test/integration: introduce robust harness and migrate BBR suite

test/integration/bbr/harness_test.go

@@ -0,0 +1,103 @@
+/*
+Copyright 2025 The Kubernetes 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 bbr
+
+import (
+	"context"
+	"fmt"
+	"strings"
+	"testing"
+
+	extProcPb "github.com/envoyproxy/go-control-plane/envoy/service/ext_proc/v3"
+	"github.com/stretchr/testify/require"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/credentials/insecure"
+
+	runserver "sigs.k8s.io/gateway-api-inference-extension/pkg/bbr/server"
+	logutil "sigs.k8s.io/gateway-api-inference-extension/pkg/epp/util/logging"
+	"sigs.k8s.io/gateway-api-inference-extension/test/integration"
+)
+
+var logger = logutil.NewTestLogger().V(logutil.VERBOSE)
+
+// BBRHarness encapsulates the environment for a single isolated BBR test run.
+type BBRHarness struct {
+	t      *testing.T
+	ctx    context.Context
+	Client extProcPb.ExternalProcessor_ProcessClient
+
+	// Internal handles for cleanup
+	server   *runserver.ExtProcServerRunner
+	grpcConn *grpc.ClientConn
+}
+
+// NewBBRHarness boots up an isolated BBR server on a random port.
+// streaming: determines if the BBR server runs in streaming mode or unary/buffered mode.
+func NewBBRHarness(t *testing.T, ctx context.Context, streaming bool) *BBRHarness {
+	t.Helper()
+
+	// 1. Allocate Free Port
+	tcpAddr, err := integration.GetFreePort()
+	require.NoError(t, err, "failed to acquire free port for BBR server")
+	port := tcpAddr.Port
+
+	// 2. Configure BBR Server
+	// BBR is simpler than EPP; it doesn't need a K8s Manager.
+	runner := runserver.NewDefaultExtProcServerRunner(port, false)
+	runner.SecureServing = false
+	runner.Streaming = streaming
+
+	// 3. Start Server in Background
+	serverCtx, serverCancel := context.WithCancel(ctx)
+	go func() {
+		logger.Info("Starting BBR server", "port", port, "streaming", streaming)
+		if err := runner.AsRunnable(logger.WithName("bbr-server")).Start(serverCtx); err != nil {
+			// Context cancellation is expected during teardown.
+			if !strings.Contains(err.Error(), "context canceled") {
+				logger.Error(err, "BBR server stopped unexpectedly")
+			}
+		}
+	}()
+
+	// 4. Connect Client
+	// Blocking dial ensures the server is reachable before the test logic begins.
+	addr := fmt.Sprintf("127.0.0.1:%d", port)
+	conn, err := grpc.NewClient(addr, grpc.WithTransportCredentials(insecure.NewCredentials()))
+	require.NoError(t, err, "failed to create grpc connection to BBR server")
+
+	extProcClient, err := extProcPb.NewExternalProcessorClient(conn).Process(ctx)
+	require.NoError(t, err, "failed to initialize ext_proc stream client")
+
+	h := &BBRHarness{
+		t:        t,
+		ctx:      ctx,
+		Client:   extProcClient,
+		server:   runner,
+		grpcConn: conn,
+	}
+
+	// 5. Register Cleanup
+	t.Cleanup(func() {
+		logger.Info("Tearing down BBR server", "port", port)
+		serverCancel()
+		if err := h.grpcConn.Close(); err != nil {
+			t.Logf("Warning: failed to close grpc connection: %v", err)
+		}
+	})
+
+	return h
+}