New integration test fixtures (#5233)

* Initial test environment implementation

* linter pass

* wip: update request latency test

* bugfixes

* Fix logic race in envoy process monitor when canceling context

* skip tests using test environment on non-linux

internal/benchmarks/latency_bench_test.go

@@ -0,0 +1,87 @@
+package benchmarks_test
+
+import (
+	"flag"
+	"fmt"
+	"io"
+	"math/rand/v2"
+	"net/http"
+	"testing"
+
+	"github.com/pomerium/pomerium/internal/testenv"
+	"github.com/pomerium/pomerium/internal/testenv/scenarios"
+	"github.com/pomerium/pomerium/internal/testenv/snippets"
+	"github.com/pomerium/pomerium/internal/testenv/upstreams"
+	"github.com/stretchr/testify/assert"
+)
+
+var (
+	numRoutes   int
+	dumpErrLogs bool
+)
+
+func init() {
+	flag.IntVar(&numRoutes, "routes", 100, "number of routes")
+	flag.BoolVar(&dumpErrLogs, "dump-err-logs", false, "if the test fails, write all captured logs to a file (testdata/<test-name>)")
+}
+
+func TestRequestLatency(t *testing.T) {
+	env := testenv.New(t, testenv.Silent())
+	users := []*scenarios.User{}
+	for i := range numRoutes {
+		users = append(users, &scenarios.User{
+			Email:     fmt.Sprintf("user%d@example.com", i),
+			FirstName: fmt.Sprintf("Firstname%d", i),
+			LastName:  fmt.Sprintf("Lastname%d", i),
+		})
+	}
+	env.Add(scenarios.NewIDP(users))
+
+	up := upstreams.HTTP(nil)
+	up.Handle("/", func(w http.ResponseWriter, _ *http.Request) {
+		w.Write([]byte("OK"))
+	})
+	routes := make([]testenv.Route, numRoutes)
+	for i := range numRoutes {
+		routes[i] = up.Route().
+			From(env.SubdomainURL(fmt.Sprintf("from-%d", i))).
+			PPL(fmt.Sprintf(`{"allow":{"and":["email":{"is":"user%d@example.com"}]}}`, i))
+	}
+	env.AddUpstream(up)
+
+	env.Start()
+	snippets.WaitStartupComplete(env)
+
+	out := testing.Benchmark(func(b *testing.B) {
+		b.ReportAllocs()
+		b.RunParallel(func(pb *testing.PB) {
+			var rec *testenv.LogRecorder
+			if dumpErrLogs {
+				rec = env.NewLogRecorder(testenv.WithSkipCloseDelay())
+			}
+			for pb.Next() {
+				idx := rand.IntN(numRoutes)
+				resp, err := up.Get(routes[idx], upstreams.AuthenticateAs(fmt.Sprintf("user%d@example.com", idx)))
+				if !assert.NoError(b, err) {
+					filename := "TestRequestLatency_err.log"
+					if dumpErrLogs {
+						rec.DumpToFile(filename)
+						b.Logf("test logs written to %s", filename)
+					}
+					return
+				}
+
+				assert.Equal(b, resp.StatusCode, 200)
+				body, err := io.ReadAll(resp.Body)
+				resp.Body.Close()
+				assert.NoError(b, err)
+				assert.Equal(b, "OK", string(body))
+			}
+		})
+	})
+
+	t.Log(out)
+	t.Logf("req/s: %f", float64(out.N)/out.T.Seconds())
+
+	env.Stop()
+}