使用Express在独立节点模块中执行POST请求

Question

我正在构建一个Web应用程序，用于处理发布请求，然后对另一个服务器执行POST请求，然后根据返回的信息重定向用户。

最终结果是用户在他们的用户名和点击提交 - >应用过程后，需要用户名 - >应用程序执行发布到外部服务器包括用户名 - >服务器返回服务器的用户的URL应该开启 - >应用程序将用户重定向到该应用程序。

server.js

var express = require('express'); 
var app = express(); 
var bodyParser = require('body-parser'); 
var findUser = require('./findUserInstance') 

// Create application/x-www-form-urlencoded parser 
var urlencodedParser = bodyParser.urlencoded({ extended: false }) 

app.use(express.static('public')); 

app.get('/index.htm', function (req, res) { 
    res.sendFile(__dirname + "/" + "index.htm"); 
}) 

app.post('/process_post', urlencodedParser, function (req, res) { 

    // Prepare output in JSON format 
    response = { 
     username:req.body.username 
    }; 
    var uUrl = findUser.url(response.username); 
    console.log("redirecting to " + uUrl); 
    res.redirect(findUser.url(response.username)); 
    res.end(JSON.stringify(response)); 
}) 

var server = app.listen(8081, function() { 

    var host = server.address().address 
    var port = server.address().port 

    console.log("App listening at http://%s:%s", host, port) 

}) 

findUserInstance.js

exports.url = function(uName) { 

    var http = require("https"); 
    var uUrl; 

    var options = { 
     "method": "POST", 
     "hostname": "removed", 
     "port": null, 
     "path": "removed", 
     "headers": { 
      "appkey": "removed", 
      "content-type": "application/json", 
      "cache-control": "no-cache", 
      "Accept": "application/json", 
      "postman-token": "7d87bcf1-8e11-9717-2f6e-8150a5625acd" 
     } 
    }; 

    var req = http.request(options, function (res) { 
     var chunks = []; 

     res.on("data", function (chunk) { 
      chunks.push(chunk); 
     }); 

     res.on("end", function() { 
      var body = Buffer.concat(chunks); 
      var jsoncontent = JSON.parse(body); 
      uUrl = jsoncontent.rows[0].url; 
      console.log("The following should be: user.instance.url.com) 
      console.log(jsoncontent.rows[0].url); 
      return uUrl; //The information that I want to return to server.js 
     }); 
    }); 

    req.write(JSON.stringify({username: uName})); 
    req.end(); 
} 

问题是与从外部交模块中的信息返回到server.js模块，以便它可以执行重定向。目前，我有从函数返回的变量uUrl（正确填充了来自帖子的URL）。但是findUserInstance模块返回null。

如何从findUserInstance模块获取uUrl的值到server.js模块？

Answer 1

@bryan euton良好的反应，你应该返回findUserInstance中的任何对象像诺言！ https://developer.mozilla.org/fr/docs/Web/JavaScript/Reference/Objets_globaux/Promise

exports.url = function(uName) { 
    return new Promise(function (resolve, reject){ 

    var http = require("https"); 
    var uUrl; 

    var options = { 
     "method": "POST", 
     "hostname": "removed", 
     "port": null, 
     "path": "removed", 
     "headers": { 
     "appkey": "removed", 
     "content-type": "application/json", 
     "cache-control": "no-cache", 
     "Accept": "application/json", 
     "postman-token": "7d87bcf1-8e11-9717-2f6e-8150a5625acd" 
     } 
    }; 

    var req = http.request(options, function (res) { 
     var chunks = []; 

     res.on("data", function (chunk) { 
     chunks.push(chunk); 
     }); 

     res.on("end", function() { 
     var body = Buffer.concat(chunks); 
     var jsoncontent = JSON.parse(body); 
     uUrl = jsoncontent.rows[0].url; 
     console.log("The following should be: user.instance.url.com) 
     console.log(jsoncontent.rows[0].url); 
     resolve(uUrl); //The information resolve promise with your datas 
     }); 

    }); 

    req.write(JSON.stringify({username: uName})); 
    req.end(); 

    }); 

} 

Answer 2

是现在uurl在server.js是异步的更改处理：

app.post('/process_post', urlencodedParser, function (req, res) { 

    // Prepare output in JSON format 
    response = { 
    username:req.body.username 
    }; 

    findUser.url(response.username).then(function(uUrl){ 

    console.log("redirecting to " + uUrl); 
    res.redirect(findUser.url(response.username)); 
    res.end(JSON.stringify(response)); 

    }); 

});