I am trying to create relation between two tables, users and messages in Laravel models, as the user can send a message to another user so that I have two foreign-keys (fromUser_id and toUser_id) as shown in the image below.
For the first relation it is straightforward that I will create a function with the name messages
public function messages(){
return $this->hasMany('App\Models\Message', 'fromUser_id');
}
However I do not know how to name the second relation as far as I know it should be messages too, according to the standard naming of Laravel, which will obviously issue an error as we have the first function with the same name.
public function messages(){
return $this->hasMany('App\Models\Message', 'toUser_id');
}
Would you please let me know what should I name it and how this will affect the models.
Well, you should not use simple messages as relationship but rather use receivedMessages and sentMessages like this:
public function sentMessages()
{
return $this->hasMany('App\Models\Message', 'fromUser_id');
}
public function receivedMessages()
{
return $this->hasMany('App\Models\Message', 'toUser_id');
}
Related
I am trying to make a function that will help me get needed data quickly.
With all the trials I have been able to get to the following
Tables:
Users (id,name)
Projects (id,name)
User-Project (id, user_id, project_id, manager) where manager is a boolean , there can only be one manager for each project (but employees can still see the project reason why we have a pivot table, manager = 0 for other normal users that can access that project)
In the Project Model I have:
public function Manager(){
return $this->belongsToMany('App\User')->wherePivot('manager', true);
}
In the View I have:
<p><strong>Project Manager:</strong> {{$project->manager}}</p>
On the actual page I get:
Project Manager: [{"id":4,"name":"Daniel Doe","email":"danieldoe#hotmail.com","phone":"70846556","email_verified_at":null,"created_at":"2020-12-20 21:05:50","updated_at":"2020-12-20 21:05:50","pivot":{"project_id":1,"user_id":4,"manager":1}}]
When I change the view to:
<p><strong>Project Manager:</strong> {{$project->manager[0]->name}}</p>
I get:
Project Manager: Daniel Doe
This is what I actually want but I would like to do it from the model if possible. So I tried:
public function Manager(){
return $this->belongsToMany('App\User')->wherePivot('manager', true)->first()->name;
}
But I get the following error:
must return a relationship instance
Can this be done from the model's function?
You can keep your defined relationship, but to access ->first()->name, you'll need to use an "Accessor":
public function manager() {
return $this->belongsToMany('App\User')->wherePivot('manager', true);
}
public function getManagerNameAttribute() {
return $this->manager->first() ? $this->manager->first()->name : 'No Manager';
}
Then, in your code, you simple access:
{{ $project->manager_name }}
If your manager() function returns a Collection of at least 1 record, it will return the name, otherwise it will display 'No Manager' as a fallback.
If you don't want to change the structure of this you can use an accessor to get this information, roughly something like this:
class Project ...
{
public function users()
{
return $this->belongsToMany(...)->withPivot(...);
}
public function getManagerAttribute()
{
return $this->users()->wherePivot('manager', 1)->first()?->name;
}
}
You can do this in different ways, you could use the loaded users relation and use a the Collection methods to filter the manager. You could create another relationship called managers that uses the wherePivot off of users(), etc ...
The only thing to worry about with this setup is that every call to $model->manager would be causing that query, so it may be a good idea to create another relationship manager so that you can load that once and keep using it without the need to keep querying the database:
public function managers()
{
return $this->users()->wherePivot(...);
}
public function getManagerAttribute()
{
return $this->managers->first()?->name;
}
Though, as mentioned already it is probably better to have something like a manager_id on the Project itself.
I'm trying to create a function in our Laravel 5.8 app that would add multiple records to a pivot table. At present we have the following setup;
Users
Training Courses
Users Training Courses (pivot table for the above relationships, with a few extra fields)
I want to be able to show all users in the database, then check their name, pick a training course and hit "Add" and it'll create a record in the pivot table for each user that was selected.
I can't figure out where to start with this - it seems like I need to have a "for each user selected, run the store function" loop in the controller, but I have no idea where to start.
I wasn't sure if there was an easy way to do this in eloquent or not. Is there a simple way to do this?
Eloquent does this automatically if you set up the relationships correctly and you don't have to worry about pivot tables.
class Users
{
public function trainingCourses()
{
return $this->hasMany(TrainingCourses::class);
}
}
class TrainingCourses
{
public function user()
{
return $this->belongsTo(User::class);
}
}
Then you can use the save() method to create the relationship. But I find it better to wrap this function inside a helper method that you can use throughout your code:
class Users
{
...
public function assignTrainingCourse(TrainingCourse $trainingCourse)
{
return $this->trainingCourses()->save($trainingCourse);
}
}
In your code, you could then do something as simple as this:
$user = User::find(1);
$trainingCourse = TrainingCourse::find(1);
$user->assignTrainingCourse($trainingCourse);
Building on this, suppose you have the following route to assign a training course, where it expects a trainingcourse_id in the request:
Route::post('/users/{user}/trainingcourses', 'UserTrainingCoursesController#store');
Thanks to route model binding, Laravel can inference the parent model (user) from the URL, and your controller might look like this:
// UserTrainingCoursesController.php
public function store(User $user)
{
$trainingCourse = TrainingCourse::find(request()->input('trainingcourse_id'));
$user->assignTrainingCourse($trainingCourse);
return back();
}
Of course, you'll want to put some validation in here, but this should get you started.
I have two models Customer, Contact with the following relationship in the Customer model:
public function latestContact () {
return $this->hasOne(Contact::class)->latest();
}
I already found out here that the optional helper is a possible to way check if the relationship exists when displaying the data. Otherwise I would receive a "Trying to get property of non-object" error.
optional($customer->latestContact)->address
Now I am wondering if there is a way to directly check this inside the model function. I would prefer to only call
$customer->latestContact->address
or something like
$customer->getLatestContactAdress
and return false (or no result) if the relationship does not exists.
Thank you in advance.
You could define an accessor or a function within your parent model.
Something like this in your Customer model:
public function getLatestContactAddress()
{
return optional($this->latestContact)->address;
}
And call it like this:
$customer->getLatestContactAddress();
Try using eager loading
$customer = Customer::with('latestContact')->get();
Let me know if not works
I have 3 databases:
Routes:
id
name
Rates:
Id
Route_id
Car_id
Cars:
id
name
My model for routes
public function rates()
{
return $this->hasMany('App\Rate', 'route_id');
}
My model for rates
public function car() {
return $this->belongsTo('App\Car','car_id');
}
Now I need to access the car relation, but when I do
return $this->route->with('from','to','rates.car')->paginate(74);
I get null for the car relation
{"id":1,"from_id":1,"to_id":2,"distance":400,"created_at":null,"updated_at":null,"from":{"id":1,"name":"\u0410\u043a\u043a\u043e","created_at":null,"updated_at":null,"lat":32.93310000000000314912540488876402378082275390625,"long":35.0827000000000026602720026858150959014892578125},"to":{"id":2,"name":"\u0410\u0440\u0430\u0434","created_at":null,"updated_at":null,"lat":31.261399999999998300381776061840355396270751953125,"long":35.21490000000000009094947017729282379150390625},"rates":[{"id":1,"route_id":1,"car_id":1,"rate":1123,"night_rate":1391,"car":null},{"id":5551,"route_id":1,"car_id":2,"rate":1123,"night_rate":1391,"car":null},{"id":11101,"route_id":1,"car_id":3,"rate":1123,"night_rate":1391,"car":null},{"id":16651,"route_id":1,"car_id":4,"rate":1123,"night_rate":1391,"car":null},{"id":22201,"route_id":1,"car_id":5,"rate":1123,"night_rate":1391,"car":null},{"id":27751,"route_id":1,"car_id":6,"rate":1123,"night_rate":1391,"car":null},{"id":33301,"route_id":1,"car_id":7,"rate":1123,"night_rate":1391,"car":null},{"id":38851,"route_id":1,"car_id":8,"rate":1123,"night_rate":1391,"car":null}]},
From my understanding you are trying to access a Car model through a Route model.
A couple of things I noticed that should help you find a solution.
First off I think the inverse relation you are supposed to use the belongToMany() function instead.
public function car() {
return $this->belongsToMany('App\Car','Rates'); // Perhaps call the table something like routes_cars to more clearly define it's a pivot table
}
Next I see you are trying to use model functions within the context of $this(). I assume you are doing this in your model? That logic should be in a controller, that might cause some undesired results but I'm not entirely sure. Also it looks like your parameters are incorrect when using with(). You use the function name that you defined in belongsToMany()
App/Route::with('car')->paginate(74);
With the correct relationships setup you rarely need to worry about the pivot table. If you are going to add extra information in the pivot table there are laravel functions to help you do that in the documentation.
I have three tables - "courses", "lessons" and "tasks". Each lesson belongsTo a course, and each task BelongsTo a lesson. I want to output a task, showing the task name, the lesson name, and the course name. How do I access the course table data? To get the lesson information linked to a course, I have used the following in my Task model:
$lessonName = $this->lessons->lesson_name;
To get the course name associated to that lesson, I have tried the following with no success, but I am really guessing here:
$courseName = $this->lessons->courses->course_name;
My model relationships are as follows:
Course.php
public function lessons()
{
return $this->hasMany('App\Lesson');
}
Lesson.php
public function tasks()
{
return $this->belongsTo('App\Task', 'task_id', 'id');
}
Task.php
public function lessons()
{
return $this->belongsTo('App\Lesson', 'lesson_id', 'id');
}
Where am I going wrong? Thanks
there is another way you can do this by using accessors.
on your Task model do the following:
public function getLessonAttribute(){
return Lesson::where('id', $this->attributes[*foreign_key_field*])->first();
}
Here you receive all the data regarding the lesson that the task belongs to, and can use them as any other attribute (field) of the model.
on your Lesson model get the course that it belongs to.
public function getCourseAttribute(){
return Course::where('id', $this->attributes[*course_foreign_key_field*])->first();
}
and then assuming that $task is your collection, you can access the lesson and the course like the following in blade:
$task->lesson->lesson_name and $task->lesson->course->course_name
In your lesson.php model doesn't exist relationship courses so there are your issue. Use answer what is told you #jeroenF
So you want the inverse of hasManyThrough?
The hasManyThrough feature of Laravel (see their site) facilitates connecting your Courses to Task directly, without having the intermediate connection in a separate relationship.
You are looking for the inverse?