Change the global fetch available in local extension hosts to be the one from Electron

src/vs/platform/request/common/request.ts

@@ -203,6 +203,13 @@ function registerProxyConfigurations(scope: ConfigurationScope): void {
 				default: false,
 				description: localize('systemCertificatesV2', "Controls whether experimental loading of CA certificates from the OS should be enabled. This uses a more general approach than the default implemenation."),
 				restricted: true
+			},
+			'http.experimental.electronFetch': {
+				type: 'boolean',
+				tags: ['experimental'],
+				default: true,
+				description: localize('electronFetch', "Controls whether experimental use of Electron's fetch implementation instead of Node.js' should be enabled. All local extensions will get Electron's fetch implementation for the global fetch API."),
+				restricted: true
 			}
 		}
 	};

src/vs/workbench/api/node/extHostExtensionService.ts

@@ -101,7 +101,7 @@ export class ExtHostExtensionService extends AbstractExtHostExtensionService {
 
 		// Do this when extension service exists, but extensions are not being activated yet.
 		const configProvider = await this._extHostConfiguration.getConfigProvider();
-		await connectProxyResolver(this._extHostWorkspace, configProvider, this, this._logService, this._mainThreadTelemetryProxy, this._initData);
+		await connectProxyResolver(this._extHostWorkspace, configProvider, this, this._logService, this._mainThreadTelemetryProxy, this._initData, this._store);
 		performance.mark('code/extHost/didInitProxyResolver');
 	}
 

src/vs/workbench/api/node/proxyResolver.ts

@@ -20,6 +20,7 @@ import { ILogService, LogLevel as LogServiceLevel } from '../../../platform/log/
 import { IExtensionDescription } from '../../../platform/extensions/common/extensions.js';
 import { LogLevel, createHttpPatch, createProxyResolver, createTlsPatch, ProxySupportSetting, ProxyAgentParams, createNetPatch, loadSystemCertificates } from '@vscode/proxy-agent';
 import { AuthInfo } from '../../../platform/request/common/request.js';
+import { DisposableStore } from '../../../base/common/lifecycle.js';
 
 // ESM-uncomment-begin
 import { createRequire } from 'node:module';
@@ -31,6 +32,7 @@ const net = require('net');
 // ESM-uncomment-end
 
 const systemCertificatesV2Default = false;
+const useElectronFetchDefault = true;
 
 export function connectProxyResolver(
 	extHostWorkspace: IExtHostWorkspaceProvider,
@@ -39,7 +41,11 @@ export function connectProxyResolver(
 	extHostLogService: ILogService,
 	mainThreadTelemetry: MainThreadTelemetryShape,
 	initData: IExtensionHostInitData,
+	disposables: DisposableStore,
 ) {
+
+	patchGlobalFetch(configProvider, initData, disposables);
+
 	const useHostProxy = initData.environment.useHostProxy;
 	const doUseHostProxy = typeof useHostProxy === 'boolean' ? useHostProxy : !initData.remote.isRemote;
 	const params: ProxyAgentParams = {
@@ -94,6 +100,28 @@ export function connectProxyResolver(
 	return configureModuleLoading(extensionService, lookup);
 }
 
+function patchGlobalFetch(configProvider: ExtHostConfigProvider, initData: IExtensionHostInitData, disposables: DisposableStore) {
+	if (!initData.remote.isRemote && !(globalThis as any).__originalFetch) {
+		const originalFetch = globalThis.fetch;
+		(globalThis as any).__originalFetch = originalFetch;
+		let useElectronFetch = configProvider.getConfiguration('http').get<boolean>('experimental.electronFetch', useElectronFetchDefault);
+		disposables.add(configProvider.onDidChangeConfiguration(e => {
+			if (e.affectsConfiguration('http.experimental.electronFetch')) {
+				useElectronFetch = configProvider.getConfiguration('http').get<boolean>('experimental.electronFetch', useElectronFetchDefault);
+			}
+		}));
+		const electron = require('electron');
+		globalThis.fetch = function fetch(input: any /* RequestInfo */ | URL, init?: RequestInit) {
+			if (!useElectronFetch) {
+				return originalFetch(input, init);
+			}
+			// Support for URL: https://github.com/electron/electron/issues/43712
+			const electronInput = input instanceof URL ? input.toString() : input;
+			return electron.net.fetch(electronInput, init);
+		};
+	}
+}
+
 function createPatchedModules(params: ProxyAgentParams, resolveProxy: ReturnType<typeof createProxyResolver>) {
 
 	function mergeModules(module: any, patch: any) {