开发者

How to get GET (query string) variables in Express.js on Node.js?

Can we get the variables in the query string in Node.js开发者_开发问答 just like we get them in $_GET in PHP?

I know that in Node.js we can get the URL in the request. Is there a method to get the query string parameters?


Since you've mentioned Express.js in your tags, here is an Express-specific answer: use req.query. E.g.

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

app.get('/', function(req, res){
  res.send('id: ' + req.query.id);
});

app.listen(3000);


In Express it's already done for you and you can simply use req.query for that:

var id = req.query.id; // $_GET["id"]

Otherwise, in NodeJS, you can access req.url and the builtin url module to url.parse it manually:

var url = require('url');
var url_parts = url.parse(request.url, true);
var query = url_parts.query;


In Express, use req.query.

req.params only gets the route parameters, not the query string parameters. See the express or sails documentation:

(req.params) Checks route params, ex: /user/:id

(req.query) Checks query string params, ex: ?id=12 Checks urlencoded body params

(req.body), ex: id=12 To utilize urlencoded request bodies, req.body should be an object. This can be done by using the _express.bodyParser middleware.

That said, most of the time, you want to get the value of a parameter irrespective of its source. In that case, use req.param('foo'). Note that this has been deprecated as of Express 4: http://expressjs.com/en/4x/api.html#req.param

The value of the parameter will be returned whether the variable was in the route parameters, query string, or the encoded request body.

Side note- if you're aiming to get the intersection of all three types of request parameters (similar to PHP's $_REQUEST), you just need to merge the parameters together-- here's how I set it up in Sails. Keep in mind that the path/route parameters object (req.params) has array properties, so order matters (although this may change in Express 4)


For Express.js you want to do req.params:

app.get('/user/:id', function(req, res) {
  res.send('user' + req.params.id);    
});


I learned from the other answers and decided to use this code throughout my site:

var query = require('url').parse(req.url,true).query;

Then you can just call

var id = query.id;
var option = query.option;

where the URL for get should be

/path/filename?id=123&option=456


//get query&params in express

//etc. example.com/user/000000?sex=female

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

  const query = req.query;// query = {sex:"female"}

  const params = req.params; //params = {id:"000000"}

})


If you are using ES6 and Express, try this destructuring approach:

const {id, since, fields, anotherField} = request.query;

In context:

const express = require('express');
const app = express();

app.get('/', function(req, res){
   const {id, since, fields, anotherField} = req.query;
});

app.listen(3000);

You can use default values with destructuring too:

// sample request for testing
const req = {
  query: {
    id: '123',
    fields: ['a', 'b', 'c']
  }
}

const {
  id,
  since = new Date().toString(),
  fields = ['x'],
  anotherField = 'default'
} = req.query;

console.log(id, since, fields, anotherField)


There are 2 ways to pass parameters via GET method

Method 1 : The MVC approach where you pass the parameters like /routename/:paramname
In this case you can use req.params.paramname to get the parameter value For Example refer below code where I am expecting Id as a param
link could be like : http://myhost.com/items/23

var express = require('express');
var app = express();
app.get("items/:id", function(req, res) {
    var id = req.params.id;
    //further operations to perform
});
app.listen(3000);

Method 2 : General Approach : Passing variables as query string using '?' operator
For Example refer below code where I am expecting Id as a query parameter
link could be like : http://myhost.com/items?id=23

var express = require('express');
var app = express();
app.get("/items", function(req, res) {
    var id = req.query.id;
    //further operations to perform
});
app.listen(3000);


You should be able to do something like this:

var http = require('http');
var url  = require('url');

http.createServer(function(req,res){
    var url_parts = url.parse(req.url, true);
    var query = url_parts.query;

    console.log(query); //{Object}

    res.end("End")
})


UPDATE 4 May 2014

Old answer preserved here: https://gist.github.com/stefek99/b10ed037d2a4a323d638


1) Install express: npm install express

app.js

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

app.get('/endpoint', function(request, response) {
    var id = request.query.id;
    response.end("I have received the ID: " + id);
});

app.listen(3000);
console.log("node express app started at http://localhost:3000");

2) Run the app: node app.js

3) Visit in the browser: http://localhost:3000/endpoint?id=something

I have received the ID: something


(many things have changed since my answer and I believe it is worth keeping things up to date)


Express specific simple ways to fetch

  1. query strings(after ?) such as https://...?user=abc&id=123

     var express = require('express');
    
     var app = express();
    
     app.get('/', function(req, res){
         res.send('id: ' + req.query.id);
     });
    
     app.listen(3000);
    
  2. query params such as https://.../get/users/:id

     var express = require('express');
     var app = express();
    
     app.get('/get/users/:id', function(req, res){
         res.send('id: ' + req.params.id);
     });
    
     app.listen(3000);
    


A small Node.js HTTP server listening on port 9080, parsing GET or POST data and sending it back to the client as part of the response is:

var sys = require('sys'),
url = require('url'),
http = require('http'),
qs = require('querystring');

var server = http.createServer(

    function (request, response) {

        if (request.method == 'POST') {
                var body = '';
                request.on('data', function (data) {
                    body += data;
                });
                request.on('end',function() {

                    var POST =  qs.parse(body);
                    //console.log(POST);
                    response.writeHead( 200 );
                    response.write( JSON.stringify( POST ) );
                    response.end();
                });
        }
        else if(request.method == 'GET') {

            var url_parts = url.parse(request.url,true);
            //console.log(url_parts.query);
            response.writeHead( 200 );
            response.write( JSON.stringify( url_parts.query ) );
            response.end();
        }
    }
);

server.listen(9080);

Save it as parse.js, and run it on the console by entering "node parse.js".


Whitequark responded nicely. But with the current versions of Node.js and Express.js it requires one more line. Make sure to add the 'require http' (second line). I've posted a fuller example here that shows how this call can work. Once running, type http://localhost:8080/?name=abel&fruit=apple in your browser, and you will get a cool response based on the code.

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

app.configure(function(){
    app.set('port', 8080);
});

app.get('/', function(req, res){
  res.writeHead(200, {'content-type': 'text/plain'});
  res.write('name: ' + req.query.name + '\n');
  res.write('fruit: ' + req.query.fruit + '\n');
  res.write('query: ' + req.query + '\n');
  queryStuff = JSON.stringify(req.query);
  res.end('That\'s all folks'  + '\n' + queryStuff);
});

http.createServer(app).listen(app.get('port'), function(){
    console.log("Express server listening on port " + app.get('port'));
})


It is so simple:

Example URL:

http://stackoverflow.com:3000/activate_accountid=3&activatekey=$2a$08$jvGevXUOvYxKsiBt.PpMs.zgzD4C/wwTsvjzfUrqLrgS3zXJVfVRK

You can print all the values of query string by using:

console.log("All query strings: " + JSON.stringify(req.query));

Output

All query strings : { "id":"3","activatekey":"$2a$08$jvGevXUOvYxKsiBt.PpMs.zgzD4C/wwTsvjz fUrqLrgS3zXJVfVRK"}

To print specific:

console.log("activatekey: " + req.query.activatekey);

Output

activatekey: $2a$08$jvGevXUOvYxKsiBt.PpMs.zgzD4C/wwTsvjzfUrqLrgS3zXJVfVRK


You can use

request.query.<varible-name>;


You can use with express ^4.15.4:

var express = require('express'),
    router = express.Router();
router.get('/', function (req, res, next) {
    console.log(req.query);
});

Hope this helps.


In express.js you can get it pretty easy, all you need to do in your controller function is:

app.get('/', (req, res, next) => {
   const {id} = req.query;
   // rest of your code here...
})

And that's all, assuming you are using es6 syntax.

PD. {id} stands for Object destructuring, a new es6 feature.


app.get('/user/:id', function(req, res) {
    res.send('user' + req.params.id);    
});

You can use this or you can try body-parser for parsing special element from the request parameters.


consider this url -> /api/endpoint/:id?name=sahil here id is param where as name is query. You can get this value in nodejs like this

app.get('/api/endpoint/:id', (req, res) => {
  const name = req.query.name; // query
  const id = req.params.id //params
});


There are many answers here regarding accessing the query using request.query however, none have mentioned its type quirk. The query string type can be either a string or an array, and this type is controlled by the user.

For instance using the following code:

const express = require("express");
const app = express();

app.get("/", function (req, res) {
  res.send(`Your name is ${(req.query.name || "").length} characters long`);
});

app.listen(3000);

Requesting /?name=bob will return Your name is 3 characters long but requesting /?name=bob&name=jane will return Your name is 2 characters long because the parameter is now an array ['bob', 'jane'].

Express offers 2 query parsers: simple and extended, both will give you either a string or an array. Rather than checking a method for possible side effects or validating types, I personally think you should override the parser to have a consistent type: all arrays or all strings.

const express = require("express");
const app = express();

const querystring = require("querystring");

// if asArray=false only the first item with the same name will be returned
// if asArray=true all items will be returned as an array (even if they are a single item)
const asArray = false;
app.set("query parser", (qs) => {
  const parsed = querystring.parse(qs);
  return Object.entries(parsed).reduce((previous, [key, value]) => {
    const isArray = Array.isArray(value);
    if (!asArray && isArray) {
      value = value[0];
    } else if (asArray && !isArray) {
      value = [value];
    }

    previous[key] = value;
    return previous;
  }, {});
});

app.get("/", function (req, res) {
  res.send(`Your name is ${(req.query.name || "").length} characters long`);
});

app.listen(3000);


So, there are two ways in which this "id" can be received: 1) using params: the code params will look something like : Say we have an array,

const courses = [{
    id: 1,
    name: 'Mathematics'
},
{
    id: 2,
    name: 'History'
}
];

Then for params we can do something like:

app.get('/api/posts/:id',(req,res)=>{
    const course = courses.find(o=>o.id == (req.params.id))
    res.send(course);
});

2) Another method is to use query parameters. so the url will look something like ".....\api\xyz?id=1" where "?id=1" is the query part. In this case we can do something like:

app.get('/api/posts',(req,res)=>{
    const course = courses.find(o=>o.id == (req.query.id))
    res.send(course);
});


In case you want to avoid express, use this example:

var http = require('http');
const url = require('url');

function func111(req, res) {
  res.writeHead(200, {'Content-Type': 'text/plain'});
  var q = url.parse(req.url, true);
  res.end("9999999>>> " + q.query['user_name']); 
}

http.createServer(func111).listen(3000); 

usage:

curl http://localhost:3000?user_name=user1

by yl


you can use url module to collect parameters by using url.parse

var url = require('url');
var url_data = url.parse(request.url, true);
var query = url_data.query;

In expressjs it's done by,

var id = req.query.id;

Eg:

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

app.get('/login', function (req, res, next) {
    console.log(req.query);
    console.log(req.query.id); //Give parameter id
});


If you ever need to send GET request to an IP as well as a Domain (Other answers did not mention you can specify a port variable), you can make use of this function:

function getCode(host, port, path, queryString) {
    console.log("(" + host + ":" + port + path + ")" + "Running httpHelper.getCode()")

    // Construct url and query string
    const requestUrl = url.parse(url.format({
        protocol: 'http',
        hostname: host,
        pathname: path,
        port: port,
        query: queryString
    }));

    console.log("(" + host + path + ")" + "Sending GET request")
    // Send request
    console.log(url.format(requestUrl))
    http.get(url.format(requestUrl), (resp) => {
        let data = '';

        // A chunk of data has been received.
        resp.on('data', (chunk) => {
            console.log("GET chunk: " + chunk);
            data += chunk;
        });

        // The whole response has been received. Print out the result.
        resp.on('end', () => {
            console.log("GET end of response: " + data);
        });

    }).on("error", (err) => {
        console.log("GET Error: " + err);
    });
}

Don't miss requiring modules at the top of your file:

http = require("http");
url = require('url')

Also bare in mind that you may use https module for communicating over secured domains and ssl. so these two lines would change:

https = require("https");
...
https.get(url.format(requestUrl), (resp) => { ......


I am using MEANJS 0.6.0 with express@4.16, it's good

Client:

Controller:

var input = { keyword: vm.keyword };
ProductAPi.getOrder(input)

services:

this.getOrder = function (input) {return $http.get('/api/order', { params: input });};

Server

routes

app.route('/api/order').get(products.order);

controller

exports.order = function (req, res) {
  var keyword = req.query.keyword
  ...


do like me

npm  query-string
import queryString from "query-string";

export interface QueryUrl {
  limit?: number;
  range?: string;
  page?: number;
  filed?: string;
  embody?: string;
  q?: string | object;
  order?: number;
  sort?: string;

}

 let parseUri: QueryUrl = queryString.parse(uri.query);

0

上一篇:

下一篇:

精彩评论

暂无评论...
验证码 换一张
取 消

最新问答

问答排行榜