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@john-doherty
john-doherty / url-to-filename.js
Last active May 23, 2024 13:49
Convert a URL into a readable filename safe string
/**
* Convert a URL into a readable filename safe string
* - sort query params
* - remove protocol
* - replace / with !
* - replace ? with !!
* - replace remaining illegal characters with -
* @example
* INPUT: convertUrlToReadableFilename('https://orcascan.com/guides/how-to-scan-barcodes-into-microsoft-excel-59fd67f9');
@john-doherty
john-doherty / local-storage-helper.js
Last active March 10, 2024 19:41
localStorage helper (takes care of casting types)
/**
* local storage helper (takes care of casting types)
*/
var localStorageHelper = {
/**
* Check if item exists in local storage.
* @param {string} key - variable name
* @return {boolean} true if key exists, otherwise false
*/
@john-doherty
john-doherty / add-query-params-to-url.js
Last active August 18, 2024 00:55
Add query string parameters to a URL in JavaScript (works with browser/node, merges duplicates and works with absolute and relative URLs)
/**
* Adds query params to existing URLs (inc merging duplicates)
* @param {string} url - src URL to modify
* @param {object} params - key/value object of params to add
* @example
* // returns /guides?tag=api
* addQueryParamsToUrl('/guides?tag=hardware', { tag:'api' })
* @example
* // returns https://orcascan.com/guides?tag=api
* addQueryParamsToUrl('https://orcascan.com/guides?tag=hardware', { tag: 'api' })
@john-doherty
john-doherty / how-to-download-a-file-with-node.js
Last active October 2, 2021 20:19
How to download a file with Node.js
var fs = require('fs-extra');
var fetch = require('node-fetch');
/**
* Download a file to disk
* @example downloadFile('https://orcascan.com', './barcode-tracking.html')
* @param {string} fileUrl - url of file to download
* @param {string} destPath - destination path
* @returns {Promise} resolves once complete, otherwise rejects
*/
@john-doherty
john-doherty / javascript-isurl.js
Created March 23, 2021 16:17
Check if a string is a URL in JavaScript
/**
* Checks if a string is a URL
* @example isUrl('https://orcascan.com') // true;
* @param {string} str - value to test
* @returns {boolean} true if URL otherwise false
*/
function isUrl(str) {
return /(ftp|http|https):\/\/(\w+:{0,1}\w*@)?(\S+)(:[0-9]+)?(\/|\/([\w#!:.?+=&%@!\-\/]))?/.test(str);
}
@john-doherty
john-doherty / javascript-is-empty.js
Last active February 19, 2021 10:51
Check if a variable is really empty in JavaScript
/**
* Checks if a JavaScript value is empty
* @example
* isEmpty(null); // true
* isEmpty(undefined); // true
* isEmpty(''); // true
* isEmpty([]); // true
* isEmpty({}); // true
* @param {any} value - item to test
* @returns {boolean} true if empty, otherwise false
@john-doherty
john-doherty / javascript-wait-for-events.js
Last active May 31, 2023 11:19
Wait for multiple JavaScript events to fire
/**
* Waits for multiple DOM events to fire
* @example
* waitForEvents(window, [
* 'DOMContentLoaded',
* 'online'
* ])
* .then(function(result) {
* // do stuff
@john-doherty
john-doherty / javascript-promises-in-sequence.js
Last active March 11, 2023 19:20
Similar to Promise.all but executes promises in sequence
/**
* Executes an array of functions that return a promise in sequence
* @example
* promisesInSequence([
* function() { return Promise.resolve(1); }
* function() { return Promise.resolve(2); },
* function() { return Promise.resolve(3); }
* ])
* .then(function(result) {
* console.log(result.join(',')); // output = 1,2,3
@john-doherty
john-doherty / puppeteer-waitforevent.js
Last active March 28, 2023 07:09
puppeteer wait for an event to fire
/**
* Wait for the browser to fire an event (including custom events)
* @param {string} eventName - Event name
* @param {integer} seconds - number of seconds to wait.
* @returns {Promise} resolves when event fires or timeout is reached
*/
async function waitForEvent(eventName, seconds) {
seconds = seconds || 30;
@john-doherty
john-doherty / get-nearest-html-attribute.js
Created August 29, 2020 14:20
Gets attribute off HTML element or nearest parent
/**
* Gets attribute off HTML element or nearest parent
* @param {object} el - HTML element to retrieve attribute from
* @param {string} attributeName - name of the attribute
* @param {any} defaultValue - default value to return if no match found
* @returns {any} attribute value or defaultValue
*/
function getNearestAttribute(el, attributeName, defaultValue) {
// walk up the dom tree looking for data-action and data-trigger