tests: Add connection muiltiplexer testing

Signed-off-by: Marek Siarkowicz <siarkowicz@google.com>

tests/e2e/cmux_test.go

@@ -0,0 +1,152 @@
+// Copyright 2023 The etcd 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.
+
+// These tests are directly validating etcd connection multiplexing.
+//go:build !cluster_proxy
+
+package e2e
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	pb "go.etcd.io/etcd/etcdserver/etcdserverpb"
+	"go.etcd.io/etcd/pkg/testutil"
+)
+
+func TestConnectionMultiplexing(t *testing.T) {
+	defer testutil.AfterTest(t)
+	for _, tc := range []struct {
+		name      string
+		serverTLS clientConnType
+	}{
+		{
+			name:      "ServerTLS",
+			serverTLS: clientTLS,
+		},
+		{
+			name:      "ServerNonTLS",
+			serverTLS: clientNonTLS,
+		},
+		{
+			name:      "ServerTLSAndNonTLS",
+			serverTLS: clientTLSAndNonTLS,
+		},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			ctx := context.Background()
+			cfg := etcdProcessClusterConfig{clusterSize: 1, clientTLS: tc.serverTLS}
+			clus, err := newEtcdProcessCluster(&cfg)
+			require.NoError(t, err)
+			defer clus.Close()
+
+			var clientScenarios []clientConnType
+			switch tc.serverTLS {
+			case clientTLS:
+				clientScenarios = []clientConnType{clientTLS}
+			case clientNonTLS:
+				clientScenarios = []clientConnType{clientNonTLS}
+			case clientTLSAndNonTLS:
+				clientScenarios = []clientConnType{clientTLS, clientNonTLS}
+			}
+
+			for _, connType := range clientScenarios {
+				name := "ClientNonTLS"
+				if connType == clientTLS {
+					name = "ClientTLS"
+				}
+				t.Run(name, func(t *testing.T) {
+					testConnectionMultiplexing(ctx, t, clus.EndpointsV3()[0], connType)
+				})
+			}
+		})
+	}
+
+}
+
+func testConnectionMultiplexing(ctx context.Context, t *testing.T, endpoint string, connType clientConnType) {
+	switch connType {
+	case clientTLS:
+		endpoint = toTLS(endpoint)
+	case clientNonTLS:
+	default:
+		panic(fmt.Sprintf("Unsupported conn type %v", connType))
+	}
+	t.Run("etcdctl", func(t *testing.T) {
+		etcdctl := NewEtcdctl([]string{endpoint}, connType, false)
+		_, err := etcdctl.Get("a")
+		assert.NoError(t, err)
+	})
+	t.Run("clientv3", func(t *testing.T) {
+		c := newClient(t, []string{endpoint}, connType, false)
+		_, err := c.Get(ctx, "a")
+		assert.NoError(t, err)
+	})
+	t.Run("curl", func(t *testing.T) {
+		for _, httpVersion := range []string{"2", "1.1", "1.0", ""} {
+			tname := "http" + httpVersion
+			if httpVersion == "" {
+				tname = "default"
+			}
+			t.Run(tname, func(t *testing.T) {
+				assert.NoError(t, fetchGrpcGateway(endpoint, httpVersion, connType))
+				assert.NoError(t, fetchMetrics(endpoint, httpVersion, connType))
+				assert.NoError(t, fetchVersion(endpoint, httpVersion, connType))
+				assert.NoError(t, fetchHealth(endpoint, httpVersion, connType))
+				assert.NoError(t, fetchDebugVars(endpoint, httpVersion, connType))
+			})
+		}
+	})
+}
+
+func fetchGrpcGateway(endpoint string, httpVersion string, connType clientConnType) error {
+	rangeData, err := json.Marshal(&pb.RangeRequest{
+		Key: []byte("a"),
+	})
+	if err != nil {
+		return err
+	}
+	req := cURLReq{endpoint: "/v3/kv/range", value: string(rangeData), timeout: 5, httpVersion: httpVersion}
+	return curl(endpoint, "POST", req, connType, "header")
+}
+
+func fetchMetrics(endpoint string, httpVersion string, connType clientConnType) error {
+	req := cURLReq{endpoint: "/metrics", timeout: 5, httpVersion: httpVersion}
+	return curl(endpoint, "GET", req, connType, "etcd_cluster_version")
+}
+
+func fetchVersion(endpoint string, httpVersion string, connType clientConnType) error {
+	req := cURLReq{endpoint: "/version", timeout: 5, httpVersion: httpVersion}
+	return curl(endpoint, "GET", req, connType, "etcdserver")
+}
+
+func fetchHealth(endpoint string, httpVersion string, connType clientConnType) error {
+	req := cURLReq{endpoint: "/health", timeout: 5, httpVersion: httpVersion}
+	return curl(endpoint, "GET", req, connType, "health")
+}
+
+func fetchDebugVars(endpoint string, httpVersion string, connType clientConnType) error {
+	req := cURLReq{endpoint: "/debug/vars", timeout: 5, httpVersion: httpVersion}
+	return curl(endpoint, "GET", req, connType, "file_descriptor_limit")
+}
+
+func curl(endpoint string, method string, curlReq cURLReq, connType clientConnType, expect string) error {
+	args := cURLPrefixArgs(endpoint, connType, false, method, curlReq)
+	return spawnWithExpect(args, expect)
+}