Laravel cheatsheet

The abort function throws back a specified HTTP exception.

#laravel#helper 
abort(404);
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The abort if function throws back a specified HTTP exception if the first attribute evaluates to true.

#laravel#helper 
abort_if(! auth()->check(), 403, "Unauthorized");
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The abort unless function throws back a specified HTTP exception if the first attribute evaluates to false.

#laravel#helper 
abort_if(auth()->id(), 403, "Unauthorized");
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Auth helper functions.

#laravel#auth 
auth()->id()    // Returns null if the user is not logged in or a User id if they are.
auth()->user()  // Returns a User instance.
auth()->check() // Returns boolean: true for logged in.
auth()->guest() // Returns boolean: true for a guest user.
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There are a few ways to apply the auth middleware in your project.

#laravel#auth 
// In the Controller constructor
...
    public function __constructor(){
        $this->middleware('auth') // Apply login authorization to all functions
        // or
        $this->middleware('auth')->only(['store', 'update']) // Apply login authorization only to the given functions
        // or
        $this->middleware('auth')->except(['show']) // Apply login authorization to all except the given functions
    }
...

// In the routes file you can apply Auth Middleware to specific routes
Route::get('item', 'ItemsController@index')->middleware('auth');
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Returning back function will redirect the user to the previous step.

#laravel#helper 
return back();
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Belongs to sets a single-to-single relationship between two Models. Use it for fetching a parent Model associated with your class. Pass a Model class you want to reference as an argument.

#laravel#model 
// Set the relationship in a Model file

class SubItem extends Model {
    public function item() {
        return $this->belongsTo(Item::class); // SubItem belongs to an Item
    }
}

// Then, in a Controller, you can fetch the Item your Model belongs to.  
App\SubItem::first()->item;
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In some cases you might need to clear Laravel's cache without using console. You can set up the following route and run Artisan cache clear command as a call-back function instead. In addition, follow it up with Artisan config cache command to rebuild application cache again. Then, visit the new route in your browser to trigger the Artisan commands.

#laravel#route#cache 
Route::get('/clear-cache', function() {

    $clearCache = Artisan::call('cache:clear');
    echo "Cache cleared. \r\n";

    $setCache = Artisan::call('config:cache');
    echo "Cache configured. \r\n";
});
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Compact function allows you to pass data to the view.

#laravel#view 
$color = 'blue';
$shape = 'square';

view('geometry',compact("color","shape"));
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Returns the configuration record value using the dot notation. Second argument lets you pass an optional default value.

#laravel#helper 
$appname = config('app.name', 'Default name');
// Go to the /config folder, look into the app.php file and get me the value of the 'name' record if it exists.
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Create method lets you set and persist a new item in one simple command.

#laravel 
Item::create([
    'title' => 'New item',
    'data' => 'More data'
]);
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Cross-Site Request Forgery token.

#laravel#blade 
{{ csrf_field() }}

// This returns
<input type="hidden" name="_token" value="[CSRF_HASH_TOKEN]">
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Set a default value of the record in the Migration class.

#laravel#migration#db 
$table->boolean('allowed')->default(0);
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Helpful debugging function.

#laravel 
dd($some-data);
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Add the following code to AppService provider within the boot() method. It will help with catching common errors in your production environment.

#laravel#log#debug
Reference: https://laravel.com/docs/9.x/eloquent#enabling-eloquent-strict-mode 
// public function boot()

// {

    Model::shouldBeStrict( !$this->app->isProduction() )
    
    // shouldBeStrict runs the following methods in the background

    // Model::preventLazyLoading( !$this->app->isProduction() );

    // Model::preventSilentlyDiscardingAttributes( !$this->app->isProduction() );

    // Model::preventAccessingMissingAttributes( !$this->app->isProduction() );

// }
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A helper function for raising events.

#laravel#helper 
event(new ItemWasAdded($item));
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Run Factory class in tinker to quickly generate database records. You can create multiple records in one go by passing a number of records to create as the second factory argument.

#laravel#db#factory 
factory('App\Item')->create()

// Create multiple records in one request
factory('App\Item', 10)->create()
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Faker function lets you generate dummy data for seeding the database.

#laravel#db
Reference: https://github.com/fzaninotto/Faker 
$faker = Faker\Factory::create();

$faker->name; // First and second name
$faker->randomDigit; // A random number
$faker->word; // A single word
$faker->sentence; // A sentence
$faker->unique()->word; // A single unique word
$faker->text($maxNbChars = 300); // 300 character long text
$faker->safeEmail; // An email address
$faker->hexcolor; // Hex color
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Find or fail method provides support for requests that fail to return any data from the data base. Rather than letting the app crash it captures the error and displays an in-built, user-friendly message.

#laravel 
findOrFail();

// Use case
Item::findOrFail($item);
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Set a foreign key in the data base table. Makes a reference between tables using an id and a foreign key.

#laravel#db#migration 
// Migration example
public function up(){
    Schema::create('subitems', function (Blueprint $table) {
        // Create all table fields
        $table->increments('id');
        $table->unsignedInteger('item_id');
        $table->string('text');
        $table->timestamps();
        
        // Set the foreign key
        $table->foreign('item_id')->references('id')->on('items');
        // Append the function below if you want to automatically remove all Subitems related to the Item
        // onDelete('cascade')
    });
}
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Has many sets a single-to-many relationship between two Models. Use plural form in the name of your function (subitems in this example). This is a good practice as a collection of records will be returned when the method is called. Pass a Model class you want to reference as an argument.

#laravel#model 
// Set the relationship in a Model file

class Item extends Model {
    public function subitems() {
        return $this->hasMany(SubItem::class); // Item has many SubItems
    }
}

// Then, in a Controller, you can fetch all SubItems related to the Item like so 
App\Item::first()->subitems;
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Example of joining to collections using join function helper. First argument determines a table to join, the two following arguments select columns to make the join at.

#laravel 
return DB::table('users')
->join('messages', 'messages.from', 'users.id') // Select table to join and keys to make a join at
->select('from', 'name', 'text', 'messages.created_at' )
->get();
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Navigate to the directory you want to start the new Laravel project and run the following command.

#laravel 
laravel new your-project-name
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Submit a log message to configured channels. There is eight types of messages to choose from, alert, emergency, error, critical, debug, info, notice and warning. Debug type has been used in the code example.

#laravel#log 
Log::debug($application-log);
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Method field in Laravel provides the missing support for the requests like PATCH and DELETE.

#laravel#blade 
{{ method_field('PATCH') }}

// This returns
<input type="hidden" name="_method" value="PATCH">
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Examples of passing data to a view.

#laravel#route#view 
Route::get('/', function(){
    
    // Data example
    $sections = ['Intro','Information','Stats'];

    // OPTION 1 - Pass in the second argument.
    return view('dashboard', [
        'sections' => $sections // This variable is now available in the dashboard view
        'data' => 'Some other data' // You can create multiple data holding data
    ]);

    // OPTION 2 - Using "with" magic methods.
    return view('dashboard')->withSections($sections)->withData($data);

    // OPTION 3 - Combining the two approaches above.
    return view('dashboard')->with([
        'sections' => ['Intro','Information','Stats'],
        'data' => 'Some other data'
    ]);
});
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Pluck is an eloquent helper function for narrowing down your database queries and returning a collection of specific columns.

#laravel#eloquent#db 
$item->getAllSubitems->pluck('title');
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Add the following code to AppService provider within the boot() method. This is to flag an issue when Laravel is trying to make unnecessary calls to the database. The passed attribute evaluates to a boolean and ensures the debug message doesn't display in the production environment.

#laravel#log#debug
Reference: https://laravel.com/docs/9.x/eloquent-relationships#preventing-lazy-loading 
Model::preventLazyLoading( !$this->app->isProduction() );
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This command will install only the production dependencies from your composer.json file. This is typically used when deploying application to production environments.

#laravel#composer 
composer install --no-dev
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Protected method allows to set fillable or guarded fields in the model.

#laravel#model 
class Item extends Model {
    protected $fillable = [
        'title', 'content' // Only changes to these fields ARE allowed.
    ];
}

class OtherItem extends Model {
    protected $guarded = [
        'id', 'date' // Changes to these fields ARE NOT allowed.
    ];
}
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Revert items order in the collection.

#laravel#collection 
$reversedItems = $items->reverse();
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Basic route example returning a view. Routes are located in the /routes folder of your application.

#laravel#route#view 
Route::get('/', function(){
    return view('dashboard');
});
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Use route helper to return a full url to a named route. You can pass parameters in the second argument for the dynamic parts of the url.

#laravel#helper 
route('home')
// With a single parameter
route('shop', $product->slug)
// Or an array of parameters
route('shop', ['product' => $product->slug, 'title' => $product->name])
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Using resource method will create a complete list of routes required for listing, creating, storing, editing and removing items.

#laravel#route 
Route::resource('items', 'ItemsController'); // this will generate all the routes listed below

/*
    
    // DISPLAY
        GET     /items                      ItemsController@index       Show all Items
        GET     /items/{itemID}             ItemsController@show        Show a single Item with an id of {itemsID}

    // CREATE
        GET     /items/create               ItemsController@create      Show form to create a new Item
        POST    /items                      ItemsController@store       Add new Item

    // EDIT
        GET     /items/{itemID}/edit        ItemsController@edit        Show form to edit an existing Item with an id of {itemID}
        PATCH   /items/{itemID}             ItemsController@update      Update an exiting Item with an id of {itemID}

    // REMOVE
        DELETE  /items/{itemID}             ItemsController@destroy     Delete project with an id of {itemID}

*/
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Unique function protects database from holding multiple records with the same value.

#laravel#migration#db 
// Inside of a migration
$table->string('category')->unique(); // Only one category of each type will be crated.
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Validate function allows you to set rules for the data passed in the request. If the validation fails Laravel returns an Errors object.

#laravel#controller#data 
// Controller file
public function store() {
    request()->validate([
        'FirstName' => 'required',
        'SecondName' => 'required'
    ]);
}

// View file
@if ($errors->any())
    @foreach ($errors->all() as $error)
        {{ $error }}
    @endforeach
@endif
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