GET and POST both are two common HTTP requests used for building REST API’s. GET requests are used to send only limited amount of data because data is sent into header while POST requests are used to send large amount of data because data is sent in the body.
Express.js facilitates you to handle GET and POST requests using the instance of express.

Express.js GET Method Example 1

Fetch data in JSON format:

Get method facilitates you to send only limited amount of data because data is sent in the header. It is not secure because data is visible in URL bar.
Let’s take an example to demonstrate GET method.

File: index.html

1. <html> 
2. <body> 
3. <form action="http://127.0.0.1:8081/process_get" method="GET"> 
4. First Name: <input type="text" name="first_name"> <br> 
5. Last Name: <input type="text" name="last_name"> 
6. <input type="submit" value="Submit"> 
7. </form> 
8. </body> 
9. </html>

File: get_example1.js

1. var express = require('express'); 
2. var app = express(); 
3. app.use(express.static('public')); 
4. 
5. app.get('/index.html', function (req, res) { 
6. res.sendFile( __dirname + "/" + "index.html" ); 
7. }) 
8. app.get('/process_get', function (req, res) { 
9. response = { 
10. first_name:req.query.first_name, 
11. last_name:req.query.last_name 
12. }; 
13. console.log(response); 
14. res.end(JSON.stringify(response)); 
15. }) 
16. var server = app.listen(8000, function () { 
17. 
18. var host = server.address().address 
19. var port = server.address().port 
20. console.log("Example app listening at http://%s:%s", host, port) 
21. 
22. })

Open the page index.html and fill the entries:

n 11

Now, you get the data in JSON format.

n 12

Express.js GET Method Example 2

Fetch data in paragraph format

File: index.html

1. <html> 
2. <body> 
3. <form action="http://127.0.0.1:8000/get_example2" method="GET"> 
4. First Name: <input type="text" name="first_name"/> <br/> 
5. Last Name: <input type="text" name="last_name"/><br/> 
6. <input type="submit" value="Submit"/> 
7. </form> 
8. </body> 
9. </html>

File: get_example2.js

1. var express = require('express'); 
2. var app=express(); 
3. app.get('/get_example2', function (req, res) { 
4. res.send('<p>Username: ' + req.query['first_name']+'</p><p>Lastname: '+req.query['last_name']+'</p>'); 
5. }) 
6. var server = app.listen(8000, function () { 
7. var host = server.address().address 
8. var port = server.address().port 
9. console.log("Example app listening at http://%s:%s", host, port) 
10. })

Open the page index.html and fill the entries:

n 13

Output:

n 14

Express.js GET Method Example 3

File:index.html

1. <!DOCTYPE html> 
2. <html> 
3. <body> 
4. <form action="http://127.0.0.1:8000/get_example3"> 
5. <table> 
6. <tr><td>Enter First Name:</td><td><input type="text" name="firstname"/><td></tr> 
7. <tr><td>Enter Last Name:</td><td><input type="text" name="lastname"/><td></tr> 
8. <tr><td>Enter Password:</td><td><input type="password" name="password"/></td></tr> 
9. <tr><td>Sex:</td><td> 
10. <input type="radio" name="sex" value="male"> Male 
11. <input type="radio" name="sex" value="female">Female 
12. </td></tr> 
13. <tr><td>About You :</td><td> 
14. <textarea rows="5" cols="40" name="aboutyou" placeholder="Write about yourself"> 
15. </textarea> 
16. </td></tr> 
17. <tr><td colspan="2"><input type="submit" value="register"/></td></tr> 
18. </table> 
19. </form> 
20. </body> 
21. </html>

File: get_example3.js

1. var express = require('express'); 
2. var app=express(); 
3. 
4. app.get('/get_example3', function (req, res) { 
5. res.send('<p>Firstname: ' + req.query['firstname']+'</p> 
6. <p>Lastname: '+req.query['lastname']+'</p><p>Password: '+req.query['password']+'</p> 
7. <p>AboutYou: '+req.query['aboutyou']+'</p>'); 
8. }) 
9. 
10. var server = app.listen(8000, function () { 
11. var host = server.address().address 
12. var port = server.address().port 
13. console.log("Example app listening at http://%s:%s", host, port) 
14. })

n 15

Express.js POST Request

GET and POST both are two common HTTP requests used for building REST API’s. POST requests are used to send large amount of data.
Express.js facilitates you to handle GET and POST requests using the instance of express.

Express.js POST Method

Post method facilitates you to send large amount of data because data is send in the body. Post method is secure because data is not visible in URL bar but it is not used as popularly as GET method. On the other hand GET method is more efficient and used more than POST.
Let’s take an example to demonstrate POST method.

Example1:

Fetch data in JSON format

File: Index.html

1. <html> 
2. <body> 
3. <form action="http://127.0.0.1:8000/process_post" method="POST"> 
4. First Name: <input type="text" name="first_name"> <br> 
5. Last Name: <input type="text" name="last_name"> 
6. <input type="submit" value="Submit"> 
7. </form> 
8. </body> 
9. </html>

File: post_example1.js

1. var express = require('express'); 
2. var app = express(); 
3. var bodyParser = require('body-parser'); 
4. // Create application/x-www-form-urlencoded parser 
5. var urlencodedParser = bodyParser.urlencoded({ extended: false }) 
6. app.use(express.static('public')); 
7. app.get('/index.html', function (req, res) { 
8. res.sendFile( __dirname + "/" + "index.html" ); 
9. }) 
10. app.post('/process_post', urlencodedParser, function (req, res) { 
11. // Prepare output in JSON format 
12. response = { 
13. first_name:req.body.first_name, 
14. last_name:req.body.last_name 
15. }; 
16. console.log(response); 
17. res.end(JSON.stringify(response)); 
18. }) 
19. var server = app.listen(8000, function () { 
20. var host = server.address().address 
21. var port = server.address().port 
22. console.log("Example app listening at http://%s:%s", host, port) 
23. })

So, this brings us to the end of blog. This Tecklearn ‘Handling GET and POST Request in NodeJS’ blog helps you with commonly asked questions if you are looking out for a job in NodeJS Programming. If you wish to learn NodeJS and build a career in NodeJS Programming domain, then check out our interactive, Node.js Training, that comes with 24*7 support to guide you throughout your learning period.

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