无法处理hystrix模块中的request-promise-json错误

我是节点js的新手，我必须在节点js中为我的项目实现hystrix弹性库，但我坚持一点。 我面临的问题是，每当我从我的服务器应用程序发送错误代码（4xx，5xx），我不能使用诺言来处理它们。 我粘贴我的app.js和server.js文件的代码。尽pipe该项目有其他几个文件，但这些文件是用于启动所有的进程，但唯一的问题是在app.js。

请帮助我如何有效地处理被拒绝的承诺错误，以便我没有得到未定义的res，身体在app.js的 isErrorHandler方法。

我还将添加控制台数据。

app.js

var express = require('express'), Promise = require('q'), request = require('request'), getRandomInt = require('./random_int'), http = require('request-promise-json'), _ = require("lodash"), hystrixStream = require('../../lib/http/HystrixSSEStream'), CommandsFactory = require("../../lib/command/CommandFactory"); var makeRequest = function(options) { var req = _.assign(options); return http.request(req); }; function hystrixStreamResponse(request, response) { response.append('Content-Type', 'text/event-stream;charset=UTF-8'); response.append('Cache-Control', 'no-cache, no-store, max-age=0, must-revalidate'); response.append('Pragma', 'no-cache'); return hystrixStream.toObservable().subscribe(function onNext(sseData) { response.write('data: ' + sseData + '\n\n'); }, function onError(error) { console.log(error); }, function onComplete() { return response.end(); }); } // called from index.js when process.env.app is set module.exports = function(port) { var app = express(), cbs = [], commands = [], reqs = 0; var isErrorHandler = function(error, res, body) { console.log("Entred error handler"); console.log("error :" + error); console.log("res:" + res); console.log("body :" + body); if (res.statusCode == 503) { console.log("Entred 503 loop"); var unavailableError = new Error(); unavailableError.name = " Service Unavailable Error.."; return unavailableError; } if (res.statusCode === 404) { console.log("Entred 404 loop"); var notFoundError = new Error(); notFoundError.name = " Avoided 404.."; return notFoundError; } if (error) { console.log("Entred default error"); return error; } return null; }; // here we are configuring all external communication points within a // command // also starting point this.configure = function(config) { config.services.forEach(function(service) { var serviceCommand = CommandsFactory.getOrCreate( "Service on port :" + service.port + ":" + port) .circuitBreakerErrorThresholdPercentage( service.errorThreshold).timeout(service.timeout) .run(makeRequest).circuitBreakerRequestVolumeThreshold( service.concurrency) .circuitBreakerSleepWindowInMilliseconds(service.timeout) .statisticalWindowLength(10000) .statisticalWindowNumberOfBuckets(10).errorHandler( isErrorHandler).build(); serviceCommand.service = service; commands.push(serviceCommand); }); }; // this is called from stats.js for hystrix Stream Response app.get('/api/hystrix.stream', hystrixStreamResponse); app.get("/", function(req, res) { var promises = []; commands.forEach(function(command) { var n = getRandomInt(1, command.service.calls); for (var i = 0; i < n; i++) { var url = "http://127.0.0.1:3003"; promises.push(command.execute(url).fail(function(error,response,body) { console.log("Entered fail error:"+error); console.log("Entered fail response:"+response); console.log("Entered fail body:"+body); //res.send(reason , res, body); }) ); } }); Promise.all(promises).then(function(results) { results.forEach(function(result) { res.send(results.join("\n")); res.set('Content-Type', 'text/plain'); reqs++; }); }).catch(function(error) { reqs++; res.send("Error: " + error); }); }); // the app.start() function is called from index.js file.. this.start = function() { // port value is passed from index.js process.title = 'node (app:' + port + ')'; app.listen(port, function() { // start variable represents when the app // started listening on a particular port var start = Date.now(); console.log("[%d] APP Listening on %d,%d", process.pid, port, process.title); // keeps calling this function after ever 1 second // reqs is a counter which keeps incrementing after every setInterval(function() { var elapsed = (Date.now() - start) / 1000; var rps = elapsed ? reqs / elapsed : 0; console.log("App req/s: " + rps + " : " + port); }, 1000); }); }; }; 

server.js

 var express = require('express'), getRandomInt = require('./random_int'); module.exports = function(port) { var app = express(), reqs = 0, sickPercentage = 20, maxSetSickTimeout = 5, sick = false, maintenancePercentage = 5, maxSetMaintenanceTimeout = 15, maintenance = false; function setSick() { sick = getRandomInt(0, 100) <= sickPercentage;// if smaller or equal // to 20 then make it // true.. console.log("SERVICE: ", port, "sick", sick); setTimeout(setSick, 1000 * getRandomInt(0, maxSetSickTimeout));//5 is max sick timeout } function setMaintenance() { // if smaller or equal to 5 then make it true..else false maintenance = getRandomInt(0, 100) <= maintenancePercentage; console.log("SERVICE: ", port, "maintenance", maintenance); setTimeout(setMaintenance, 1000 * getRandomInt(0,maxSetMaintenanceTimeout));//5 is maxSetMaintenanceTimeout } //setSick(); //setMaintenance(); app.get("/", function(req, res) { reqs++; /*if (maintenance) { res.status(503).send("Temporaly Unavailable"); return; }*/ /*var ms; if (sick) { ms = getRandomInt(0, 10 * parseInt(req.params.ms)); } else { ms = getRandomInt(0, parseInt(req.params.ms)); } setTimeout(function() { res.send("OK: slept " + ms + " ms"); }, ms);*/ (reqs % 2) == 0 ? res.status(200).send('wooohhh loving it..') :res.status(404).send("Kindly Browse more..........."); //res.status(200).send("All fine here"); return; }); this.start = function() { process.title = 'node (service:' + port + ')'; app.listen(port, function() { var start = Date.now(); console.log("[%d] SERVICE Listening on %d", process.pid, port); setInterval(function() { var elapsed = (Date.now() - start) / 1000; var rps = elapsed ? reqs / elapsed : 0; //rps=request processed per second console.log("Service req/s: " + rps+" : "+ port);//here they are printing requests processed per second process.send({ rps : rps }); }, 1000); }); }; }; /* module.exports = function(port) { var app = express(), reqs = 0, sickPercentage = 20, maxSetSickTimeout = 5, sick = false, maintenancePercentage = 5, maxSetMaintenanceTimeout = 15, maintenance = false; function setSick() { sick = getRandomInt(0, 100) <= sickPercentage;// if smaller or equal // to 20 then make it // true.. console.log("SERVICE: ", port, "sick", sick); setTimeout(setSick, 1000 * getRandomInt(0, maxSetSickTimeout));//5 is max sick timeout } function setMaintenance() { // if smaller or equal to 5 then make it true..else false maintenance = getRandomInt(0, 100) <= maintenancePercentage; console.log("SERVICE: ", port, "maintenance", maintenance); setTimeout(setMaintenance, 1000 * getRandomInt(0,maxSetMaintenanceTimeout));//5 is maxSetMaintenanceTimeout } setSick(); setMaintenance(); app.get("/random-sleep/:ms", function(req, res) { reqs++; if (maintenance) { res.status(503).send("Temporaly Unavailable"); return; } var ms; if (sick) { ms = getRandomInt(0, 10 * parseInt(req.params.ms)); } else { ms = getRandomInt(0, parseInt(req.params.ms)); } setTimeout(function() { res.send("OK: slept " + ms + " ms"); }, ms); }); this.start = function() { process.title = 'node (service:' + port + ')'; app.listen(port, function() { var start = Date.now(); console.log("[%d] SERVICE Listening on %d", process.pid, port); setInterval(function() { var elapsed = (Date.now() - start) / 1000; var rps = elapsed ? reqs / elapsed : 0; //rps=request processed per second console.log("Service req/s: " + rps);//here they are printing requests processed per second process.send({ rps : rps }); }, 1000); }); }; }; */ 

控制台输出：

 The web UI will be on http://localhost:3000/ You have 5 seconds to abort... 5... 4... 3... 2... 1... This will get a bit verbose... [932] SERVICE Listening on 3003 [5664] APP Listening on 3004,NaN Service req/s: 0 : 3003 App req/s: 0 : 3004 Service req/s: 0 : 3003 App req/s: 0 : 3004 Service req/s: 0 : 3003 App req/s: 0 : 3004 Service req/s: 0 : 3003 Entred error handler error :StatusCodeError: undefined undefined failed with status code 404 res:undefined body :undefined Entered fail error:TypeError: Cannot read property 'statusCode' of undefined Entered fail response:undefined Entered fail body:undefined App req/s: 0.2485707183693761 : 3004 Entred error handler error :StatusCodeError: undefined undefined failed with status code 404 res:undefined body :undefined Entered fail error:TypeError: Cannot read property 'statusCode' of undefined Entered fail response:undefined Entered fail body:undefined Service req/s: 0.5960659646334194 : 3003 App req/s: 0.39840637450199207 : 3004 Service req/s: 0.49677098857426727 : 3003 App req/s: 0.4980906524987548 : 3004 Service req/s: 0.5676979846721544 : 3003 Entred error handler error :StatusCodeError: undefined undefined failed with status code 404 res:undefined body :undefined Entered fail error:TypeError: Cannot read property 'statusCode' of undefined Entered fail response:undefined Entered fail body:undefined App req/s: 0.5692329585883023 : 3004 Service req/s: 0.7457121551081283 : 3003 Entred error handler error :StatusCodeError: undefined undefined failed with status code 404 res:undefined body :undefined Entered fail error:TypeError: Cannot read property 'statusCode' of undefined Entered fail response:undefined Entered fail body:undefined App req/s: 0.6222000995520159 : 3004 Entred error handler error :StatusCodeError: undefined undefined failed with status code 404 res:undefined body :undefined Entered fail error:TypeError: Cannot read property 'statusCode' of undefined Entered fail response:undefined Entered fail body:undefined Service req/s: 1.1042402826855124 : 3003 App req/s: 0.6637168141592921 : 3004 Entred error handler error :StatusCodeError: undefined undefined failed with status code 404 res:undefined body :undefined Entered fail error:TypeError: Cannot read property 'statusCode' of undefined Entered fail response:undefined Entered fail body:undefined Entred error handler error :StatusCodeError: undefined undefined failed with status code 404 res:undefined body :undefined Entered fail error:TypeError: Cannot read property 'statusCode' of undefined Entered fail response:undefined Entered fail body:undefined Service req/s: 1.29366106080207 : 3003 Entred error handler error :StatusCodeError: undefined undefined failed with status code 404 res:undefined body :undefined Entered fail error:TypeError: Cannot read property 'statusCode' of undefined Entered fail response:undefined Entered fail body:undefined App req/s: 0.9960159362549802 : 3004 Entred error handler error :StatusCodeError: undefined undefined failed with status code 404 res:undefined body :undefined Entered fail error:TypeError: Cannot read property 'statusCode' of undefined Entered fail response:undefined Entered fail body:undefined Entred error handler error :StatusCodeError: undefined undefined failed with status code 404 res:undefined body :undefined Entered fail error:TypeError: Cannot read property 'statusCode' of undefined Entered fail response:undefined Entered fail body:undefined Entred error handler error :StatusCodeError: undefined undefined failed with status code 404 res:undefined body :undefined Entered fail error:TypeError: Cannot read property 'statusCode' of undefined Entered fail response:undefined Entered fail body:undefined Service req/s: 1.9009685887571286 : 3003 Entred error handler error :StatusCodeError: undefined undefined failed with status code 404 res:undefined body :undefined Entered fail error:TypeError: Cannot read property 'statusCode' of undefined Entered fail response:undefined Entered fail body:undefined Entred error handler error :StatusCodeError: undefined undefined failed with status code 404 res:undefined body :undefined Entered fail error:TypeError: Cannot read property 'statusCode' of undefined Entered fail response:undefined Entered fail body:undefined App req/s: 1.4508523757707652 : 3004 Entred error handler error :StatusCodeError: undefined undefined failed with status code 404 res:undefined body :undefined Entered fail error:TypeError: Cannot read property 'statusCode' of undefined Entered fail response:undefined Entered fail body:undefined Entred error handler error :StatusCodeError: undefined undefined failed with status code 404 res:undefined body :undefined Entered fail error:TypeError: Cannot read property 'statusCode' of undefined Entered fail response:undefined Entered fail body:undefined Service req/s: 2.4896265560165975 : 3003 Entred error handler error :StatusCodeError: undefined undefined failed with status code 404 res:undefined body :undefined Entered fail error:TypeError: Cannot read property 'statusCode' of undefined Entered fail response:undefined Entered fail body:undefined Entred error handler error :StatusCodeError: undefined undefined failed with status code 404 res:undefined body :undefined Entered fail error:TypeError: Cannot read property 'statusCode' of undefined Entered fail response:undefined Entered fail body:undefined Entred error handler error :StatusCodeError: undefined undefined failed with status code 404 res:undefined body :undefined Entered fail error:TypeError: Cannot read property 'statusCode' of undefined Entered fail response:undefined Entered fail body:undefined App req/s: 1.8281535648994514 : 3004 Service req/s: 2.6813759289052324 : 3003 App req/s: 1.686987194233571 : 3004 Service req/s: 2.4903941938238225 : 3003 App req/s: 1.566728386269762 : 3004 

如果我没有错，那么问题是只处理承诺，执行请求返回4xx，5xx错误..