Swagger工具错误处理程序中间件没有捕获错误

Question

概述

我的自定义errorHandler中间件没有捕获到swagger-tools请求验证程序错误。相反，swagger工具HTML错误被发送回客户端。我怎样才能让我的errorHandler中间件抓住swagger工具验证错误并相应地响应客户端？

我的预测

我很无奈，很不幸。无论我在哪里放置app.use（errorHandler）指令，swagger工具的html错误都会返回给客户端，并且我的errorHandler函数从不会捕获错误。

也许我忽略了一些对我的设置公开不正确的东西。下面是我的app.js文件，在我的app.js下面是返回给客户端的[不需要的] swagger-tools HTML错误响应。同样，尽管下面的代码只在两个地方显示，但我试图将app.use（errorHandler）逐字地（比喻性地）放在每个地方。

app.js

"use strict"; 

var swaggerTools = require("swagger-tools"); 
var compression = require("compression"); 
var app = require("express")(); 
var logger = require("./config/logger"); 
var projectConfig = require("./config/projectConfig"); 
var debug = require("debug")("app-js"); // run this to enable debug logging DEBUG=app-js node app.js 

// swaggerRouter configuration 
var options = { 
    controllers: './api/controllers', 
    useStubs: false 
}; 

// The Swagger document (require it, build it programmatically, fetch it from a URL, ...) 
var swaggerDoc = require('./api/swagger/swagger.json'); 

// compress all requests except those which have Cache-Control header with the no-transform directive 
app.use(compression()); 

// for testing 
module.exports = app; 

// global error handler 
function errorHandler(err, req, res, next, statusCode) { 
    logger.error(err); 
    debug(err); 
    if (res.headersSent) { 
     return next(err); 
    } else { 
     res.status(statusCode || 500).json(projectConfig.genericErrorResponse(statusCode || 500, err.message || err || "something blew up and the err object was undefined")); 
    } 
} 

// handles timed out requests 
function haltOnTimedout(req, res, next) { 
    if (!req.timedout) { 
     next(); 
    } else { 
     debug("\nrequest timed out!\n"); 
     next("the request timed out", null, null, null, 504); 
    } 
} 

// Initialize the Swagger middleware 
swaggerTools.initializeMiddleware(swaggerDoc, function (middleware) { 
    "use strict" 

    // Interpret Swagger resources and attach metadata to request - must be first in swagger-tools middleware chain 
    app.use(middleware.swaggerMetadata()); 

    app.use(function (req, res, next) { 
     res.header("Access-Control-Allow-Origin", "*"); // CORS should be parametrized by configuration 
     res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept"); 
     next(); 
    }); 

    // Validate Swagger requests 
    // app.use(middleware.swaggerValidator()); 

    app.use(middleware.swaggerValidator({ 
     validateResponse: false 
    })); 

    app.use(haltOnTimedout); 
    app.use(errorHandler); 

    // Route validated requests to appropriate controller 
    app.use(middleware.swaggerRouter(options)); 
}); 

app.use(haltOnTimedout); 
app.use(errorHandler); 

app.listen(projectConfig.port || process.env.PORT || 9000) 
    .on("connection", function (socket) { 
     debug("\na new cxn was made by a client.\n"); 
     socket.setTimeout(projectConfig.expressTimeout || 120000); 
    }) 

招摇工具HTML错误返回到客户端

Error: Parameter (copy) failed schema validation 
<br> &nbsp; &nbsp;at throwErrorWithCode (/Users/cuv/Documents/dev/dev-project/dev-simple/node_modules/swagger-tools/lib/validators.js:121:13) 
<br> &nbsp; &nbsp;at Object.module.exports.validateAgainstSchema (/Users/cuv/Documents/dev/dev-project/dev-simple/node_modules/swagger-tools/lib/validators.js:176:7) 
<br> &nbsp; &nbsp;at /Users/cuv/Documents/dev/dev-project/dev-simple/node_modules/swagger-tools/middleware/swagger-validator.js:143:22 
<br> &nbsp; &nbsp;at /Users/cuv/Documents/dev/dev-project/dev-simple/node_modules/async/lib/async.js:356:13 
<br> &nbsp; &nbsp;at async.forEachOf.async.eachOf (/Users/cuv/Documents/dev/dev-project/dev-simple/node_modules/async/lib/async.js:233:13) 
<br> &nbsp; &nbsp;at _asyncMap (/Users/cuv/Documents/dev/dev-project/dev-simple/node_modules/async/lib/async.js:355:9) 
<br> &nbsp; &nbsp;at Object.map (/Users/cuv/Documents/dev/dev-project/dev-simple/node_modules/async/lib/async.js:337:20) 
<br> &nbsp; &nbsp;at validateValue (/Users/cuv/Documents/dev/dev-project/dev-simple/node_modules/swagger-tools/middleware/swagger-validator.js:136:11) 
<br> &nbsp; &nbsp;at /Users/cuv/Documents/dev/dev-project/dev-simple/node_modules/swagger-tools/middleware/swagger-validator.js:343:21 
<br> &nbsp; &nbsp;at /Users/cuv/Documents/dev/dev-project/dev-simple/node_modules/async/lib/async.js:356:13 

我是运行的是什么版本？

节点：

node --version 
v6.2.2 

最新的招摇工具版本，并表示：

"swagger-tools": "^0.10.1", 
"express": "^4.12.3" 

接近

任何帮助和/或洞察如何让我的ErrorHandler中间件来捕捉和从而重写swagger-tools html错误将非常非常有用。我也在apigee社区论坛上发布了我的问题，因为它是apigee-127项目的一部分。 https://community.apigee.com/questions/29267/swagger-tools-error-handler-middleware-not-catchin.html

谢谢！

Answer 1

我看到两个问题。

起初：错误处理程序必须有4个参数，所以statusCode将被忽略。

errorHandler(err, req, res, next) // correct definition 

第二位的是

next("the request timed out", null, null, null, 504); 

错误处理的第一个参数必须是错误的对象不是字符串，那么正确的代码会

next(new Error("the request timed out")); // other args passed by closure 

有许多变种是怎么过的StatusCode。

// 1. Bad way: Pass string with delimiter 
next(new Error("the request timed out;404")); 
... 
// In error handler 
var args = err.message.split() // => args[0] = the request timed out, args[1] = 404 

// 2. Check message error text 
If (err.message == 'the request timed out') 
    statusCode = 404; 

// 3. Best way is use custom error 

更多关于自定义错误here