A string 24 characters in length and only with hexadecimal letters and numbers
Example use: In MongoDb the unique id’s (ObjectId)
The string must be 24 characters long. ^ Starts of string or start of line, $ end of string or line; both dependent on the “multi-line mode”
/^{24}$/Hexadecimal uses only the letters “a to f” and the number “0 to 9”
/^[a-f0-9]{24}$/The problem: How to get the unique values from this array?
const userIds = [12, 14, 44, 12, 56, 30, 12, 14]ES6 solution
const unique = [...new Set(usersIds)]; Returns
[12, 14, 44, 56, 30]Okay in the previous post we had found the “find” tool and realised we can do so much more with it using regular expressions (regEx).
To recap a regEx is
“a sequence of symbols and characters expressing a string or pattern to be searched for within a longer piece of text.”
\d = a character 0 to 9
\w = any character a to Z and 0 to 9
\s = whitespace
Example:
\d\d\d will (using the find tool in your text editor) will highlight groups of 3 numbers in a string
\w\w\w\w\w will highlight groups of 5 characters
Notice how \w\w\w included numbers and letters
\s\s will highlight double spaces
A 4 letter word can be described as,
“a space followed by any 4 characters, followed by a space”
\s\w\w\w\w\s
Which can be rewritten as
\s\w{4}\s
But that will also include numbers. To ignore numbers
\s\w{4}[a-z]\s
Not quite there, if you are playing along you will notice that we are highlighting 4 letter words and the space before and after. What we need is to set boundaries.
\b\w{4}[a-z]\b
\b is a boundary, there are a few but for now lets stay with ‘spaces’. So with that you can find all four letter words
Part 1 of understanding regular expressions (regEx).
RegEx is not just useful when writing code ( across different languages they are broadly similar) but I have found knowing a bit allows me to quickly become a “power user” when using the find replace functions in text editors like VSCode and PHPStorm.
If you are using VSCode bring up the “find” box and have a look for the icon .*
So instead of just searching for a text string you can quickly scan more accurately.
This is a simple and quick to describe, it will even save you a bunch of typing.
$name = isset($_POST['name']) ? $_POST['name'] : 'Default name';
$name = $_POST['name'] ?? 'Default name';
Soooo much better
GitHub is brilliant…. There are loads of tutorials, video and articles out there, recently I’ve spent time filling gaps in my Git version control knowledge and something struck me as odd. Every tutorial should make it clear right from the start and reminders throughout their presentations that you
DO NOT STORE PASSWORDS, KEYS, USERNAMES, CREDENTIALS, ETC. ON GIT HUB
Why?
Because there are bastards out there who are scanning git repositories for anything that could help access secured areas or consume resources they should not.
Git does scan your repo’s and will warn you but its not in real time so be warned. Still not convinced? The image is of a free Amazon Web Service account that was set up as a learning exercise the keys where saved in a Git Repo and over the course of 3 days a free account had racked up nearly $10,000US .
What can you do, if you accidentally commit a password, key, etc? Delete the branch? Roll back?
No!
The best advice and this is also given by Git themselves is to consider your data compromised and your accounts that use the data hacked. Once again, rolling back and deleting does not work.
So reset your passwords/key etc and don’t just add a 1 at the end or swap out vowels for 12345.
How do you manage password and environment values?
Have a Google for git .gitignore or visit dotIgnore on GitHub
Again part of my breaking out of jQuery and back into vanilla JavaScript
Filter, Map and Reduce examples
const dragonEvents = [
{type: 'attack', value: 12, target: 'dorkman'},
{type: 'yawn', value: 40},
{type: 'eat', target: 'horse'},
{type: 'attack', value: 23, target: 'fluffy'},
{type: 'attack', value: 12, target: 'dorkman'},
{type: 'attack', value: 3, target: 'dorkman'},
{type: 'attack', value: 10, target: 'dorkman'}
]
const totalDamageToDorkman = dragonEvents
.filter(event => event.type === 'attack')
.filter(event => event.target === 'dorkman')
.map(event => event.value)
.reduce((prev, value) => (prev || 0) + value)
const targets = dragonEvents
.filter(event => event.target)
.map(event => event.target)
const findFluffy = dragonEvents
.filter(event => event.target === 'fluffy')
const totalAttackPoints = dragonEvents
.filter(event => event.value) // Filter out null or undefined event.value
.map(event => event.value) // Push to the new array only event.value
.reduce((total, event) => (total | 0) + event) // Sum the array
// .reduce((total, event) => { return total + event}, 0) //Does the dame thing but specifies starting value
console.log('Total:\n' + totalDamageToDorkman);
console.log(JSON.stringify(targets, null, 2));
console.log(findFluffy);
console.log(totalAttackPoints);
Tanks to Fun Fun Functions and Mattias Petter Johansson
In a previous post I was refreshing my memory with vanilla JavaScript after years of jQuery-ing, especially AJAX request and the
XMLHttpRequest()
My eyes rolled when I was reading more about it then I found fetch() ( I know its been about since 2015 and now almost universally adopted).
Fetch does what XMLHttpRequest does but in a more elegant way and DOES NOT need additional libraries as it is bundled with JavaScript. It also makes use of “promises” .
const url = "https://randomuser.me/api/?results=10";
fetch(url)
.then(function(response) {
return response.json();
})
.then(function(data) {
console.log(data.results);
})
.catch(function() {
console.log("Booo");
});
The above code queries the URL, then parses the string as JSON, then does something with the data.
It also catches errors.
Good eh?
Its looks to be easy to expand and do all manner of fetching. For example submitting a form
var form = new FormData(commentForm);
fetch( url, { method: "POST", body: form })
You can then chain .then() promises to get the desired outcomes.
For more informationA quick introduction video from Google
From Google Working with the Fetch API
Jake Archibald’s post Thats so Fetch
Scotch post The Fetch API
PHP strpos() not working as expected? It could be a “non-strict” comparison problem.
When using strpos() to determine whether a substring exists within a string the results can be misleading: Remember FALSE == 0?
Consider the following:
$quote = 'Dave rocks';
if (strpos($quote, 'Dave')) {
echo 'Dave is awesome.';
} else {
echo 'Dave is not awesome.';
}strpos() Returns position is 0 ( zero ) that is evaluated as FALSE so, “Dave is not awesome”.
Much better. In this case adding the strict comparison === ( 3 equals ) to the “if” statement asks if strpos() returns a number and is not strictly FALSE. So, “Dave is awesome”
$quote = 'Dave rocks';
if (strpos($quote, 'Dave') !== FALSE) {
echo 'Dave is awesome.';
} else {
echo 'Dave is not awesome.';
}
Pagination with Laravel (5.4 at the time of writing) is very easy.
Say you want a table of users
In your controller:
$user = User::all()->paginate(10);
In the view loop through your users as normal and then add
$user->links() where ever you feel like it and more than one place if you are feeling dandy.
But say you want more than one paginate-able list/table on the same page? This is the paginators signature
paginate($perPage = null, $columns = ['*'], $pageName = 'page', $page = null)
Easy, extending the original query lets get all the threads/comments for a user. Assuming your User model can dish out Threads and Comments
$user = User::find(1); $threads = $user->threads()->paginate(4, ['*'], 'threads'); $comments = $user->comments()->paginate(4, ['*'], 'comments');
Then in your view loop through your comments and add
$comments->links();
Loop through your threads and add
$threads->links();