How to validate pivot table in Laravel? - php

Question

In the admin panel, I have something called Group that an admin can make a group of users so my scheme is:
groups table contains:
id
name
1
group1
group_user table contains:
id
group_id
user_id
1
1
2
2
1
3
My logic is: if a user belongs to a group, that user cannot be added again to the same group:
In update, when I add a user that already exists in group, it added it again:
public function update($id, Request $request)
{
$request->validate([
'name' => 'sometimes|nullable|string',
'user_ids' => 'sometimes|array',
]);
$group = Group::findOrFail($id);
$group->update($request->only('name'));
if ($ids = $request->user_ids) {
$group->users()->attach($ids);
}
return $this->apiRespone(null, 'group updated successfully', null, 200);
}

Answer 1

Just check if user already is in the group before attaching to it:
public function update($id, Request $request)
{
$request->validate([
'name' => 'sometimes|nullable|string',
'user_ids' => 'sometimes|array',
]);
$group = Group::findOrFail($id);
$group->update($request->only('name'));
foreach($request->user_ids as $user_id) {
if (!$group->users()->where('id', $user_id)->exists()) {
$group->users()->attach($user_id);
}
}
return $this->apiRespone(null, 'group updated successfully', null, 200);
}
Update:
To get the list of already existing members, apply this in your loop logic:
$existingUsers = [];
foreach($request->user_ids as $user_id) {
if (!$group->users()->where('id', $user_id)->exists()) {
$group->users()->attach($user_id);
} else {
$existingUsers[] = $user_id;
}
}
// now you can use $existingUsers