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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 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?

@whitequark's answer (the one with the most votes) should be marked as the correct answer. Do you mind updating it for others with the same question as you that stumble upon your question?
Use the query object in express request - here are examples using express request query
@Dev01 he is not active since 2014 lol
If anyone looking for Nodejs API boilerplate with Expressjs and MongoDB. Try this: github.com/maitraysuthar/rest-api-nodejs-mongodb
If you are confused between the terms url query and url params, you are not alone. stackoverflow.com/questions/30967822/…

c
chridam

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);

Worth mentioning that you should use req.query.id, no need to use bracket notation.
To install express do it: yes | sudo npm install -g express --- I tried to edit but Alexis King have been reverted.
in the question he was looking for a way to get all the query string parameters like an array. The correct answer is this: app.get('/', function(req, res){ console.log(req.query); });
@alex there's no advantage to using dot syntax over bracket notation. Really doesn't matter at all if you use one or the other
for url-path-params (/user/:id), use req.params.id as above answer is for url-query-params (/user?id=123)
N
Naeio

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;

attention here: .parse(url,true) url.parse(urlStr, [parseQueryString], [slashesDenoteHost])
What additional/better functionality does hapi provide ( if any ) ?
This is accepted but it's not the preferred answer. See below! use req.query
mikemcneil's answer below is a better choice. Use req.query or req.param (which is different than req.params...see below.
-1. Code above is a deadweight — something a good developer will refactor on the spot. This is an answer to "How to get the query string of an URL?" — the URL in question just happens to be in an object named request and has nothing to do with Express. See @whitequark's answer below (use request.query)
C
Ciro Santilli Путлер Капут 六四事

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)


req.param('STRING') is the correct answer. See here: stackoverflow.com/questions/17007997/… (scroll down to answer below the accepted answer)
@deltab here's a link to req.params in the Sails docs: sailsjs.org/#/documentation/reference/req/req.params.html and the new express docs: expressjs.com/4x/api.html#req.params
req.param is deprecated in express 4.x, should use req.params, req.body or req.query instead: expressjs.com/en/4x/api.html#req.param
@swang is right- I double-checked with Doug Wilson recently about this, and the req.param() helper function is likely to be completely removed in Express 5. This won't be imminent until some time later in 2017, so I'll wait to edit this answer until then. In the mean time: It's safe to use req.param() with Express <=3.x / Sails <=0.12, and with the latest available release of Express 4, albeit w/ a deprecation log message. (For Sails users: The implementation of req.param() will move into core as of Sails v1.0, and it will continue to be fully supported in Sails in the future.)
Update: Since Express is on 4.18.1 as of July 2022, you're still good to go with req.param() in Express for now, until 5.0 is released. Regardless, req.param() will always be supported in Sails.js apps. (Fixed link: sailsjs.com/documentation/reference/request-req/req-param)
P
Peter Mortensen

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

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

to retrieve GET variables in express.js you can use req.query.
@Andy req.params is better because: req.param(name[, default]) will: Return the value of param name when present or default. Checks route params (req.params), ex: /user/:id Checks query string params (req.query), ex: ?id=12Checks 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.
I didn't know req.param checks for req.query, thanks for this note.
req.param('parameterName') will check for req.body, req.query, and req.params, but if you want all of the query parameters as an object, you should use req.query.
@mikermcneil you probably mixed up req.param() and req.params (object). According to expressjs docs req.param() looks for value in all three objects. expressjs.com/api.html#req.param
P
Peter Mortensen

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

won't id and option be undefined since query is just a string? we'd have to parse out the two separate parameters with a regex or the like.
@ossek I believe the act of causing parse on req.url converts to an object.
@ossek, he's provided true as a second argument to url.parse, which makes the query property point to an object ( and that internally uses querystring module) you can find more about it in the docs [here] (nodejs.org/docs/latest/api/…)
B
Baum mit Augen
//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"}

})

Exactly what I needed, perfect answer
i
iluu

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)


Using object destructuring with default values! +1
N
Nikita Popov

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);

C
Casey Watson

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")
})

M
Mars Robertson

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)


P
Peter Mortensen

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".


you don't need to require sys in this example
P
Peter Mortensen

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'));
})

P
Peter Mortensen

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


Y
Yash Bele

You can use

request.query.<varible-name>;

d
dazed-and-confused

Express specific simple ways to fetch

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); 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);


H
Harsh Patel

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.


K
Kevin Alemán

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.


I'm using express with node so this worked perfectly for me. Thank you!
N
Nikita Popov
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.


Can you explain further how this answers the question?
And how does this parse an existing parameter list?
you may use body-parser module from node.js
L
Luke

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);

S
Sahil Rajpal

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
});

'/' won't match /api/endpoint/:id and this is otherwise identical, but less informative, than the accepted answer.
@Quentin thanks for pointing the mistake. I corrected that.
a
abcbc

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);
});

C
Codemaker

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
});

A
AmiNadimi

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) => { ......

y
ylev

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


When using curl in the shell to query the server, make sure to quote the URL. Otherwise, any ampersand (&) sign in the URL will be treated as an extra command to be executed after the curl command. This could be very frustrating, as only the first query string param will be received in the server and no error will be thrown :)
p
paliz

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);


T
Tính Ngô Quang

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
  ...