fix(web): 修复生产环境 API 不可用误报

apps/web/lib/api.test.ts

@@ -0,0 +1,63 @@
+import assert from 'node:assert/strict';
+import test from 'node:test';
+
+import { __resetApiAvailabilityForTests, api, resolveApiBase } from './api';
+
+test('API base defaults to same-origin in production and localhost in development', () => {
+  assert.equal(resolveApiBase({ NODE_ENV: 'production' }), '/api/v1');
+  assert.equal(resolveApiBase({ NODE_ENV: 'development' }), 'http://localhost:3001/api/v1');
+  assert.equal(
+    resolveApiBase({ NODE_ENV: 'production', NEXT_PUBLIC_API_URL: 'https://api.example.com/api/v1/' }),
+    'https://api.example.com/api/v1',
+  );
+});
+
+test('API requests use the resolved base path', async () => {
+  const originalFetch = globalThis.fetch;
+  const apiBase = resolveApiBase();
+  const urls: string[] = [];
+
+  globalThis.fetch = (async (input: RequestInfo | URL, init?: RequestInit) => {
+    urls.push(String(input));
+    return new Response(JSON.stringify(init?.method === 'POST' ? { ok: true } : {}), {
+      status: 200,
+      headers: { 'Content-Type': 'application/json' },
+    });
+  }) as typeof fetch;
+
+  try {
+    __resetApiAvailabilityForTests();
+    await api.post('/config/ai/test', { id: 'provider-1' });
+    assert.deepEqual(urls, [`${apiBase}/config/ai`, `${apiBase}/config/ai/test`]);
+  } finally {
+    globalThis.fetch = originalFetch;
+  }
+});
+
+test('API availability probe retries after a transient failure', async () => {
+  const originalFetch = globalThis.fetch;
+  const apiBase = resolveApiBase();
+  const calls: string[] = [];
+
+  globalThis.fetch = (async (input: RequestInfo | URL, init?: RequestInit) => {
+    calls.push(String(input));
+    if (calls.length === 1) throw new Error('temporary network failure');
+    return new Response(JSON.stringify(init?.method === 'POST' ? { ok: true } : {}), {
+      status: 200,
+      headers: { 'Content-Type': 'application/json' },
+    });
+  }) as typeof fetch;
+
+  try {
+    __resetApiAvailabilityForTests();
+    await assert.rejects(() => api.post('/config/ai/test', { id: 'provider-1' }), /API 不可用/);
+    await api.post('/config/ai/test', { id: 'provider-1' });
+    assert.deepEqual(calls, [
+      `${apiBase}/config/ai`,
+      `${apiBase}/config/ai`,
+      `${apiBase}/config/ai/test`,
+    ]);
+  } finally {
+    globalThis.fetch = originalFetch;
+  }
+});