Updating/Adding value to array in Laravel 8 - php

Question

I am new developer, and I seem to be stuck on handling arrays in laravel. I am using Laravel 8, and I cant seem to solve this situation.
I am building an internal recruitment site, where once a manager posts a job, employees will be able to apply to those specific jobs. I have defined the table in the database to have the "applicants" as an array consisting of the user_id's. However, I seem to not be able to add more than one array to it.
Below is my Recruitment Model
class Recruitment extends Model
{
use HasFactory;
protected $fillable = [
'title',
'salary',
'term_start',
'term_end',
'deadline',
'details',
'status',
'applicants',
];
public function user(){
return $this->belongsTo("\App\Models\User");
}
protected $casts = [
'applicants' => 'array'
];
}
Next is my migration (I am using text format, because the DB on the server is older and does not support json)
public function up()
{
Schema::create('recruitments', function (Blueprint $table) {
$table->id();
$table->string('title');
$table->decimal('salary', 10, 2);
$table->date('term_start');
$table->date('term_end');
$table->date('deadline');
$table->longText('details');
$table->string('status');
$table->text('applicants')->nullable();
$table->timestamps();
});
}
Here is my blade
<div class="container">
<div class="row">
<div class="card col-sm-12 py-3">
<div class="card-header border d-flex justify-content-between align-items-center">
<h3 class="w-75">{{ $job->title }}</h3>
<div class="w-25">
<p class="my-0 my-0">Created at: <span class="text-info">{{ $job->created_at }}</span></p>
<p class="my-0 my-0">Last updated at: <span class="text-primary">{{ $job->updated_at }}</span></p>
</div>
</div>
<div class="card-body">
// display job details here
<form action="{{ route('add-applicant', ['id' => $job->id ]) }}" method="POST" class="col-sm-12 d-flex justify-content-center align-items-center">
#csrf
<input type="text" name="user_id" id="user_id" value="{{ Auth::user()->id }}" hidden>
<button type="submit" class="btn btn-success w-25">Apply</button>
</form>
</div>
</div>
</div>
</div>
and lastly my controller
public function addApplicant($id, Request $reqst){
$job = Recruitment::find($id);
$user[] = $reqst->user_id;
$job->applicants = $user;
$job->save();
return redirect()->back();
}
While this controller will be able to save an array, it unfortunately overwrites the already existing one (let's say a second user applied). When I try to use an array_push, it does nothing, and I still end up with just one value in the array.
Sorry this was a bit of a read, but I appreciate any help I cen get with this. Thanks

Answer 1

Try in
public function addApplicant($id, Request $reqst){
$job = Recruitment::find($id);
$job->applicants = $reqst->user_id;
$job->save();
return redirect()->back();
}
and in Recruitment model should have
public function user()
{
return $this->belongsTo(User::class, 'applicants');
}
and migration file
$table->integer('applicants')->nullable();