I have a polymorphic relationship with Laravel.
My polymorphic relationship is Message->messageable becoming either Group or Chat.
Going from Message->messageable will give me the proper result(e.g the group or chat the message is associated with).
Going from example Group::first()->with('messages')->get() will return an empty messages array.
My db tables for message are
messageable_id
messageable_type
My model methods are as follows
class Message extends Model
{
public function messageable(){
return $this->morphTo();
}
^works as intended
class Group extends Model
{
function messages(){
return $this->morphMany('Message','messageable');
}
class Chat extends Model
{
public function messages(){
return $this->morphMany('Message','messageable');
These return empty.
example data used:
1
Any ideas?
You relationships are incorrect. You need to reference the full class namespace, not just the class name itself. E.g.
class Group extends Model
{
public function messages()
{
return $this->morphMany(\App\Models\Message::class', 'messageable');
}
}
Forgot to include namespaces in my Database messageable_type.
Changed from Group to App\Group.
Related
I want to have two tables one for Employees and one for Companies, both Employees & Companies should be registered within the site, thus they should have records in the users table provided with Laravel. How should I structure the relationships between the models, should I go for polymorphic relationships or use one to one?
The answer is to add two columns to the "users" table: userable_id and userable_type. userable_id will be used to store the id of the row for the entity (Employee or Company), and the userable_type will hold the class path for the Eloquent model.
in create_users_table migration file add these two lines:
// ...
$table->integer('userable_id')->unsigned();
$table->string('userable_type');
// ...
in User.php model:
class User extends Model {
// Add this declaration.
public function userable()
{
return $this->morphTo();
}
}
in your Company.php model:
class Company extends Model
{
// Add this method.
public function user()
{
return $this->morphMany(User::class, 'userable');
}
}
in the Employee.php model do the same as above:
class Employee extends Model
{
// Add this method.
public function user()
{
return $this->morphMany(User::class, 'userable');
}
}
Now you should be able to access the user by running:
App\Company::all()->get(1)->user;
// or
App\Employee::all()->get(1)->user;
And access the entity with this one-liner:
App\User::all()->get(1)->userable;
I had an accessor set on my Eloquent model that worked fine, but the associated database query was getting run once for every instance of the model I created. On my index page this meant 5 dozen queries.
<?php
class Thingy extends Model {
protected $appends = ["parentType"];
public function getParentTypeAttribute($value) {
return self::where("type"=>$this->type, "parent"=>1)->value("name");
}
}
class ThingyController extends Controller {
public function index() {
$thingys = Thingy::all();
return view("things.index", compact("thingys"));
}
}
To explain briefly: there are two classes of "thingy" in the same database table, the class being indicated by a boolean value named "parent." I want to get the name of the parent when I access the child. I know this should be two tables but it's not.
I wanted to reduce the number of database reads, so I tried changing it to a relationship instead. I figured this way I could take advantage of eager loading.
<?php
class Thingy extends Model {
public function parent() {
return $this->hasOne("Thingy", "id")->where("type"=>$this->type, "parent"=>1);
}
}
class ThingyController extends Controller {
public function index() {
$thingys = Thingy::with(["parent"]);
return view("things.index", compact("thingys"));
}
}
The problem is that within the relationship method, $this is an empty instance of the model, unlike in the accessor, so $this->type is null.
Is there a way to access properties of the model I'm working with from within a relationship method?
Figured that out. Since I'm essentially doing a self-join on the same table, I can specify the "local" and "foreign" ID columns as the column I'm trying to match:
public function parent() {
return $this->hasOne("Thingy", "type", "type")->where("parent"=>1);
}
I guess the key concept was to remember that I'm defining a relationship between two instances of the model, which is independent of the particular instances I'm dealing with.
I have a model Page and many models called SomethingSection - they're connected through a polymorphic m-m realtionship and the pivot has an additional column 'position'.
I need to write a relationship (or accessor maybe?) on the Page model that will return a collection of all connected Sections, regardless of their model (read: table).
My models:
class Page extends Model {
public function introSections()
{
return $this->morphedByMany(IntroSection::class, 'pagable');
}
public function anotherSections()
{
return $this->morphedByMany(AnotherSection::class, 'pagable');
}
}
class IntroSection extends Model {
public function pages()
{
return $this->morphToMany(Page::class, 'pagable');
}
}
class AnotherSection extends Model {
public function pages()
{
return $this->morphToMany(Page::class, 'pagable');
}
}
The pivot column looks like this:
pagables
-page_id
-pagable_id
-pagable_type
-position
I'm looking for a way to call a method/attribute on the Page model and get all the connected sections in a single collection, sorted too. What would be a good way to go about this?
I understand that the connected sections do not have the same interface, but in my case that's not a problem at all (in terms of what I will do with the data).
I also understand that relationships perform a separate query (for each relationship), so getting all of them with 1 query is impossible (also different interfaces would be a problem here). And for the same reason the sorting will need to be done on the collection level, not in query.
How could I make this as maintainable as possible and preferably with as small a performance hit as possible.
Thanks in advance.
You can use withPivot() method after your relationship to get the pivot columns with relation like this:
class Page extends Model {
public function introSections()
{
return $this->morphedByMany(\HIT\Models\Sections\IntroSection::class, 'pagable')
->withPivot(['position']);
}
public function anotherSections()
{
return $this->morphedByMany(AnotherSection::class, 'pagable');
}
}
class IntroSection extends Model {
public function pages()
{
return $this->morphToMany(Page::class, 'pagable')
->withPivot(['position']);
}
}
and you can use collection's sortBy to sort the collection by using sortBy() method like this:
$sorted_collection = IntroSection::pages->sortBy('pagables.position');
UPDATE:
You can use collection's combine() method to get all the relationships like this, add this method inside your Page Class:
public function getAllSections()
{
return $this->introSections->combine($this->anotherSections-toArray())
->sortBy('pagables.position'):
}
Hope this helps!
I'm trying to understand polymorphic relationship in Laravel. I know how it works in principle, but the choice of wording in Laravel is not intuitive in this part. Given the exanple,
namespace App;
use Illuminate\Database\Eloquent\Model;
class Like extends Model
{
/**
* Get all of the owning likeable models.
*/
public function likeable()
{
return $this->morphTo();
}
}
class Post extends Model
{
/**
* Get all of the product's likes.
*/
public function likes()
{
return $this->morphMany('App\Like', 'likeable');
}
}
class Comment extends Model
{
/**
* Get all of the comment's likes.
*/
public function likes()
{
return $this->morphMany('App\Like', 'likeable');
}
}
How do yo put in plain English sentence morphTo for instance? It is "belongsto"? and morphmany, hasMany? going further,
$post = App\Post::find(1);
foreach ($post->likes as $like) {
//
}
$likeable = $like->likeable;
morphToMany and morphByMany
How do you describe in plain english?
A polymorphic relationship means an object can have a relationship to more than one type of object. This is determined by two fields in the database rather the typical one foreign key field you would normally see.
Using the code you included in your question any type of object extending the Model class can have a relationship with a Like object. So you could have Comments and Posts that can have Likes associated to them. In your likes table you may have rows where 'likable_type' = 'post' and 'likable_id' = 1 or 'likable_type' = 'comment' and 'likable_id' = 4 for example.
The application has the models:
Atividade.php
class Atividade extends Eloquent {
public function intervencoes() {
return $this->belongsToMany('Intervencao');
}
}
Intervencao.php
class Intervencao extends Eloquent {
public function atividades() {
return $this->hasMany('Atividade');
}
}
The following code works:
Atividade::find($id)->intervencoes()->attach($intervencao_id);
But, this...
Intervencao::find($id)->atividades()->attach($atividade_id);
Returns an BadMethodCallException:
Call to undefined method Illuminate\Database\Query\Builder::attach()
SOLUTION (thanks to #gnack):
I was trying to set a many-to-many relationship, so just needed to change this...
return $this->hasMany('Atividade');
To this:
return $this->belongsToMany('Atividade');
See the Laravel documentation here:
http://laravel.com/docs/eloquent#inserting-related-models
Basically you have set up two different types of relationships for the same two tables - you've set up a many-to-many and a one-to-many. It looks as though you probably wanted a many-to-many, so you'll need to change this line:
return $this->hasMany('Atividade');
To this:
return $this->belongsToMany('Atividade');
This will set the relationship up as a many-to-many relationship, which will then support the attach() method.
The attach() method is only for many-to-many, for other relationships there's save() or saveMany() and associate() (see the docs linked above).
See the documentation Laravel 5.7
A Comment belongTo an unique Post
class Comment extends Model
{
/**
* Get the post that owns the comment.
*/
public function post()
{
return $this->belongsTo('App\Post');
}
}
A Post can Have multiple Comments
class Post extends Model
{
/**
* Get the comments for the blog post.
*/
public function comments()
{
return $this->hasMany('App\Comment');
}
When you want to update/delete a belongsTo relationship, you may use the associate/dissociate method.
$post= App\Post::find(10);
$comment= App\Comment::find(3);
$comment->post()->associate($post); //update the model
$comment->save(); //you have to call save() method
//delete operation
$comment->post()->dissociate();
$comment->save(); //save() method
attach() is for many-to-many relationships. It seems your relationship is supposed to be a many-to-many but you have not set it up correctly for that.
class Intervencao extends Eloquent {
public function atividades() {
return $this->belongsToMany('Atividade');
}
}
Then the attach() should work
In my case I've two roles() methods that's why it's throwing this error.