laravel eloquent - how to select users - laravel

Question

I've got two tables:
Users table with id's
And Messages table with users's Id as "from" and offer Id's as offer_id
I want to select all users that send messages to with certain offer_id's
For example
user with id 1 send few messages:
Id from offer_id
1. 1, 5
2. 2, 5
3. 1, 5
4. 1, 3
I want to select all users that sent offer_id =5, so users of id 1 and 2
How to do it via eloquent with Message and User class?
I've got offer_id given so I can easily select messages:
$messages = Message::where('offer_id', $id);
but how to select users?
edit:
I tried this way:
in Message model:
public function fromContact()
{
return $this->hasOne(User::class, 'id', 'from');
}
and then in controller:
$contacts = $messages->fromContact;
but it gives an error
edit migration:
Schema::create('messages', function (Blueprint $table) {
$table->increments('id');
$table->integer('from')->unsigned();
$table->integer('to')->unsigned();
$table->boolean('read')->default(false);
$table->integer('offer_id')->nullable();
$table->mediumText('body')->nullable();
$table->timestamps();
});
and error:
"message": "Undefined property:
Illuminate\\Database\\Eloquent\\Builder::$fromContact",

Answer 1

You're missing some closure on your Query Builder. When you use
$messages = Message::where('offer_id', $id);
You don't have an instance of Message until you use a Closure, which are ->first(), ->get(), etc. So using
$message->fromContact;
Will result in an error stating that ->fromContact is not available on a Builder instance. To make this work, use
$messages = Message::where('offer_id', $id)->get();
foreach($messages AS $message){
$contacts = $message->fromContact;
}
Since this doesn't have much context in a loop, the code above doesn't do anyhting, but $messages->fromContact would also be an error. To get around that, use:
$message = Message::where('offer_id', $id)->first();
$contacts = $message->fromContact;
That should give you a good idea of what's going wrong and how to handle it.
Edit
When looping over multiple Message instances, push $message->fromContact to an array (or Collection) for use later:
$messages = Message::with(['fromContact'])->where('offer_id', $id)->get();
// Note: Using `::with()` prevents additional database calls when using `$message->fromContact` in a loop.
$contacts = []; // or $contacts = collect([]);
foreach($messages AS $message){
$contacts[] = $message->fromContact; // or $contacts->push($message->fromContact);
}