Question

当我在浏览器中输入somedomain.com/some_api_url?_var1=1时，回复为{"1":"descriptive string"}，其中1是一个数字索引变量，其值可以从1到{{1} }。在哪里＆＃34;描述性字符串＆＃34;是一些总结索引代表内容的文本。

如何将n api网址中的JSON response整合到下面非常简单的somedomain.com/some_api_url?_var1=1和Node.js示例中？

出于测试目的，下面显示的非常简单的Express.js将返回＆＃34; Hello World＆＃34;当用户从其Web浏览器请求app.js时。 需要对以下代码进行哪些具体更改，以便网络浏览器响应请求：

http : // localhost : 3000

而不是回复＆＃34; Hello World＆＃34;？

以下是Index is: 1 Description is: descriptive string的当前代码：

app.js

这是我当前的尝试，导致控制台打印var express = require('express'); var http = require('http'); var app = express(); app.get('/', function (req, res) { res.send('Hello World!'); }); app.listen(3000, function () { console.log('Example app listening on port 3000!'); });，并且浏览器仍然挂起，因为没有任何内容作为Got a response: undefined返回给浏览器：

response

var express = require('express'); var http = require('http'); var app = express(); app.get('/', function (req, res) { var url = 'somedomain.com/some_api_url?_var1=1'; http.get(url, function(res){ var body = ''; res.on('data', function(chunk){ body += chunk; }); res.on('end', function(){ var fbResponse = JSON.parse(body); console.log("Got a response: ", fbResponse.picture); }); }).on('error', function(e){ console.log("Got an error: ", e); }); }); app.listen(3000, function () { console.log('Example app listening on port 3000!'); });示例代码改编自the example at this link。

Answer 1

您实际上忘记返回回复res.send(data)。像这样更改端点代码。还为内部响应对象使用不同的变量名称。我在这里使用response。

app.get('/', function (req, res) {

    var url = 'somedomain.com/some_api_url?_var1=1';

    http.get(url, function(resonse){
         var body = '';

         resonse.on('data', function(chunk){
             body += chunk;
         });

         resonse.on('end', function(){
             var body = JSON.parse(body);
             var text = '';
             for (var key in body){
                  text += 'Index is: ' + key + 
                          '\nDescription is:  ' + body[key] 
             }   

// The Description is:  "descriptive string"  
             console.log("Got a response: ", fbResponse);
             res.send(text);            
         });
    }).on('error', function(e){
        console.log("Got an error: ", e);
    });

});

Answer 2

使用express 4.14.0

尝试此代码

正如@ Zohaib-Ijaz指出的那样，res被重新定义并且在没有重命名的情况下不会为res.send工作。此代码也会将其自身用于演示目的（因此您暂时可以忽略app.get('/some_api_url',。

然后，一旦完成http.get，就可以使用该对象并根据需要进行打印。请记住，此代码不能防御JSON中的错误。

var express = require('express');
var http = require('http');
var app = express();

const PORT = 3000;

app.get('/', function (req, res) {

  var url = `http://localhost:${PORT}/some_api_url?_var1=1`;

  http.get(url, function (resInner) {
    var body = '';

    resInner.on('data', function (chunk) {
      body += chunk;
    });

    resInner.on('end', function () {
      var fullResponse = JSON.parse(body); // {"343",:"I've heard 344 is more"}

      // code to pair the keys with their data in plain js
      var indexKeys = Object.keys(fullResponse);
      var replies = indexKeys.map((key) => {
        return `Index is ${key}\nDescription is ${fullResponse[key]}`;
      });

      //note this injection of a <pre> tag is just so modern browsers
      // will respect the newlines. it is not an HTML document or JSON
      res.send(
        `<pre>${replies.join("\n")}</pre>`
      );
    });
  }).on('error', function (e) {
    console.log("Got an error: ", e);
  });

});


app.get('/some_api_url', (req, res) => {
  var var1 = req.query.var1 || "343";
  var value = `I've heard ${parseInt(var1) + 1} is more`;
  var reply = {};
  reply[var1] = value;
  res.send(JSON.stringify(reply));
});

app.listen(PORT, function () {
  console.log(`Example app listening on port ${PORT}!`);
});

Answer 3

您似乎正在混淆Express，本机HTTP模块和HTTP客户端。

以下是用于发送您要查找的响应的服务器端代码。

var express = require('express');
var http = require('http');
var app = express();

// our "database"
var database = ['APPLE', 'BOOK', 'CAT', 'DOG', 'ELEPHANT'];

app.get('/', function (req, res) {

  // apply query parsing only of the query parameter is specified
  if ('itemId' in req.query) {
    var itemId = req.query.itemId;
    // index less than 0 will not yield anything from our "database"
    if (itemId < 0) {
      res.status(400).send('Invalid item id');
    // the item index corresponds to one of the items in the "database"
    } else if (itemId < database.length) {
      var result = 'Index: ' + itemId + '<br>Description: ' + database[itemId];
      res.send(result);
    // index exceeds the size of the array, so nothing will be found
    } else {
      res.status(404).send('Item not found');
    }
  // render the default homepage
  } else {
    res.send('Request format: http://localhost:3000/?itemId=n');
  }

});

app.listen(3000, function () {
  console.log('Example app listening on port 3000!');
});

要查看它的实际效果，请在浏览器中加载http://localhost:3000/?itemId=0。有效itemId值为0到4。

将JSON响应集成到Node.js / Express.js响应中

3 个答案: