How can I unscope a model on create in laravel - laravel

Question

I have a Has and Belongs To Many relationship between leads and statuses. A Lead is a prospective customer. The statuses can be active, on hold, unsubscribed, etc. I have the following tables:
| Leads | Lead_Status | Statuses |
|---------|--------------|----------|
| - id | - lead_id | - id |
| - name | - status_id | - name |
We have multiple statuses for each lead because we need to keep track of the status history for analytics. This is all working great. It is common to apply a global scope as opposed to query scope to a model if the scope is used in most of the queries. My scope does something ugly to retrieve the current status of the lead and make it easily accessible with something like $lead->status that same way we get $lead->name. Here is the scoping process using newQuery to add query info to the initial query when getting the Lead:::
public function newQuery() {
return parent::newQuery()->select(DB::raw('leads.*, status.status_id AS status'))->from(DB::raw(' leads
LEFT OUTER JOIN (
SELECT ls.status_id, ls.lead_id
FROM (
SELECT lead_id, max(created_at) AS max_created_at
FROM lead_status GROUP BY lead_id
) AS ls2 INNER JOIN lead_status AS ls ON ls.lead_id = ls2.lead_id AND ls.created_at = ls2.max_created_at
) AS status ON leads.id = status.lead_id
'));
}
This works really well. It returns the lead with id, name and status.
Now for the problem:
When I try to create a new Lead I get an error:
SQLSTATE[42000]: Syntax error or access violation: 1064 You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near
'
LEFT OUTER JOIN (
SELECT ls.status_id, ls.lead_id
FROM (
' at line 2
(SQL:
insert into leads
LEFT OUTER JOIN (
SELECT ls.status_id, ls.lead_id
FROM (
SELECT lead_id, max(created_at) AS max_created_at
FROM lead_status GROUP BY lead_id
) AS ls2
INNER JOIN lead_status AS ls ON ls.lead_id = ls2.lead_id
AND ls.created_at = ls2.max_created_at
) AS status ON leads.id = status.lead_id
(`id`, `name`, `updated_at`, `created_at`) values (test5, Dustin Griffith, 2014-12-03 18:24:06, 2014-12-03 18:24:06)
)
It is obvious that the Lead is being scoped on Lead::create(). This is not what I want. I want it to scope only when we are selecting data from the leads table. So my main question is how do I tell this to only scope when it is a select statement?
I have also used the ScopeInterface method seen in the laravel docs under global scope which is more complex but favored in some situations. I can add that if we should be building off of that instead of the older newQuery method. I had the same results with that method.
I am not looking for a hacky solution. Any input will be greatly appreciated but I am searching for the correct way to handle these situations because I will be doing this time and time again in the future.

Answer 1

newQuery isn't the right method for this. What we want to use is Global Scope method mentioned in the question. This allows us to define the scoping used every time the query is called as well as how to remove the scoping when it isn't needed. Laravel is smart enough to remove the scoping when needed (create, update, delete). The Docs read:
If an Eloquent model uses a trait that has a method matching the bootNameOfTrait naming convention, that trait method will be called when the Eloquent model is booted, giving you an opportunity to register a global scope, or do anything else you want. A scope must implement ScopeInterface, which specifies two methods: apply and remove.
I skipped the trait part and placed the following in the model itself but for organization it would be wise to break this into its own Trait. I added the following to the model:
// Import the classes
use Illuminate\Database\Eloquent\Builder;
use Illuminate\Database\Eloquent\ScopeInterface;
// Add the global scope
public static function boot() {
parent::boot();
static::addGlobalScope(new StatusColumnScope);
}
// Create the scope
class StatusColumnScope implements ScopeInterface {
// Create our apply method that will be called for every query on this model
public function apply(Builder $builder) {
$builder->select(DB::raw('leads.*, status.status_id AS status'))->from(DB::raw(' leads
LEFT OUTER JOIN (
SELECT ls.status_id, ls.lead_id
FROM (
SELECT lead_id, max(created_at) AS max_created_at
FROM lead_status GROUP BY lead_id
) AS ls2 INNER JOIN lead_status AS ls ON ls.lead_id = ls2.lead_id AND ls.created_at = ls2.max_created_at
) AS status ON leads.id = status.lead_id
'));
}
// Create the remove method that is called every time we need to unscope
public function remove(Builder $builder) {
$query = $builder->getQuery();
$query->selectRaw('select *')->from('leads');
}
}
The remove method above is called when we need to un-scope. This was confusing to me at first because I was thinking it should just not scope if we don't need to scope. This isn't how Laravel works though. This only became appearant after really digging in. I will show you what I saw. Let's look under the hood of Laravel at a few methods in Eloquent/Builder.php:
create:
public static function create(array $attributes) {
$model = new static($attributes);
$model->save();
return $model;
}
This calls save:
public function save(array $options = array()) {
$query = $this->newQueryWithoutScopes();
.......
}
and that calls newQueryWithoutScope:
public function newQueryWithoutScopes() {
return $this->removeGlobalScopes($this->newQuery());
}
and of course removeGlobalScopes:
public function removeGlobalScopes($builder) {
foreach ($this->getGlobalScopes() as $scope) {
$scope->remove($builder, $this);
}
return $builder;
}
$scope->remove() is the remove method that we setup in our StatusColumnScope class. This is called to reverse the scoping but in our case I just overrode the query completely, setting it back to it's original query.