Sometimes, we want to URl encode strings in Node.js.
In this article, we’ll look at how to URl encode strings in Node.js.
To URl encode strings in Node.js, we can call encodeURIComponent.
For instance, we write
encodeURIComponent('select * from table where uid = me()')
to call encodeURIComponent with return a string that is URI encoded.
To URl encode strings in Node.js, we can call encodeURIComponent.
Sometimes, we want to fix ‘ReferenceError: fetch is not defined’ error in Node.js.
In this article, we’ll look at how to fix ‘ReferenceError: fetch is not defined’ error in Node.js.
To fix ‘ReferenceError: fetch is not defined’ error in Node.js, we can install node-fetch.
To install it, we run
npm i node-fetch
Then we import it with
import fetch from "node-fetch";
so we can call fetch.
To fix ‘ReferenceError: fetch is not defined’ error in Node.js, we can install node-fetch.
Sometimes, we want to measure the execution time of Node.js code with callbacks.
In this article, we’ll look at how to measure the execution time of Node.js code with callbacks.
To measure the execution time of Node.js code with callbacks, we can use the process.hrtime method.
For instance, we write
let start = process.hrtime();
const elapsedTime = (note) => {
const precision = 3;
const [startTime, endTime] = process.hrtime(start)
const elapsed = endTime / 1000000;
console.log(startTime, elapsed);
start = process.hrtime();
}
to create the elaspedTime function tyat calls process.hrtime with start to return the timestamp of the elasped time and assign that to endTime.
The endTime is in nanoseconds.
So we divide endTime by 1000000 to get the elasped time in seconds.
To measure the execution time of Node.js code with callbacks, we can use the process.hrtime method.
Sometimes, we want to create a hash string with Node.js.
In this article, we’ll look at how to create a hash string with Node.js.
To create a hash string with Node.js, we can use the crypto module.
For instance, we write
const crypto = require('crypto');
const name = 'hello';
const hash = crypto.createHash('md5').update(name).digest('hex');
to call crypto.createHash with 'md5' to create a new hash string.
And we call update to create the hash string hashed from name.
Finally, we call digest with 'hex' to return the hashed string as hex.
To create a hash string with Node.js, we can use the crypto module.
Sometimes, we want to set environment variables from within package.json.
In this article, we’ll look at how to set environment variables from within package.json.
To set environment variables from within package.json, we can put the keys and values of the environment variables before the command we run.
For instance, we write
...
"scripts": {
"start": "node app.js",
"test": "NODE_ENV=test mocha --reporter spec"
},
...
to add the test script that sets the NODE_ENV environment variable to test.
And then we run the mocha command with the environment variable set.
To set environment variables from within package.json, we can put the keys and values of the environment variables before the command we run.