Trying to delete only one row in table - Laravel - laravel-5.4

Question

I am trying to update some users info. Here is my code :
public function update(Request $request, $id)
{
$user = Auth::user();
$user_id = Auth::user()->id;
$arrRequest = $request->all();
$contact = Contact::findOrFail($id)->where('user_id', $user_id);
$validator = Validator::make($arrRequest, Contact::$rules);
$content = null;
if ($validator->fails()) {
$status = 400;
$content = $validator->errors();
} else {
$contact->update($arrRequest)->save();
$status = 200;
}
return response($content, $status);
}
The main problem is that the request is applied to all rows in the table though I'm specifying the $id of the row for the request to be applied to. I'm struggling to see where is my mistake. The second problem (that just popped up) is that when I perform the request I'm now getting a message that says : Call to a member function save() on integer. But it was working just fine earlier (except it was updating all rows..) ! And Im retrieving an object ($contact) and not just an integer...
Thanks !

Answer 1

You are using findOrFail() method, which returns a Model or Collection.
After that you actually convert $contact into a Builder object by appending the where() method on the findOrFail() result. findOrFail() expects either an $id or array of $ids and will return a Model or Collection, not a Builder.
If you just want to make sure that the requested id is owned by the user, you can either check that after fetching the object, or use something other than findOrFail().
$contact = Contact::findOrFail($id);
if ($contact->user_id != $user->id) {
abort(403);
}
or
$contact = Contact::where('id', $id)
->where('user_id', $user->id)
->first();
if (! $contact) {
abort(404);
}
Although I would not recommend the last one, just the $id should be enough to fetch the item you want.
The second error is caused by calling save() after update(), update() will return a boolean.

Answer 2

I've finally managed to make it work.. some weirds things happening though.
Here is my solution :
public function update(Request $request, $id)
{
$user = Auth::user();
$user_id = Auth::user()->id;
$arrRequest = $request->all();
$contact = Contact::where('user_id', $user_id)->find($id);
$validator = Validator::make($arrRequest, Contact::$rules);
$content = null;
if ($validator->fails()) {
$status = 400;
$content = $validator->errors();
} else {
$contact->update($arrRequest);
$contact->save();
$status = 201;
}
return response($content, $status);
}
Thanks to Robert I can understand some parts of it. I guess if I make update() first then save() (not in a row), my save method is applying to the object and not the returned boolean? and thats why it works? still learning ahah !