	if err := ct.fr.WriteGoAway(maxStreamID, code, debugData); err != nil {
+		ct.t.Fatalf("Error writing GOAWAY: %v", err)
+	}
+}