Add tracing integration test

grafana · Nov 16, 2023 · 37a5123 · 37a5123
1 parent 7070526
commit 37a5123
Showing 1 changed file with 239 additions and 0 deletions.
diff --git a/tests/tracing_test.go b/tests/tracing_test.go
@@ -0,0 +1,239 @@
+package tests
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/dop251/goja"
+	"github.com/stretchr/testify/require"
+	"go.opentelemetry.io/otel/trace"
+
+	"github.com/grafana/xk6-browser/browser"
+	"github.com/grafana/xk6-browser/k6ext/k6test"
+	browsertrace "github.com/grafana/xk6-browser/trace"
+
+	k6lib "go.k6.io/k6/lib"
+)
+
+const html = `
+<!DOCTYPE html>
+<html>
+
+<head>
+    <title>Clickable link test</title>
+</head>
+
+<body>
+	<div class="main">
+		<h3>Click Counter</h3>
+		<button id="clickme">Click me: 0</button>
+		<h3>Type input</h3>
+		<input type="text" id="typeme">
+	</div>
+    <script>
+	var button = document.getElementById("clickme"),
+	count = 0;
+	button.onclick = function() {
+		count += 1;
+		button.innerHTML = "Click me: " + count;
+	};
+    </script>
+</body>
+
+</html>
+`
+
+// TestTracing verifies that all methods instrumented to generate
+// traces behave correctly.
+func TestTracing(t *testing.T) {
+	t.Parallel()
+
+	// Init tracing mocks
+	tracer := &mockTracer{
+		spans: make(map[string]struct{}),
+	}
+	tp := &mockTracerProvider{
+		tracer: tracer,
+	}
+	// Start test server
+	ts := httptest.NewServer(http.HandlerFunc(
+		func(w http.ResponseWriter, r *http.Request) {
+			fmt.Fprint(w, html)
+		},
+	))
+
+	// Initialize VU and browser module
+	vu := k6test.NewVU(t, k6test.WithTracerProvider(tp))
+
+	rt := vu.Runtime()
+	root := browser.New()
+	mod := root.NewModuleInstance(vu)
+	jsMod, ok := mod.Exports().Default.(*browser.JSModule)
+	require.Truef(t, ok, "unexpected default mod export type %T", mod.Exports().Default)
+	require.NoError(t, rt.Set("browser", jsMod.Browser))
+	vu.ActivateVU()
+
+	// Run the test
+	vu.StartIteration(t)
+	require.NoError(t, tracer.verifySpans("iteration"))
+	setupTestTracing(t, rt)
+
+	testCases := []struct {
+		name  string
+		js    string
+		spans []string
+	}{
+		{
+			name: "browser.newPage",
+			js:   "page = browser.newPage()",
+			spans: []string{
+				"browser.newPage",
+				"browser.newContext",
+				"browserContext.newPage",
+			},
+		},
+		{
+			name: "page.goto",
+			js:   fmt.Sprintf("page.goto('%s')", ts.URL),
+			spans: []string{
+				"page.goto",
+				fmt.Sprintf("%s/", ts.URL), // Navigation span
+			},
+		},
+		{
+			name: "web_vital",
+			js:   "sleep(100);", // Wait for async WebVitals processing
+			spans: []string{
+				"web_vital",
+			},
+		},
+		{
+			name: "page.screenshot",
+			js:   "page.screenshot();",
+			spans: []string{
+				"page.screenshot",
+			},
+		},
+		{
+			name: "locator.click",
+			js:   "page.locator('#clickme').click();",
+			spans: []string{
+				"locator.click",
+			},
+		},
+		{
+			name: "locator.type",
+			js:   "page.locator('input#typeme').type('test');",
+			spans: []string{
+				"locator.type",
+			},
+		},
+		{
+			name: "page.reload",
+			js: `await Promise.all([
+					page.waitForNavigation(),
+					page.reload(),
+			  	]);`,
+			spans: []string{
+				"page.reload",
+				"page.waitForNavigation",
+			},
+		},
+		{
+			name: "page.close",
+			js:   "page.close()",
+			spans: []string{
+				"page.close",
+			},
+		},
+	}
+
+	for _, tc := range testCases {
+		assertJSInEventLoop(t, vu, tc.js)
+		require.NoError(t, tracer.verifySpans(tc.spans...))
+	}
+}
+
+func setupTestTracing(t *testing.T, rt *goja.Runtime) {
+	t.Helper()
+
+	// Declare a global page var that we can use
+	// throughout the test cases
+	_, err := rt.RunString("var page;")
+	require.NoError(t, err)
+
+	// Set a sleep function so we can use it to wait
+	// for async WebVitals processing
+	err = rt.Set("sleep", func(d int) {
+		time.Sleep(time.Duration(d) * time.Millisecond)
+	})
+	require.NoError(t, err)
+}
+
+func assertJSInEventLoop(t *testing.T, vu *k6test.VU, js string) {
+	t.Helper()
+
+	f := fmt.Sprintf(
+		"test = async function() { %s; }",
+		js)
+
+	rt := vu.Runtime()
+	_, err := rt.RunString(f)
+	require.NoError(t, err)
+
+	test, ok := goja.AssertFunction(rt.Get("test"))
+	require.True(t, ok)
+
+	err = vu.Loop.Start(func() error {
+		_, err := test(goja.Undefined())
+		return err
+	})
+	require.NoError(t, err)
+}
+
+type mockTracerProvider struct {
+	k6lib.TracerProvider
+
+	tracer trace.Tracer
+}
+
+func (m *mockTracerProvider) Tracer(
+	name string, options ...trace.TracerOption,
+) trace.Tracer {
+	return m.tracer
+}
+
+type mockTracer struct {
+	mu    sync.Mutex
+	spans map[string]struct{}
+}
+
+func (m *mockTracer) Start(
+	ctx context.Context, spanName string, opts ...trace.SpanStartOption,
+) (context.Context, trace.Span) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+
+	m.spans[spanName] = struct{}{}
+
+	return ctx, browsertrace.NoopSpan{}
+}
+
+func (m *mockTracer) verifySpans(spanNames ...string) error {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+
+	for _, sn := range spanNames {
+		if _, ok := m.spans[sn]; !ok {
+			return fmt.Errorf("%q span was not found", sn)
+		}
+		delete(m.spans, sn)
+	}
+
+	return nil
+}