feat(datagen): add HTTP method, path, protocol, and status code pools

internal/datagen/http.go

@@ -0,0 +1,51 @@
+package datagen
+
+import "math/rand"
+
+// HTTP data pools for log generation.
+var (
+	// Methods is a pool of standard HTTP methods.
+	Methods = NewPool("GET", "POST", "PUT", "DELETE", "PATCH", "HEAD", "OPTIONS")
+
+	// Protocols is a pool of HTTP protocol versions.
+	Protocols = NewPool("HTTP/1.0", "HTTP/1.1", "HTTP/2.0")
+
+	// Status code pools grouped by class.
+	Status2xx = NewPool(200, 201, 202, 204)
+	Status3xx = NewPool(301, 302, 304, 307, 308)
+	Status4xx = NewPool(400, 401, 403, 404, 405, 408, 429)
+	Status5xx = NewPool(500, 502, 503, 504)
+
+	// APIPaths is a pool of common API and web paths.
+	APIPaths = NewPool(
+		"/api/v1/users", "/api/v1/orders", "/api/v1/products",
+		"/api/v1/auth/login", "/api/v1/auth/logout", "/api/v1/auth/refresh",
+		"/api/v2/data", "/api/v2/search", "/api/v2/metrics",
+		"/health", "/healthz", "/ready", "/status",
+		"/", "/about", "/contact", "/dashboard", "/settings",
+		"/login", "/logout", "/register", "/profile",
+		"/search", "/download", "/upload",
+	)
+
+	// RefererDomains is a pool of domains used in HTTP referer headers.
+	RefererDomains = NewPool(
+		"google.com", "bing.com", "github.com", "stackoverflow.com",
+		"reddit.com", "linkedin.com", "example.com", "internal.corp",
+	)
+)
+
+// RandomStatusCode returns a weighted random HTTP status code.
+// Distribution: ~70% 2xx, ~5% 3xx, ~15% 4xx, ~10% 5xx.
+func RandomStatusCode(r *rand.Rand) int {
+	roll := r.Float64() // #nosec G404
+	switch {
+	case roll < 0.70:
+		return Status2xx.Random(r)
+	case roll < 0.75:
+		return Status3xx.Random(r)
+	case roll < 0.90:
+		return Status4xx.Random(r)
+	default:
+		return Status5xx.Random(r)
+	}
+}

internal/datagen/http_test.go

@@ -0,0 +1,99 @@
+package datagen
+
+import (
+	"math/rand"
+	"testing"
+)
+
+func TestHTTPMethods(t *testing.T) {
+	expected := map[string]bool{
+		"GET": true, "POST": true, "PUT": true, "DELETE": true,
+		"PATCH": true, "HEAD": true, "OPTIONS": true,
+	}
+	for _, m := range Methods.All() {
+		if !expected[m] {
+			t.Errorf("unexpected HTTP method: %q", m)
+		}
+	}
+	if Methods.Len() != 7 {
+		t.Errorf("expected 7 methods, got %d", Methods.Len())
+	}
+}
+
+func TestHTTPProtocols(t *testing.T) {
+	if Protocols.Len() < 3 {
+		t.Errorf("expected at least 3 protocols, got %d", Protocols.Len())
+	}
+}
+
+func TestHTTPStatusPools(t *testing.T) {
+	if Status2xx.Len() < 3 {
+		t.Errorf("Status2xx has %d items, want at least 3", Status2xx.Len())
+	}
+	if Status3xx.Len() < 3 {
+		t.Errorf("Status3xx has %d items, want at least 3", Status3xx.Len())
+	}
+	if Status4xx.Len() < 5 {
+		t.Errorf("Status4xx has %d items, want at least 5", Status4xx.Len())
+	}
+	if Status5xx.Len() < 3 {
+		t.Errorf("Status5xx has %d items, want at least 3", Status5xx.Len())
+	}
+}
+
+func TestAPIPaths(t *testing.T) {
+	if APIPaths.Len() < 15 {
+		t.Errorf("APIPaths has %d items, want at least 15", APIPaths.Len())
+	}
+}
+
+func TestRefererDomains(t *testing.T) {
+	if RefererDomains.Len() < 5 {
+		t.Errorf("RefererDomains has %d items, want at least 5", RefererDomains.Len())
+	}
+}
+
+func TestRandomStatusCode(t *testing.T) {
+	r := rand.New(rand.NewSource(42))
+
+	counts := map[string]int{
+		"2xx": 0,
+		"3xx": 0,
+		"4xx": 0,
+		"5xx": 0,
+	}
+	for i := 0; i < 10000; i++ {
+		code := RandomStatusCode(r)
+		switch {
+		case code >= 200 && code < 300:
+			counts["2xx"]++
+		case code >= 300 && code < 400:
+			counts["3xx"]++
+		case code >= 400 && code < 500:
+			counts["4xx"]++
+		case code >= 500 && code < 600:
+			counts["5xx"]++
+		default:
+			t.Errorf("unexpected status code: %d", code)
+		}
+	}
+
+	// Verify rough distribution: 70% 2xx, 5% 3xx, 15% 4xx, 10% 5xx
+	total := 10000.0
+	if float64(counts["2xx"])/total < 0.60 {
+		t.Errorf("2xx should be ~70%%, got %.1f%%", float64(counts["2xx"])/total*100)
+	}
+	if float64(counts["5xx"])/total < 0.05 {
+		t.Errorf("5xx should be ~10%%, got %.1f%%", float64(counts["5xx"])/total*100)
+	}
+}
+
+func TestRandomStatusCodeDeterministic(t *testing.T) {
+	r1 := rand.New(rand.NewSource(99))
+	r2 := rand.New(rand.NewSource(99))
+	for i := 0; i < 50; i++ {
+		if RandomStatusCode(r1) != RandomStatusCode(r2) {
+			t.Fatal("same seed should produce same status codes")
+		}
+	}
+}