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tree traversal

Nov 19, 2022CodeCatch
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Express Login Endpoint

Mar 11, 2021C S

0 likes • 4 views

router.post("/", async (req, res) => {
const { email, password } = req.body;
try {
if (!email) return res.status(400).json({ msg: "An email is required" });
if (!password)
return res.status(400).json({ msg: "A password is required" });
const user = await User.findOne({ email }).select("_id password");
if (!user) return res.status(400).json({ msg: "Invalid credentials" });
const match = await bcrypt.compare(password, user.password);
if (!match) return res.status(400).json({ msg: "Invalid credentials" });
const accessToken = genAccessToken({ id: user._id });
const refreshToken = genRefreshToken({ id: user._id });
res.cookie("token", refreshToken, {
expires: new Date(Date.now() + 604800),
httpOnly: true,
});
res.json({ accessToken });
} catch (err) {
console.log(err.message);
res.status(500).json({ msg: "Error logging in user" });
}
});

Subsets of an array

Nov 19, 2022CodeCatch

0 likes • 2 views

const getSubsets = arr => arr.reduce((prev, curr) => prev.concat(prev.map(k => k.concat(curr))), [[]]);
// Examples
getSubsets([1, 2]); // [[], [1], [2], [1, 2]]
getSubsets([1, 2, 3]); // [[], [1], [2], [1, 2], [3], [1, 3], [2, 3], [1, 2, 3]]

Check if array is empty

Nov 19, 2022CodeCatch

0 likes • 0 views

arr = [] // empty array
const isEmpty = arr => !Array.isArray(arr) || arr.length === 0;
// Examples
isEmpty([]); // true
isEmpty([1, 2, 3]); // false

localStorage Cookie Consent

Oct 9, 2023Helper

0 likes • 266 views

import React, { useState, useEffect } from 'react';
import Link from 'next/link';
export default function CookieBanner() {
// Initialize with a default value (false if not previously set in localStorage)
const [cookieConsent, setCookieConsent] = useState(() =>
localStorage.getItem('cookieConsent') === 'true' ? true : false
);
useEffect(() => {
const newCookieConsent = cookieConsent ? 'granted' : 'denied';
window.gtag('consent', 'update', {
analytics_storage: newCookieConsent
});
localStorage.setItem('cookieConsent', String(cookieConsent));
}, [cookieConsent]);
return !cookieConsent && (
<div>
<div>
<p>
We use cookies to enhance the user experience.{' '}
<Link href='/privacy/'>View privacy policy</Link>
</p>
</div>
<div>
<button type="button" onClick={() => setCookieConsent(false)}>Decline</button>
<button type="button" onClick={() => setCookieConsent(true)}>Allow</button>
</div>
</div>
)
}

Horizontal legend (d3.js)

Dec 17, 2024shaiRos

0 likes • 2 views

const rectSize = 15; // Size of the color box
const spacing = 5; // Space between legend items
let legend = canvas.append('g').attr('class','chart-legend')
.attr('transform', `translate(${0}, ${height + 3})`);
// Sample data for the legend
const legendData = [
{ label: 'low', color: '#1f77b4' },
{ label: 'medium', color: '#ff7f0e' },
{ label: 'high', color: '#2ca02c' },
{ label: 'very high', color: '#2ca02c' }
];
legend.selectAll('g')
.data(legendData)
.join('g')
.attr('class', 'legend-item')
.each(function (d, i) {
const legendItem = d3.select(this);
console.log(d.label)
console.log(d.label?.length)
let labelWidth = (d.label.length * 5) + 7 + 15
var bbox = legendItem.node().getBBox()
var width = bbox.width
console.log(width)
// Add rectangle for color
legendItem.append('rect')
.attr('width', rectSize)
.attr('height', rectSize)
.attr('fill', d.color);
// Add label
legendItem.append('text')
.attr('x', rectSize + spacing) // Position text to the right of the rectangle
.attr('y', rectSize / 2) // Align text vertically with the rectangle
.attr('dy', '.35em') // Adjust vertical alignment
.attr('text-anchor', 'start') // Align text to the start
.text(d.label)
.attr('fill', 'black'); // Optional: Text color
// legendItem.attr('transform', `translate(${i * (rectSize + spacing + labelWidth)}, 0)`) // Position each item horizontally
});
const legendItems_spacing = 12
var legendLength = 0
legend.selectAll('.legend-item').each(function(d,i) {
d3.select(this).attr('transform',function() {
var bbox = d3.select(this).node().getBBox()
var width = bbox.width
// if (width == 0) width = (d.text.length * 5) +15 // not in dom yet
let startingPosition = 0
if (i > 0) {
startingPosition = legendLength
}
legendLength += width + legendItems_spacing
// return `translate(${xx - (width + 30)},0$)`
return `translate(${startingPosition},0)`
})
})

Destructuring Assignment

Nov 19, 2022CodeCatch

0 likes • 0 views

//JavaScript program to swap two variables
//take input from the users
let a = prompt('Enter the first variable: ');
let b = prompt('Enter the second variable: ');
//using destructuring assignment
[a, b] = [b, a];
console.log(`The value of a after swapping: ${a}`);
console.log(`The value of b after swapping: ${b}`);