fix(proxy): Add error handling to proxy agent creation (#11538)

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

packages/core/src/config/config.ts

@@ -76,9 +76,8 @@ import { MessageBus } from '../confirmation-bus/message-bus.js';
 import { PolicyEngine } from '../policy/policy-engine.js';
 import type { PolicyEngineConfig } from '../policy/types.js';
 import type { UserTierId } from '../code_assist/types.js';
-import { ProxyAgent, setGlobalDispatcher } from 'undici';
-
 import { AgentRegistry } from '../agents/registry.js';
+import { setGlobalProxy } from '../utils/fetch.js';
 import { SubagentToolWrapper } from '../agents/subagent-tool-wrapper.js';
 
 export enum ApprovalMode {
@@ -506,7 +505,7 @@ export class Config {
     }
 
     if (this.getProxy()) {
-      setGlobalDispatcher(new ProxyAgent(this.getProxy() as string));
+      setGlobalProxy(this.getProxy() as string);
     }
     this.geminiClient = new GeminiClient(this);
     this.modelRouterService = new ModelRouterService(this);

packages/core/src/tools/web-fetch.ts

@@ -21,9 +21,12 @@ import { getErrorMessage } from '../utils/errors.js';
 import type { Config } from '../config/config.js';
 import { ApprovalMode, DEFAULT_GEMINI_FLASH_MODEL } from '../config/config.js';
 import { getResponseText } from '../utils/partUtils.js';
-import { fetchWithTimeout, isPrivateIp } from '../utils/fetch.js';
+import {
+  fetchWithTimeout,
+  isPrivateIp,
+  setGlobalProxy,
+} from '../utils/fetch.js';
 import { convert } from 'html-to-text';
-import { ProxyAgent, setGlobalDispatcher } from 'undici';
 import {
   logWebFetchFallbackAttempt,
   WebFetchFallbackAttemptEvent,
@@ -425,7 +428,7 @@ export class WebFetchTool extends BaseDeclarativeTool<
     );
     const proxy = config.getProxy();
     if (proxy) {
-      setGlobalDispatcher(new ProxyAgent(proxy as string));
+      setGlobalProxy(proxy);
     }
   }
 

packages/core/src/utils/fetch.ts

@@ -6,6 +6,7 @@
 
 import { getErrorMessage, isNodeError } from './errors.js';
 import { URL } from 'node:url';
+import { ProxyAgent, setGlobalDispatcher } from 'undici';
 
 const PRIVATE_IP_RANGES = [
   /^10\./,
@@ -55,3 +56,11 @@ export async function fetchWithTimeout(
     clearTimeout(timeoutId);
   }
 }
+
+export function setGlobalProxy(proxy: string) {
+  try {
+    setGlobalDispatcher(new ProxyAgent(proxy));
+  } catch (e) {
+    console.error(`Failed to set proxy: ${getErrorMessage(e)}`);
+  }
+}