Laravel Pagination

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.

There is more..

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();

May 11, 2017

New querySelector() and querySelectorAll()

Catching up with JavaScript after years of using jQuery I found these two shortcuts for replacing longer getElementById() methods. NOTE: the querySelector is passed an ID in the CSS format

<button id="our-button">Add New Item</button>

<script>
    // These are both the same
    var ourButton = document.getElementById("our-button");
    var ourButton = document.querySelector("#our-button");
</script>

<ul id="our-list>
    <li>A thing</li>
    <li>Another thing</li>
    <li>A new thing</li>
</ul>


<script>
// These are both the same
   var listItems = document.getElementById('#our-list').getElementsByTagName("li");
   var listItems = document.querySelectorAll("#our-list li");
</script>

May 11, 2017

Javascript AJAX without jQuery

I learnt this stuff years ago but with the rise of jQuery I like many others had become lazy. Add the fact that so many browsers handled things slightly different going down the library route had its benefits.

It is 2017 and things have improved many jQuery(ish) approaches have been adopted by Javascript and browsers have become more similar.

So here goes. First off a GET request to retrieve a Chuck Norris joke

<script>
var url = "http://api.icndb.com/jokes/random";
var request = new XMLHttpRequest();

request.open('GET', url, true);

request.onload = function() {
 if (request.status >= 200 && request.status < 400) {
 // Success!

printJokes(request.responseText);

} else {
 // We reached our target server, but it returned an error
 console.log('There was a problem. Status:' + request.status);

}
};

request.onerror = function() {
 console.log('There was a problem!');
};

request.send();


var printJokes = function(jokes){

JSON.parse(jokes, (key, value) => {
 key == 'joke' ?
 console.log(value) : ''
 });

}
</script>

May 9, 2017

Toggling in Javascript, PHP and possibly other environments

For a long time if I wanted to change the state of a variable between true and false (toggling). In PHP I would do something like…

$switch = true;
if($switch == true){
    $switch = false;
}else{
    $switch = true
}

That worked fine, then there came Ternary shorthand

$switch = true;
$switch = ($switch == true ? false : true);

Not bad eh? Much easier to read. Then came this

$switch = true;
$switch = !$switch;

If you read it out loud it sounds like, ‘Switch is not true?’ So the answer would be either

True = $switch is false

Or

False = $switch is true

May 8, 2017

Javascript reminder #1 Spread syntax

Okay, a quick reminder on Spread Syntax

If you have a Javascript function that you call with

average(1, 2, 3);

function average(x, y, z){
// Average of the three numbers
}

You are limited to just three properties/arguments. Not very useful if you have more or less numbers you want to find an average. Using Spread Syntax we don’t have to worry about the number of values passed

function average(...args) {
  var sum = 0;
  for (let value of args) {
    sum += value;
  }
  return sum / args.length;
}

average(2, 3, 4, 5); // 3.5

The Spread Syntax ( the three dots{name}) includes all the unknown values. It gets better still

var averageMethod = 'mode';
var roundTo = 2; /Decimal places
doThing( averageMethod, [2,4,3,6,10,19], roundTo);

function doThing(method, ...valuesToAverage, roundTo)
{
// Calculate averages
}

And Spread Syntax can be used when creating arrays

var parts = ['shoulders', 'knees']; 
var lyrics = ['head', ...parts, 'and', 'toes']; 
// ["head", "shoulders", "knees", "and", "toes"]

Good eh?

March 30, 2017

Composer – Init, Install and update

Assuming that composer is installed on your machine what next?

If you do not have a composer.json file lets create one. In your command line ‘cd’ into your projects root folder. Then type

composer init

and answer the questions. Easy.

Look at your projects root directory and you will see a composer.json file. This is where you can add/remove packages, set namespaces, set files that are always load, run scripts, and lots of other good stuff.

Do you see a vendor/ directory? No? At this stage type

composer install

This actually ignores the .json file and reads or creates a composer.lock file then installs all the packages and dependencies required ( as well a bunch of other stuff – see the end of the post). The lock file is important when there are multiple developers/users it ensures that we/you are all using the exact same versions of installed packages.

Now lets pretend that you have cloned a project from GitHub that uses composer. You wont see a vendor/ directory but you will have a lock file.

composer install

Now you have a vendor/ directory and all is right with the world.

If you try and run install again it won’t do anything ( try it if you want )

If you want to add packages use the

composer require name\package

If you want to update the composer files and logs

composer update

Updates your dependencies to the latest version according to composer.json, and updates the composer.lock file.

“A bunch of other stuff”

Composer can do a whole lot more. Including

Running scripts after installing, updating, etc
Autoload files. For example helper files with common functions
Pulling packages from GitHub. Great if you are writing your own
Lets you have a development environment and production sets of packages. E.g. so you can have PHPUnit just on your local machine.

March 28, 2017

Laravel Real-Time Facades (Bastards!)

Come on Taylor Ortwell whats the deal? I spend time learning about Facades and their round-a-bout method of getting them registered and running. Now with Laravel 5.4 I can get the same outcome by typing a single line of code.

WTF?

What is a Laravel Facade?

A Facade is a “static” interface for classes that are available in the application’s service container. Think functions on steroids!

Creating them WAS simple but there where a few loops you had to jump through. But now just declare them using the Facades namespace

use Facades/{location}/{of}/DoSomething;

and use them with

DoSomething::amazing()

No need to register your Facades. Just like before DI is taken care of.

Laravel Lovelyness

In case you don’t get it I think this new method of declaring Facades is a good thing.

March 22, 2017

Laravel Validation of unique fields

Laravel Validation of unique fields e.g email

Basic server side validation in Laravel is ridiculously easy. The following inside a controller will validate the passed values and redirect back if it fails.

$this->validate($request, [

            'firstName' => 'required',

            'lastName' => 'required',

            'email' => 'required|unique:users',

            'password' => 'required|confirmed',

            ]);

You can see what fields are required; the email has to be unique in the database users table and the password is required and must match a field named ‘password_comfirm’. When this validation passes you can then add the new user.

What about UPDATING or (PUT/PATCH) the user form is returned, the firstName has changed and the email remains the same. The original validation code will not pass and return an error of ‘email already in use’.

Solution

$this->validate($request, [

            'firstName' => 'required',

            'lastName' => 'required',

            'email' => 'required|unique:users,email,'.$id.'',

            ]);

The email’s unique rule now looks up the users table, looks for the email address except where the id column matches $id

For more information: https://laravel.com/docs/5.4/validation#rule-unique

March 20, 2017

PHP Don’t Abbreviate

Simply put, please do not abbreviate in your code.

Always code as if the guy who ends up maintaining your code will be a
violent psychopath who knows where you live. Code for readability. John F Wood

If others have to read it they will have no idea what an abbreviation means and when you come back to it in 6 months time will you remember what this does?

<?php
function delHisFile($p) { 
// Do something
 }

function sort(array $a) {
 for ($i = 0, $c = count($a);  $i < $c;  $i++) { 
// Do something
 }
}

How does this read?

<?php
function deleteHistoryFiles($path) { 
// Do something
 }


function sort(array $array) {
 for ($index = 0, $array_count = count($array); $index < $array_count;  $index++) { 
// Do something
 }
}

When I started out coding for some reason I thought variables, functions, methods and class names that where long and descriptive would have an adverse effect on performance ( I know daft eh) .

March 16, 2017

PHP foreach() function

Okay, another everyday snippet of PHP code tweaked.

We all use the following

<?php

foreach($array as $item){

// Do something

}

?>

Which works fine, sometimes the // Do something gets complicated with HTML

<?php

foreach($array as $item){

echo '<tr>';

echo '<td>'.$item->first_name.'</td>';

echo '<td>'.$item->last_name.'</td>';

echo '<td><a href="'. $item->name .'">'.$item->email.'</a></td>';

echo '</tr>';

}

?>

After a while it gets messy and can be easy to have errors in your HTML which your editor might not pick up.

How about this for a solution – its an Alternative Form

<?php

foreach($array as $item) : ?>

<tr>

<td><?= $item->first_name ?></td>

<td><?= $item->last_name ?></td>

<td><a href="<?= $item->email ?>"><?= $item->email ?></a></td>

</tr>

<?php endforeach ?>

There are a few other ways but this reads really well. If you are looking to store the HTML as a variable before echoing it out have a look at ob_start(). However, creating chunks of HTML and passing them from place to another isn’t really good form – see separations of concerns and MVC

koala-moon

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