Improve how clauses for related model columns are specified.

[atrauzzi]

I'm looking to filter results of a particular model based on whether there is a match in a relation it has.

The code I was hoping to write would look something like this:

$query->whereIn('permissions.name', $this->permissions);

Simply put, this would conveniently add to the query a join and a whereIn clause that uses the configured relation permissions.

While I know I could write out a join manually, I wasn't able to find anywhere in the L4 documentation or on IRC a shorthand way to accomplish this. I was thinking this might be a nice expressive way to reduce the amount of code needed for situations like this.

[danharper]

Had this problem today, the solution is (context):

Task::select('tasks.*')
    ->join('properties', 'properties.id', '=', 'tasks.property_id')
    ->where('properties.town', 'Portsmouth')
    ->where('tasks.state', 'Active')
    ->get();

Compare to how it's handled in FuelPHP:

// FuelPHP
Model_Task::find()
    ->related('property')
    ->where('property.town', 'Portsmouth')
    ->where('state', 'Active')
    ->get();

I think having a similar related() method for Eloquent would be ideal. It'd perform the join and set the select() with only the parent model's columns. And when setting a where(), if the column field (first arg) doesn't contain a ., it can be assumed it belongs to the parent model.

Or even having the related() method optional, and have the where intelligently guess at the correct related model?

[taylorotwell]

This will be solved if we support constraints on the has method, which there is a pull request for.