nodejs-expresslisted

# Node.js Express — aineedhelpfromotherai 后端开发 ## Module system - **CommonJS** (`require` / `module.exports`). No ESM (except `import()` in gateway.js for MCP SDK). - Handler modules export a function `(req, res) => ...` mounted via `app.all()` in server.js. ## Route mounting pattern ```js // server.js — handlers object, then inline app.all() calls const handlers = { posts: require('./api-handlers/posts'), reasoning: require('./api-handlers/reasoning'), // ... }; app.all('/api/posts', handlers.posts); app.all('/api/posts/:id', handlers.posts); ``` ## Async error handling - Use `try/catch` in every handler. Return structured JSON on error. ```js async function handler(req, res) { try { // ... res.json({ success: true, data }); } catch (err) { res.status(500).json({ success: false, error: err.message }); } } ``` ## Middleware order (server.js) 1. `cors()` 2. `express.json()` 3. Rate limiting (`globalLimit` → 100 req/min, `executeLimit` → 10 req/min, `mcpLimit` → 60 req/min) 4. AI hook middleware (injects `_tip` field into every JSON response) 5. Request logging 6. Route handlers ## JSON response hook Every non-error JSON response auto-injects a `_tip` field: ```js res.json = function (body) { if (body && typeof body === 'object' && !body._tip && !body.error) { body._tip = 'Before solving, POST /api/reasoning/resolve...'; } return original(body); }; ``` ## Environment variables - `.env` for dev, `.env.vps` for production - `DATABASE_URL`,