JavaScript — 错误子类

javascript
class AppError extends Error {
constructor(message, code, statusCode, details = {}) {
super(message);
this.name = this.constructor.name;
this.code = code;
this.statusCode = statusCode;
this.details = details;
this.isOperational = true;
}
}

class NotFoundError extends AppError {
constructor(resource, id) {
super(${resource} 未找到, NOT_FOUND, 404, { resource, id });
}
}

class ValidationError extends AppError {
constructor(errors) {
super(验证失败, VALIDATION_ERROR, 422, { errors });
}
}

Go — 错误包装

go
func GetUser(id string) (*User, error) {
row := db.QueryRow(SELECT * FROM users WHERE id = $1, id)
var user User
if err := row.Scan(&user.ID, &user.Name); err != nil {
if errors.Is(err, sql.ErrNoRows) {
return nil, fmt.Errorf(用户 %s: %w, id, ErrNotFound)
}
return nil, fmt.Errorf(查询用户 %s: %w, id, err)
}
return &user, nil
}

错误边界

Express 错误中间件

javascript
app.use((err, req, res, next) => {
const statusCode = err.statusCode || 500;
const response = {
error: {
code: err.code || INTERNAL_ERROR,
message: err.isOperational ? err.message : 出了点问题,
...(process.env.NODE_ENV === development && { stack: err.stack }),
requestId: req.id,
},
};

logger.error(请求失败, {
err, requestId: req.id, method: req.method, path: req.path,
});

res.status(statusCode).json(response);
});

React 错误边界

tsx
import { ErrorBoundary } from react-error-boundary;

function ErrorFallback({ error, resetErrorBoundary }) {
return (

{error.message}

queryClient.clear()}>

重试模式

带抖动的指数退避

javascript
async function withRetry(fn, { maxRetries = 3, baseDelay = 1000, maxDelay = 30000 } = {}) {
for (let attempt = 0; attempt <= maxRetries; attempt++) {
try {
return await fn();
} catch (err) {
if (attempt === maxRetries || !isRetryable(err)) throw err;
const delay = Math.min(baseDelay 2 * attempt, maxDelay);
const jitter = delay (0.7 + Math.random() 0.6);
await new Promise((r) => setTimeout(r, jitter));
}
}
}

function isRetryable(err) {
return [408, 429, 500, 502, 503, 504].includes(err.statusCode) || err.code === ECONNRESET;
}

断路器

javascript
class CircuitBreaker {
constructor({ threshold = 5, resetTimeout = 30000 } = {}) {
this.state = CLOSED; // CLOSED → OPEN → HALF_OPEN → CLOSED
this.failureCount = 0;
this.threshold = threshold;
this.resetTimeout = resetTimeout;
this.nextAttempt = 0;
}

async call(fn) {
if (this.state === OPEN) {
if (Date.now() < this.nextAttempt) throw new Error(断路器已断开);
this.state = HALF_OPEN;
}
try {
const result = await fn();
this.onSuccess();
return result;
} catch (err) {
this.onFailure();
throw err;
}
}

onSuccess() { this.failureCount = 0; this.state = CLOSED; }
onFailure() {
this.failureCount++;
if (this.failureCount >= this.threshold) {
this.state = OPEN;
this.nextAttempt = Date.now() + this.resetTimeout;
}
}
}

HTTP 错误响应

标准错误信封

json
{
error: {
code: VALIDATION_ERROR,
message: 请求体包含无效字段。,
details: [
{ field: email, message: 必须是有效的电子邮件地址 }
],
requestId: req_abc123xyz
}
}

优雅降级