Using multiple boot traits with the same event will fire just the first one and ignore the rest bootable traits.
class Tag extends Model
{
use HasKey; // this will work (but if i put it bellow it will not work)
use HasSlug; // this's not (but if i put it above it will work)
}
trait HasKey
{
public static function bootHasKey()
{
static::creating(
fn (Model $model) => $model->key = 'value'
);
}
trait HasSlug
{
public static function bootHasSlug()
{
static::creating(
fn (Model $model) => $model->slug = 'value'
);
}
}
I found that it's not supported at the moment, maybe in the future releases of Laravel!
https://github.com/laravel/framework/issues/40645#issuecomment-1022969116
Related
Recently I'm having problems with using traits, I created some before and it seemed to work, but now I created another one to take action on a creating event, here it is
trait Contributes
{
public static function bootContributes()
{
static::creating(function ($model) {
if (!$model->getKey())
{
Contribution::create([
'contributing_id' => $model->id,
'contributing_type' => $model->class_table,
]);
}
});
}
}
and I included it in multiple models like use Contributes; I think there is something I don't know about it.
I tried dd($model); inside the trait, it works outside of the event but not inside the event
Instead of the above method, I figured this one is a better practice and works a lot more better with laravel:
public static function boot()
{
self::created(
function($model)
{
Contribution::create([
'contributing_id' => $model->id,
'contributing_type' => $model->table
]);
}
);
}
When I read the Laravel 5.3's source code, I find the following codes
public function withGlobalScope($identifier, $scope)
{
$this->scopes[$identifier] = $scope;
if (method_exists($scope, 'extend')) {
$scope->extend($this);
}
return $this;
}
I am confused about why it is the following codes in the method, is it used anywhere?
if (method_exists($scope, 'extend')) {
$scope->extend($this);
}
Thanks!
It's meant for extending the Builder within the context of a Scope class.
Inside a global Scope (class which extends the Scope interface), you can create an extend function next to the apply function.
This extend function is called with the Eloquent builder as parameter. Imagine some PopularUsersScope, which only gets very popular users:
public function apply(Builder $builder, Model $model): void
{
$builder->join(...)->where(...) // determine popularity
}
public function extend(Builder $builder)
{
$builder->macro('demote', function (Builder $builder) {
return $builder->update(...) // query to make user not so popular
});
}
Now lets have a model Clan, which is a group of users, some of which are popular. We have a constrained relation on Clan:
public function popular_users(): belongsToMany
{
return $this->hasMany(User::class)
->withGlobalScope('popularUsers', new PopularUsersScope)
}
Because we defined a macro within the scope extend function, we can do $user->demote() for any popular user, but not for normal users.
This might be a bit of a silly example, but it can be useful in fairly abstract use cases.
See SoftDeletingScope in the Laravel Framework code for a practical example: SoftDeletable items need some extra methods on the Builder for restoring and eager loading deleted items.
Extend in SoftDeletingScope dynamically adds multiple extensions to the Builder, from an Array $this->extensions, and registers an replacement for the default delete function on the model:
public function extend(Builder $builder)
{
foreach ($this->extensions as $extension) {
$this->{"add{$extension}"}($builder);
}
$builder->onDelete(function (Builder $builder) {
$column = $this->getDeletedAtColumn($builder);
return $builder->update([
$column => $builder->getModel()->freshTimestampString(),
]);
});
}
In Laravel 4, query scopes are available on all queries (including ones generated by relations queries). This means that for the following (example) models:
Customer.php:
<?php
class Customer extends Eloquent {
public function order() { return $this->hasMany('Order'); }
}
Order.php:
<?php
class Order extends Eloquent {
public function scopeDelivered($query) { return $query->where('delivered', '=', true); }
public function customer() { return $this->belongsTo('Customer'); }
}
Both of the following work:
var_dump(Order::delivered()->get()); // All delivered orders
var_dump(Customer::find(1)->orders()->delivered()->get()); // only orders by customer #1 that are delivered
This is useful from within a controller because the query logic for finding delivered orders doesn't have to be repeated.
Recently, though, I've been convinced that the Repository pattern is optimal for not only separation of concerns but also for the possibility of a ORM/DB switch or the necessity of adding middleware like a cache. Repositories feel very natural, because now instead of having scopes bloat my models, the associated queries are instead part of the Repository (which makes more sense because naturally this would be a method of the collection not the item).
For example,
<?php
class EloquentOrderRepository {
protected $order;
public function __construct(Order $order) { $this->order = $order; }
public function find($id) { /* ... */ }
/* etc... */
public function allDelievered() { return $this->order->where('delivered', '=', true)->get(); }
}
However, now I have the delivered scope repeated, so to avoid violating DRY, I remove it from the model (which seems logical as per the justification above). But now, I can no longer can use scopes on relations (like $customer->orders()->delivered()). The only workaround here I see is somehow instantiating the Repository with the pre-made query (similar to what is passed to the scopes in the models) in the Relation base class. But this involves changing (and overriding) a lot of code and default behavior and seems to make things more coupled than they should be.
Given this dilemma, is this is misuse of a repository? If not, is my solution the only way to regain the functionality that I would like? Or is having the scopes in the models not tight enough coupling to justify this extra code? If the scopes aren't tight coupling, then is there a way to use both the Repository pattern and scopes while still being DRY?
Note: I am aware of some similar questions on similar topics but none of them address the issue presented here with queries generated by relationships, which do not rely on the Repository.
I've managed to find a solution. It's rather hacky and I'm not sure whether I consider it acceptable (it uses a lot of things in ways that they likely weren't meant to be used). To summarize, the solution allows you to move scopes to the repository. Each repository (on instantiation) is booted once, and during this process all of the scope methods are extracted and added to each query created by the eloquent model (via macros) by way of a Illuminate\Database\Eloquent\ScopeInterface.
The (Hack-y) solution
Repository Pattern Implementation
app/lib/PhpMyCoder/Repository/Repository.php:
<?php namespace PhpMyCoder\Repository;
interface Repository {
public function all();
public function find($id);
}
app/lib/PhpMyCoder/Repository/Order/OrderRepository.php:
<?php namespace PhpMyCoder\Repository\Order;
interface OrderRepository extends PhpMyCoder\Repository\Repository {}
Adding Eloquent Repositories (and a hack)
app/lib/PhpMyCoder/Repository/Order/EloquentOrderRepository.php:
<?php namespace PhpMyCoder\Repository\Order;
use PhpMyCoder\Repository\EloquentBaseRepository;
class EloquentOrderRepository extends EloquentBaseRepository implements OrderRepository {
public function __construct(\Order $model) {
parent::__construct($model);
}
public function finished() {
return $this->model->finished()->get();
}
public function scopeFinished($query) {
return $query->where('finished', '=', true);
}
}
Notice how the repository contains the scope that would normally be stored in the Order model class. In the database (for this example), Order needs to have a boolean column finished. We'll cover the details of EloquentBaseRepository below.
app/lib/PhpMyCoder/Repository/EloquentBaseRepository.php:
<?php namespace PhpMyCoder\Repository;
use Illuminate\Database\Eloquent\Model;
abstract class EloquentBaseRepository implements Repository {
protected $model;
// Stores which repositories have already been booted
protected static $booted = array();
public function __construct(Model $model) {
$this->model = $model;
$this->bootIfNotBooted();
}
protected function bootIfNotBooted() {
// Boot once per repository class, because we only need to
// add the scopes to the model once
if(!isset(static::$booted[get_class($this)])) {
static::$booted[get_class($this)] = true;
$this->boot();
}
}
protected function boot() {
$modelScope = new ModelScope(); // covered below
$selfReflection = new \ReflectionObject($this);
foreach (get_class_methods($this) as $method) {
// Find all scope methods in the repository class
if (preg_match('/^scope(.+)$/', $method, $matches)) {
$scopeName = lcfirst($matches[1]);
// Get a closure for the scope method
$scopeMethod = $selfReflection->getMethod($method)->getClosure($this)->bindTo(null);
$modelScope->addScope($scopeName, $scopeMethod);
}
}
// Attach our special ModelScope to the Model class
call_user_func([get_class($this->model), 'addGlobalScope'], $modelScope);
}
public function __call($method, $arguments) {
// Handle calls to scopes on the repository similarly to
// how they are handled on Eloquent models
if(method_exists($this, 'scope' . ucfirst($method))) {
return call_user_func_array([$this->model, $method], $arguments)->get();
}
}
/* From PhpMyCoder\Repository\Order\OrderRepository (inherited from PhpMyCoder\Repository\Repository) */
public function all() {
return $this->model->all();
}
public function find($id) {
return $this->model->find($id);
}
}
Each time an instance of a repository class is instantiated for the first time, we boot the repository. This involves aggregating all "scope" methods on the repository into a ModelScope object and then applying that to the model. The ModelScope will apply our scopes to each query created by the model (as seen below).
app/lib/PhpMyCoder/Repository/ModelScope.php:
<?php namespace PhpMyCoder\Repository;
use Illuminate\Database\Eloquent\ScopeInterface;
use Illuminate\Database\Eloquent\Builder;
class ModelScope implements ScopeInterface {
protected $scopes = array(); // scopes we need to apply to each query
public function apply(Builder $builder) {
foreach($this->scopes as $name => $scope) {
// Add scope to the builder as a macro (hack-y)
// this mimics the behavior and return value of Builder::callScope()
$builder->macro($name, function() use($builder, $scope) {
$arguments = func_get_args();
array_unshift($arguments, $builder->getQuery());
return call_user_func_array($scope, $arguments) ?: $builder->getQuery();
});
}
}
public function remove(Builder $builder) {
// Removing is not really possible (no Builder::removeMacro),
// so we'll just overwrite the method with one that throws a
// BadMethodCallException
foreach($this->scopes as $name => $scope) {
$builder->macro($name, function() use($name) {
$className = get_class($this);
throw new \BadMethodCallException("Call to undefined method {$className}::{$name}()");
});
}
}
public function addScope($name, \Closure $scope) {
$this->scopes[$name] = $scope;
}
}
The ServiceProvider and Composer File
app/lib/PhpMyCoder/Repository/RepositoryServiceProvider.php:
<?php namespace PhpMyCoder\Repository;
use Illuminate\Support\ServiceProvider;
use PhpMyCoder\Repository\Order\EloquentOrderRepository;
class RepositoryServiceProvider extends ServiceProvider {
public function register() {
// Bind the repository interface to the eloquent repository class
$this->app->bind('PhpMyCoder\Repository\Order\OrderRepository', function() {
return new EloquentOrderRepository(new \Order);
});
}
}
Be sure to add this service provider to the providers array in the app.php config:
'PhpMyCoder\Repository\RepositoryServiceProvider',
And then add the app/lib to composer's autoload
"autoload": {
"psr-0": {
"PhpMyCoder\\": "app/lib"
},
/* etc... */
},
This will require a composer.phar dump-autoload.
The Models
app/models/Customer.php:
<?php
class Customer extends Eloquent {
public function orders() {
return $this->hasMany('Order');
}
}
Notice that for brevity, I've excluded writing a repository for Customer, but in a real application you should.
app/model/Order.php:
<?php
class Order extends Eloquent {
public function customer() {
return $this->belongsTo('Customer');
}
}
Notice how the scope is not longer stored in the Order model. This makes more structural sense, because the collection level (repository) should be responsible for scopes applying to all orders while Order should only be concerned with details specific to one order. For this demo to work, order must have an integer foreign key customer_id to customers.id and a boolean flag finished.
Usage in the Controller
app/controllers/OrderController.php:
<?php
// IoC will handle passing our controller the proper instance
use PhpMyCoder\Repository\Order\OrderRepository;
class OrderController extends BaseController {
protected $orderRepository;
public function __construct(OrderRepository $orderRepository) {
$this->orderRepository = $orderRepository;
}
public function test() {
$allOrders = $this->orderRepository->all();
// Our repository can handle scope calls similarly to how
// Eloquent models handle them
$finishedOrders = $this->orderRepository->finished();
// If we had made one, we would instead use a customer repository
// Notice though how the relation query also has order scopes
$finishedOrdersForCustomer = Customer::find(1)->orders()->finished();
}
}
Our repository not only contains the scopes for the child model, which is more SOLID. They also come with the ability to handle calls to the scope like a real Eloquent model would. And they add all scopes to each query created by the model so that you have access to them when retrieving related models.
Problems with this Approach
A lot of code for little functionality: arguably too much to accomplish the desired result
It's hacky: macros on Illuminate\Database\Eloquent\Builder and Illuminate\Database\Eloquent\ScopeInterface (in conjunction with Illuminate\Database\Eloquent\Model::addGlobalScope) are likely used in ways they weren't intended to be
It requires instantiation of the repository (MAJOR ISSUE): if you're within the CustomerController and you only have instantiated CustomerRepository, $this->customerRepository->find(1)->orders()->finished()->get() won't work as expected (the finished() macro/scope won't be added to each Order query unless you instantiate OrderRepository).
I'll investigate if there is a more elegant solution (which remedies the issues listed above), but this is the best solution I can find thus far.
Related Resources on the Repository Pattern
Creating flexible Controllers in Laravel 4 using Repositories
Eloquent tricks for better Repositories
I recently watched this video and wanted to change my Laravel controllers so that they had their dependencies managed with Laravel's IoC container. The video talks about creating an interface for a Model and then implementing that interface for the specific data source used.
My question is: when implementing the interface with a class that extends Eloquent and binding that class to the controller so that it is accessible from $this->model, should I also create interfaces and implementations for the Eloquent models which may be returned when calling methods such as $this->model->find($id)? Should there be different classes for the Model and the ModelRepository?
Put it another way: how do I do new Model when my model is in $this->model.
Generally, yes, people doing that pattern (the repository pattern) have an interface which have some methods defined that your app will use:
interface SomethingInterface {
public function find($id);
public function all();
public function paged($offset, $limit);
}
Then you create an implementation of this. If you're using Eloquent, then you can make an Eloquent implementation
use Illuminate\Database\Model;
class EloquentSomething {
protected $something;
public function __construct(Model $something)
{
$this->something = $something;
}
public function find($id)
{
return $this->something->find($id);
}
public function all() { ... }
public function paged($offset, $limit) { ... }
}
Then you make a service provider to put it all together, and add it into app/config/app.php.
use Something; // Eloquent Model
use Namespace\Path\To\EloquentSomething;
use Illuminate\Support\ServiceProvider;
class RepoServiceProvider extends ServiceProvider {
public function register()
{
$app = $this->app;
$app->bind('Namespace/Path/To/SomethingInterface', function()
{
return new EloquentSomething( new Something );
});
}
}
Finally, your controller can use that interface as a type hint:
use Namespace/Path/To/SomethingInterface;
class SomethingController extends BaseController {
protected $something;
public function __construct(SomethingInterface $something)
{
$this->something = $something;
}
public function home() { return $this->something->paged(0, 10); }
}
That should be it. Apologies on any errors, this isn't tested, but is something I do a lot.
Downsides:
More code :D
Upsides:
Able to switch out implementations (instead of EloquentSomething, can use ArraySomething, MongoSomething, whatever), without changing your controller code or any code that uses an implementation of your interface.
Testable - you can mock your Eloquent class and test the repository, or mock your constructor dependency and test your controller
Re-usable - you can App::make() to get the concrete EloquentSomething anywhere in your app and re-use the Something repository anywhere in your code
Repository is a good place to add additional logic, like a layer of cacheing, or even validation rules. Stock mucking about in your controllers.
Finally:, since I likely typed all that out and STILL DIDN'T ANSWER YOUR QUESTION (wtf?!), you can get a new instance of the model using $this->model. Here's an example for creating a new Something:
// Interface:
public function create(array $data);
// EloquentSomething:
public function create(array $data)
{
$something = this->something->newInstance();
// Continue on with creation logic
}
Key is this method, newInstance().
I've used $newModel = $this->model and it's worked for me.
For some models, we have soft deletion implemented using a valid boolean in MySQL.
In the class, the scopes method is defined as follows:
public function scopes() {
return array(
'valid'=>array(
'condition'=>"t.valid=1",
)
);
}
This is so that when we load a model we can call the scope to make it include only valid (not deleted) models alongside the other find criteria, or whatever it happens to be.
This isn't very DRY and I am wondering if there is an alternative way of achieving the same thing, that could perhaps be applied to an interface, the abstract Model class that all models derive from, or, if using 5.4, a trait.
Yii has a feature called Behaviors
that is similar to php 5.4 traits but works with earlier versions too.
SoftDeleteBehavior.php:
class SoftDeleteBehavior extends CActiveRecordBehavior {
public $deleteAttribute = 'valid';
public $deletedValue = 0;
public function beforeDelete($event) {
if ($this->deleteAttribute !== null) {
$this->getOwner()->{$this->deleteAttribute} = $this->deletedValue;
$this->getOwner()->update(array($this->deleteAttribute));
// prevent real deletion of record from database
$event->isValid = false;
}
}
/**
* Default scope to be applied to active record's default scope.
* ActiveRecord must call this from our own default scope.
* #return array the scope to be applied to default scope
*/
public function defaultScope() {
return array(
'condition' => $this->getOwner()->getTableAlias(false,false).'.'.$this->deleteAttribute
. ' <> '.var_export($this->deletedValue, true),
);
}
}
Then i have this class to apply deafultscope from behaviors:
ActiveRecord.php (i ofcourse have more methods in this class, downside is that you need to call parent method if you need to extend the method):
class ActiveRecord extends CActiveRecord {
public function defaultScope() {
$scope = new CDbCriteria();
foreach ($this->behaviors() as $name => $value) {
$behavior = $this->asa($name);
if ($behavior->enabled && method_exists($behavior,'defaultScope')) {
$scope->mergeWith($behavior->defaultScope());
}
}
return $scope;
}
}
And then you use it in your Models:
class MyModel extends ActiveRecord {
public function behaviors() {
return array(
'SoftDeleteBehavior' => array(
'class' => 'application.components.behaviors.SoftDeleteBehavior',
),
);
}
}
PROTIP: you can specify your own ActiveRecord class when you generate models with gii