Add a hermetic e2e test with fake backend pods

The test spins up an ext proc server locally with fake backend pods, sends requests, and then inspects the response headers to check the expected backend pod is selected.

It tests the code e2e except for the model server specific metric scraping code.

Author: liu-cong

pkg/ext-proc/benchmark/benchmark.go

@@ -0,0 +1,97 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"os"
+	"time"
+
+	"github.com/bojand/ghz/printer"
+	"github.com/bojand/ghz/runner"
+	"github.com/jhump/protoreflect/desc"
+	"google.golang.org/protobuf/proto"
+	klog "k8s.io/klog/v2"
+
+	"ext-proc/backend"
+	"ext-proc/test"
+)
+
+var (
+	svrAddr       = flag.String("server_address", "localhost:9002", "Address of the ext proc server")
+	totalRequests = flag.Int("total_requests", 100000, "number of requests to be sent for load test")
+	// Flags when running a local ext proc server.
+	numFakePods            = flag.Int("num_fake_pods", 200, "number of fake pods when running a local ext proc server")
+	numModelsPerPod        = flag.Int("num_models_per_pod", 5, "number of fake models per pod when running a local ext proc server")
+	localServer            = flag.Bool("local_server", true, "whether to start a local ext proc server")
+	refreshPodsInterval    = flag.Duration("refreshPodsInterval", 10*time.Second, "interval to refresh pods")
+	refreshMetricsInterval = flag.Duration("refreshMetricsInterval", 50*time.Millisecond, "interval to refresh metrics")
+)
+
+const (
+	port = 9002
+)
+
+func main() {
+	klog.InitFlags(nil)
+	flag.Parse()
+
+	if *localServer {
+		test.StartExtProc(port, *refreshPodsInterval, *refreshMetricsInterval, fakePods())
+		time.Sleep(time.Second) // wait until server is up
+		klog.Info("Server started")
+	}
+
+	report, err := runner.Run(
+		"envoy.service.ext_proc.v3.ExternalProcessor.Process",
+		*svrAddr,
+		runner.WithInsecure(true),
+		runner.WithBinaryDataFunc(generateRequest),
+		runner.WithTotalRequests(uint(*totalRequests)),
+	)
+	if err != nil {
+		klog.Fatal(err)
+	}
+
+	printer := printer.ReportPrinter{
+		Out:    os.Stdout,
+		Report: report,
+	}
+
+	printer.Print("summary")
+}
+
+func generateRequest(mtd *desc.MethodDescriptor, callData *runner.CallData) []byte {
+	numModels := *numFakePods * (*numModelsPerPod)
+	req := test.GenerateRequest(modelName(int(callData.RequestNumber) % numModels))
+	data, err := proto.Marshal(req)
+	if err != nil {
+		klog.Fatal("marshaling error: ", err)
+	}
+	return data
+}
+
+func fakePods() []*backend.PodMetrics {
+	pms := make([]*backend.PodMetrics, 0, *numFakePods)
+	for i := 0; i < *numFakePods; i++ {
+		metrics := fakeMetrics(i)
+		pod := test.FakePod(i)
+		pms = append(pms, &backend.PodMetrics{Pod: pod, Metrics: metrics})
+	}
+
+	return pms
+}
+
+// fakeMetrics adds numModelsPerPod number of adapters to the pod metrics.
+func fakeMetrics(podNumber int) backend.Metrics {
+	metrics := backend.Metrics{
+		ActiveModels: make(map[string]int),
+	}
+	for i := 0; i < *numModelsPerPod; i++ {
+		metrics.ActiveModels[modelName(podNumber*(*numModelsPerPod)+i)] = 0
+	}
+	return metrics
+}
+
+func modelName(i int) string {
+	return fmt.Sprintf("adapter-%v", i)
+}