【HAVENT原创】KOA2 异常处理

KOA2 全局异常处理，首先在顶部引入下面的 错误捕捉中间件，而后在底部引用 NodeJS 未捕获异常拦截 便可。

 

注意：通常状况 错误捕捉中间件 就能完整基本的错误拦截，可是在引起未捕获异常时必须先用 NodeJS 未捕获异常拦截 以后才能捕获异常，不然会直接抛出异常，致使程序崩溃！

 

错误捕捉中间件:

/**
 * 错误捕捉中间件
 */
app.use(async(ctx, next) => {
    try {
        ctx.error = (code, message) => {
            console.log('threw error');
            if (typeof code === 'string') {
                message = code;
                code = 500;
            }

            ctx.throw(code || 500, message || '服务器错误');
        };

        await next();
    } catch (e) {
        let status = e.status || 500;
        let message = e.message || '服务器错误';
        ctx.body = { status, message };

        // 手动释放 error 事件
        ctx.app.emit('error', e, ctx);
    }
});

 

NodeJS 未捕获异常拦截:

process.on('uncaughtException', function (err) {
    console.error('An uncaught error occurred!');
    //console.error(err.stack);
    console.log(new Date(), " uncaughtException:", err.message, err.status);
});

 

抛出异常语法:

// ctx 环境变量
    // statusCode http错误码，错误码是有限制的，无效的错误码会被替换为500，错误码请看附录
    // message 异常描述，可选
    // param 异常携带的参数， 可选
    ctx.throw(statusCode [, message], [param])

 

附录：

Status Code	Constructor Name
400	BadRequest
401	Unauthorized
402	PaymentRequired
403	Forbidden
404	NotFound
405	MethodNotAllowed
406	NotAcceptable
407	ProxyAuthenticationRequired
408	RequestTimeout
409	Conflict
410	Gone
411	LengthRequired
412	PreconditionFailed
413	PayloadTooLarge
414	URITooLong
415	UnsupportedMediaType
416	RangeNotSatisfiable
417	ExpectationFailed
418	ImATeapot
421	MisdirectedRequest
422	UnprocessableEntity
423	Locked
424	FailedDependency
425	UnorderedCollection
426	UpgradeRequired
428	PreconditionRequired
429	TooManyRequests
431	RequestHeaderFieldsTooLarge
451	UnavailableForLegalReasons
500	InternalServerError
501	NotImplemented
502	BadGateway
503	ServiceUnavailable
504	GatewayTimeout
505	HTTPVersionNotSupported
506	VariantAlsoNegotiates
507	InsufficientStorage
508	LoopDetected
509	BandwidthLimitExceeded
510	NotExtended
511	NetworkAuthenticationRequired