use the native node:http2 when available (#10536)

Author: vicb

.changeset/tiny-hotels-win.md

@@ -0,0 +1,7 @@
+---
+"@cloudflare/unenv-preset": patch
+---
+
+Use the native `node:http2` when available.
+
+It is enabled starting on 2025-09-01 or when the `enable_nodejs_http2_module` compatibility flag is set.

packages/unenv-preset/src/preset.ts

@@ -69,13 +69,15 @@ export function getCloudflarePreset({
 };
 
 const httpOverrides = getHttpOverrides(compat);
+const http2Overrides = getHttp2Overrides(compat);
 const osOverrides = getOsOverrides(compat);
 const fsOverrides = getFsOverrides(compat);
 
 // "dynamic" as they depend on the compatibility date and flags
 const dynamicNativeModules = [
 ...nativeModules,
 ...httpOverrides.nativeModules,
+...http2Overrides.nativeModules,
 ...osOverrides.nativeModules,
 ...fsOverrides.nativeModules,
 ];
@@ -84,6 +86,7 @@ export function getCloudflarePreset({
 const dynamicHybridModules = [
 ...hybridModules,
 ...httpOverrides.hybridModules,
+...http2Overrides.hybridModules,
 ...osOverrides.hybridModules,
 ...fsOverrides.hybridModules,
 ];
@@ -192,6 +195,42 @@ function getHttpOverrides({
 };
 }
 
+/**
+ * Returns the overrides for the `node:http2` module (unenv or workerd)
+ *
+ * The native http2 implementation:
+ * - is enabled starting from 2025-09-01
+ * - can be enabled with the "enable_nodejs_http2_module" flag
+ * - can be disabled with the "disable_nodejs_http2_module" flag
+ */
+function getHttp2Overrides({
+compatibilityDate,
+compatibilityFlags,
+}: {
+compatibilityDate: string;
+compatibilityFlags: string[];
+}): { nativeModules: string[]; hybridModules: string[] } {
+const disabledByFlag = compatibilityFlags.includes(
+"disable_nodejs_http2_module"
+);
+const enabledByFlag = compatibilityFlags.includes(
+"enable_nodejs_http2_module"
+);
+const enabledByDate = compatibilityDate >= "2025-09-01";
+
+const enabled = (enabledByFlag || enabledByDate) && !disabledByFlag;
+
+return enabled
+? {
+nativeModules: ["http2"],
+hybridModules: [],
+}
+: {
+nativeModules: [],
+hybridModules: [],
+};
+}
+
 /**
  * Returns the overrides for `node:os` (unenv or workerd)
  *

packages/wrangler/e2e/unenv-preset/preset.test.ts

@@ -99,6 +99,39 @@ const testConfigs: TestConfig[] = [
 },
 },
 ],
+// node:http2
+[
+{
+name: "http2 disabled by date",
+compatibilityDate: "2024-09-23",
+expectRuntimeFlags: {
+enable_nodejs_http2_module: false,
+},
+},
+{
+name: "http2 disabled by flag",
+compatibilityDate: "2025-09-01",
+compatibilityFlags: ["disable_nodejs_http2_module"],
+expectRuntimeFlags: {
+enable_nodejs_http2_module: false,
+},
+},
+{
+name: "http2 enabled by flag",
+compatibilityDate: "2024-09-23",
+compatibilityFlags: ["enable_nodejs_http2_module"],
+expectRuntimeFlags: {
+enable_nodejs_http2_module: true,
+},
+},
+{
+name: "http2 enabled by date",
+compatibilityDate: "2025-09-01",
+expectRuntimeFlags: {
+enable_nodejs_http2_module: true,
+},
+},
+],
 // node:os
 [
 {

packages/wrangler/e2e/unenv-preset/worker/index.ts

@@ -497,4 +497,12 @@ export const WorkerdTests: Record<string, () => void> = {
 assert.deepStrictEqual(constants.O_WRONLY, 1);
 assert.deepStrictEqual(constants.O_RDWR, 2);
 },
+
+async testHttp2() {
+const http2 = await import("node:http2");
+
+assert.strictEqual(typeof http2.createSecureServer, "function");
+assert.strictEqual(typeof http2.connect, "function");
+assert.strictEqual(http2.constants.HTTP2_HEADER_STATUS, ":status");
+},
 };