Node.js require connection inside multiple module
I have a question about the require function of Node.js, imagine we have a module that manages the connection, and many small modules that contain the routes.
An example of connection file: db.js
const mysql = require('mysql');
const connection = mysql.createConnection({
host : '127.0.0.1',
user : 'root',
password : '',
database : 'chat'
});
connection.connect(function(err) {
if (err) throw err;
});
module.exports = connection;
and one of the various files to manage the routes:
const app = express();
const router = express.Router();
const db = require('./db');
router.get('/save',function(req,res){
// some code for db
});
module.exports = router;
Imagine now to have 20 routes with the same require. How will node.js behave? How many times will my connection be created?
javascript node.js
asked Nov 19 '18 at 15:36
EugenioEugenio
153
add a comment |
I have a question about the require function of Node.js, imagine we have a module that manages the connection, and many small modules that contain the routes.
An example of connection file: db.js
const mysql = require('mysql');
const connection = mysql.createConnection({
host : '127.0.0.1',
user : 'root',
password : '',
database : 'chat'
});
connection.connect(function(err) {
if (err) throw err;
});
module.exports = connection;
and one of the various files to manage the routes:
const app = express();
const router = express.Router();
const db = require('./db');
router.get('/save',function(req,res){
// some code for db
});
module.exports = router;
Imagine now to have 20 routes with the same require. How will node.js behave? How many times will my connection be created?
javascript node.js
asked Nov 19 '18 at 15:36
EugenioEugenio
153
Good question. See: stackoverflow.com/questions/30356148/…
– lependu
Nov 19 '18 at 15:46
add a comment |
I have a question about the require function of Node.js, imagine we have a module that manages the connection, and many small modules that contain the routes.
An example of connection file: db.js
const mysql = require('mysql');
const connection = mysql.createConnection({
host : '127.0.0.1',
user : 'root',
password : '',
database : 'chat'
});
connection.connect(function(err) {
if (err) throw err;
});
module.exports = connection;
and one of the various files to manage the routes:
const app = express();
const router = express.Router();
const db = require('./db');
router.get('/save',function(req,res){
// some code for db
});
module.exports = router;
Imagine now to have 20 routes with the same require. How will node.js behave? How many times will my connection be created?
javascript node.js
asked Nov 19 '18 at 15:36
EugenioEugenio
153
I have a question about the require function of Node.js, imagine we have a module that manages the connection, and many small modules that contain the routes.
An example of connection file: db.js
const mysql = require('mysql');
const connection = mysql.createConnection({
host : '127.0.0.1',
user : 'root',
password : '',
database : 'chat'
});
connection.connect(function(err) {
if (err) throw err;
});
module.exports = connection;
and one of the various files to manage the routes:
const app = express();
const router = express.Router();
const db = require('./db');
router.get('/save',function(req,res){
// some code for db
});
module.exports = router;
Imagine now to have 20 routes with the same require. How will node.js behave? How many times will my connection be created?
javascript node.js
javascript node.js
asked Nov 19 '18 at 15:36
EugenioEugenio
153
asked Nov 19 '18 at 15:36
EugenioEugenio
153
asked Nov 19 '18 at 15:36
EugenioEugenio
153
asked Nov 19 '18 at 15:36
EugenioEugenio
153
asked Nov 19 '18 at 15:36
EugenioEugenio
153
153
Good question. See: stackoverflow.com/questions/30356148/…
– lependu
Nov 19 '18 at 15:46
add a comment |
Good question. See: stackoverflow.com/questions/30356148/…
– lependu
Nov 19 '18 at 15:46
Good question. See: stackoverflow.com/questions/30356148/…
– lependu
Nov 19 '18 at 15:46
Good question. See: stackoverflow.com/questions/30356148/…
– lependu
Nov 19 '18 at 15:46
add a comment |
1 Answer
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How many times will my connection be created?
There will be one connection, because "db.js" runs only once. The things you export get stored (module.exports) and that gets returned by every require("./db"). To verify:
require("./db") === require("./db") // true
answered Nov 19 '18 at 16:10
Jonas WilmsJonas Wilms
57.5k43051
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
How many times will my connection be created?
There will be one connection, because "db.js" runs only once. The things you export get stored (module.exports) and that gets returned by every require("./db"). To verify:
require("./db") === require("./db") // true
answered Nov 19 '18 at 16:10
Jonas WilmsJonas Wilms
57.5k43051
add a comment |
How many times will my connection be created?
There will be one connection, because "db.js" runs only once. The things you export get stored (module.exports) and that gets returned by every require("./db"). To verify:
require("./db") === require("./db") // true
answered Nov 19 '18 at 16:10
Jonas WilmsJonas Wilms
57.5k43051
add a comment |
How many times will my connection be created?
There will be one connection, because "db.js" runs only once. The things you export get stored (module.exports) and that gets returned by every require("./db"). To verify:
require("./db") === require("./db") // true
answered Nov 19 '18 at 16:10
Jonas WilmsJonas Wilms
57.5k43051
How many times will my connection be created?
There will be one connection, because "db.js" runs only once. The things you export get stored (module.exports) and that gets returned by every require("./db"). To verify:
require("./db") === require("./db") // true
answered Nov 19 '18 at 16:10
Jonas WilmsJonas Wilms
57.5k43051
answered Nov 19 '18 at 16:10
Jonas WilmsJonas Wilms
57.5k43051
answered Nov 19 '18 at 16:10
Jonas WilmsJonas Wilms
57.5k43051
answered Nov 19 '18 at 16:10
Jonas WilmsJonas Wilms
57.5k43051
57.5k43051
add a comment |
add a comment |
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Good question. See: stackoverflow.com/questions/30356148/…
– lependu
Nov 19 '18 at 15:46