Laravel hasMany when parent doesn't exist - laravel

Parent.php
class Parent extends Model
{
public function children() {
return $this->hasMany('App\Child');
}
}
and I used this in my controller:
$children = Parent::find($parent_id)->children;
and it's OK when $parent_id exist. But when $parent_id` doesn't exist. it returns this error:
Trying to get property 'children' of non-object
What is the solution to prevent this error or return a false?

Solution is simple:
<?php
$children = null;
$parent = Parent::find($parent_id);
if ($parent) {
$children = $parent->children;
}
return $children; // or return false, or throw Exception - whatever you like
The above would return a HasMany relation if the parent exists, or false if it doesn't.
If you need a collection regardless - a better way would be to do it another way round, like this:
<?php
$children = Children::where('parent_id', $parent_id)->find();
return $children;

use Illuminate\Database\Eloquent\Collection;
$parent = Parent::find($parent_id)
$chilren = is_null($parent) ? Collection::make([]) : $parent->children; This is the first solution
You check if the parent is not null then use has many relation or return empty eloquent collection
or you can get children by parent id
Child::where('parent_id', $parent_id)->get()

$childData='';
$parentdata = Appuser::find($parent_id);
if(isset($parentdata)){
$childData = $parentdata->order;
}
return $childData;

Related

Laravel Mutators and Accessors

I have created mutator date function in model to convert the created_at date into human readable time using diffForHumans().
I have done the following
public function setDateAttribute($value){
return \Carbon\Carbon::parse($value)->diffForHumans();
}
It works fine but it affects in all. it is possible to apply this mutator only on the specified function of the controller rather than all function
A small logic in the mutator would do the job:-
public function setDateAttribute($value){
if ( request()->path() === "/yourURL/To/IndexMethod"){
return $this->attributes['date'] = \Carbon\Carbon::parse($value)->diffForHumans();
} else {
return $this->attributes['date'] = $value;
}
}
the idea is to check by the url.
getting request path helper
EDIT
Comparison using route name is better, as exact path can contain id/slugs.
public function setDateAttribute($value){
if ( \Route::currentRouteName() === "/yourRouteName/To/IndexMethod"){
return $this->attributes['date'] = \Carbon\Carbon::parse($value)->diffForHumans();
} else {
return $this->attributes['date'] = $value;
}
}
getting route name

Laravel and algolia, ignore array if null

I have this code:
public function toSearchableArray()
{
$data = $this->toArray();
$data['_geoloc'] = $this->_geoloc->toArray();
$data['address'] = $this->address->toArray();
return $data;
}
However sometimes $data['entities'] is null therefore throwing me an error:
[Symfony\Component\Debug\Exception\FatalThrowableError]
Call to a member function toArray() on null
Is there any way to by-pass that?
You need to check elements if they exist and not null before call methods on them, like this:
public function toSearchableArray()
{
$data = $this->toArray();
$data['_geoloc'] = !empty($this->_geoloc) ? $this->_geoloc->toArray() : null;
$data['address'] = !empty($this->address) ? $this->address->toArray() : '';
return $data;
}
Also $this->toArray(); will convert the model instance to an array with all relations. So you need to load them like: $this->load('_geoloc', 'address'); and call only $data = $this->toArray();
I assume address is a relation to another table.
toArray() will convert it, if it was loaded before
public function toSearchableArray()
{
$this->address;
$data = $this->toArray();
return $data;
}
Is _geoloc also a relation to another table?
I think you can try this:
public function toSearchableArray()
{
$data = $this->toArray();
$data['_geoloc'] = $this->_geoloc->toArray();
$data['address'] = $this->address->toArray();
print('<pre style="color:red;">');
print_r($data);
print('</pre>');
exit;
return $data;
}
Hope help for you !!!

Adding custom eloquent attribute in Laravel 5

I have a function named siblings which fetches all siblings of a user.
select siblings(id) as `siblings` from users where id = 1
I can access the function in Eloquent as
User::where('id', 1)->first([DB::raw(siblings(id) as `siblings`)]->siblings;
I want to make the siblings available via custom attribute.
I added siblings to $appends array
I also created getSiblingsAttribute method in my User model as
public function getSiblingsAttribute()
{
if (!$this->exists()) {
return [];
}
$siblings = User::where('idd', $this->id)
->first([DB::raw('siblings(id) AS `siblings`')])
->siblings;
return explode(',', $siblings);
}
But this is not working as $this->id returns null
My table schema is users(id, username,...), so clearly id is present.
Is there a way by which I can bind the siblings function while querying db and then returning something like $this->siblings from getSiblingsAttribute. If I can bind siblings(id) as siblings with query select globally as we do for scopes using global scope.
That way my code can be simply
public function getSiblingsAttribute()
{
return $this->siblings;
}
The simplest way is to create a view in your database and use that as a table:
protected $table = 'user_view';
Otherwise I need more information about your id == null problem.
If you can fix this by your own in the next step it is important that you use an other column name by selecting as in your accessor otherwise you run in an infinite loop.
public function getSiblingsAttribute()
{
if (!$this->exists()) {
return [];
}
$siblings = User::where('id', $this->id)
->first([DB::raw('siblings(id) AS `siblings_value`')])
->siblings_value;
return explode(',', $siblings);
}
EDIT
Sadly there is no simple way to archieve this.
But after a little bit tinkering I have found a (not very nice) solution.
Give it a try.
You have to add the following class and trait to your app.
app/Classes/AdditionalColumnsTrait.php (additional column trait)
namespace App\Classes;
trait AdditionalColumnsTrait {
public function newEloquentBuilder($query) {
$builder = new EloquentBuilder($query);
$builder->additionalColumns = $this->getAdditionalColumns();
return $builder;
}
protected function getAdditionalColumns() {
return [];
}
}
app/Classes/EloquentBuilder.php (extended EloquentBuilder)
namespace App\Classes;
use Illuminate\Database\Eloquent\Builder;
class EloquentBuilder extends Builder {
public $additionalColumns = [];
public function getModels($columns = ['*']) {
$oldColumns = is_null($this->query->columns) ? [] : $this->query->columns;
$withTablePrefix = $this->getModel()->getTable() . '.*';
if (in_array('*', $columns) && !in_array($withTablePrefix, $oldColumns)) {
$this->query->addSelect(array_merge($columns, array_values($this->additionalColumns)));
} elseif (in_array($withTablePrefix, $oldColumns)) {
$this->query->addSelect(array_values($this->additionalColumns));
} else {
foreach ($this->additionalColumns as $name => $additionalColumn) {
if (!is_string($name)) {
$name = $additionalColumn;
}
if (in_array($name, $columns)) {
if (($key = array_search($name, $columns)) !== false) {
unset($columns[$key]);
}
$this->query->addSelect($additionalColumn);
}
}
if (is_null($oldColumns)) {
$this->query->addSelect($columns);
}
}
return parent::getModels($columns);
}
}
after that you can edit your model like this:
class User extends Model {
...
use App\Classes\AdditionalColumnsTrait;
protected function getAdditionalColumns() {
return [
'siblings' => DB::raw(siblings(id) as siblings)),
];
}
...
}
now your siblings column will be selected by default.
Also you have the option to select only specific columns.
If you don't want to select the additional columns you can use: User::find(['users.*']).
Perhaps it is a solution for you.

Retrieve parent class within morph relationship

I have this code
//ImageableTrait
trait ImageableTrait
{
public function images()
{
return $this->morphMany(Image::class, 'imageable')
->orderBy('order', 'ASC');
}
}
//User
class User extend Model
{
use ImageableTrait;
}
//Post
class Post extend Model
{
use ImageableTrait;
}
class ImageCollection extends Collection
{
public function firstOrDefault()
{
if ($this->count() === 0) {
$image = new Image();
$image->id = 'default';
$image->imageable_type = '/* I need the parent className here */';
$image->imageable_id = '.';
}
return $this->first();
}
}
//Image
class Image extend Model
{
public function imageable
{
return $this->morphTo();
}
public function newCollection(array $models = [])
{
return new ImageCollection($models);
}
public function path($size)
{
//Here, there is some logic to build the image path and it needs
//the imageable_type attribute no matter if there is
//an image record in the database or not
return;
}
}
I want to be able to do so
$path = User::find($id)->images->firstOrDefault()->path('large');
But I can't figure out how to get the parent class name to build the path properly...
I tried with $morphClass or getMorphClass() but can't figure out how to use it properly or if it is even the right way to do it.
Any thoughts on that?
I think you can keep it simple and drop the ImageCollection class because there is already a firstOrNew method that seems to be what you're looking for.
The firstOrNew method accepts an array of attributes that you want to match. If you don't care about the attributes, you can pass an empty array. If there are no matches in the database, it'll make a new instance with the proper parent type.
$path = User::find($id)->images()->firstOrNew([])->path('large');
Note: I am calling the images() method to get the MorphMany object so that I can call the firstOrNew method. In other words, you need to add the parentheses. Otherwise, you get a Collection.
Edit: If you want to make things a bit simpler by automatically setting some default attributes, you can add this to your ImageableTrait:
public function imagesOrDefault()
{
$defaultAttributes = ['id' => 'default'];
return $this->images()->firstOrNew($defaultAttributes);
}
Then, you can do something like this: $path = User::find($id)->imagesOrDefault()->path('large');
Note that your default attributes must be fillable for this to work. Also, imageable_id and imageable_type will automatically be set to your parent's id and type.
If you want to set the default value for imageable_id to a period and not the parent's id, then you have to alter it a bit, and it will look a lot like your original code except this will go inside your ImageableTrait.
public function imagesOrDefault()
{
// First only gets one image.
// If you want to get all images, then change it to get.
// But if you do that, change the conditional check to a count.
$image = $this->images()->first();
if (is_null($image))
{
$image = new Image();
$image->id = 'default';
$image->imageable_type = $this->getMorphClass();
$image->imageable_id = '.';
}
return $image;
}
Ok guys I've found something that seems to work pretty good for now so I'll stick with that.
In the Image model, I've added some code when I make the new collection:
public function newCollection(array $models = [])
{
$morphClass = '';
$parent = debug_backtrace(false, 2)[1];
if (isset($parent['function']) AND $parent['function'] === 'initRelation') {
if (isset($parent['args'][0][0])) {
$morphClass = get_class($parent['args'][0][0]);
}
}
return new ImageCollection($models, $morphClass);
}
I then simply retrieve the morphClass through the constructor of the ImageCollection
private $morphClass;
public function __construct($items = [], $morphClass)
{
parent::__construct($items);
$this->morphClass = $morphClass;
}
public function firstOrDefault()
{
if ($this->count() === 0) {
$image = new Image();
$image->id = 'default';
$image->imageable_type = $this->morphClass;
$image->imageable_id = '.';
}
return $this->first();
}
This way, I can simply call the method like that
User::with('images')->get()->images->firstOrDefault()
This seems to work really great in many cases, if I have some issues at some times, I'll update this post.
i may be late for the party, but i kinda did a small trick for morph relationships where i had "media" as morph, i get the parent since "model_type" has the full string parent class string.
$model = new $media->model_type;
$media->model = $model->findOrFail($media->model_id);

Laravel 4 hasMany with WHERE clause

Not sure if this is the correct way to add an additional query to the hasMany argument but was unsuccessful. Is this possible?
public function menuItems($parent=false){
if($parent){
$menuItems = $this->hasMany('MenuItem')->where('parent',$parent);
}else{
$menuItems = $this->hasMany('MenuItem');
}
return $menuItems;
}
When called using
$menu_items = $menu->menuItems(0);
This just seems to return an empty array when passed a parent. Even though data with MenuItem->parent = 0 exists
Do I need to some way distinguish I'm asking for my linked items "parent" and not the main models "parent"
public function menuItems(){
return $this->hasMany('MenuItem');
}
Called with
$menu_items = $menu->menuItems()->where('parent', 0)->get();
I am not sure about the query part but at first wouldn't passing a 0 to the function still register the $parent variable as false? So maybe just check if the $parent is not null.
public function menuItems($parent = null){
if(!$parent == null)){
$menuItems = $this->hasMany('MenuItem')->where('parent',$parent);
}else{
$menuItems = $this->hasMany('MenuItem');
}
return $menuItems;
}
In PHP 0 = FALSE, change this
if( $parent ){
for this
if( $parent !== false ){

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