relatableQuery() for two resource fields on same model in Laravel Nova

Question

I have a relationship between work 'days' and projects of different types. So my 'days' record has a reference to my 'projects' table twice because I have two different types of projects called 'Series' and 'Event'.

In my 'days' resource I've created two fields as such:

BelongsTo::make('Series','series',Project::class)->sortable()->nullable(),
BelongsTo::make('Event','event',Project::class)->sortable()->nullable(),

What I'm trying to do is filter the projects by their types so I've created this:

public static function relatableProjects(NovaRequest $request, $query){
    return $query->where('type', 'Series');
}

I've tried making relatableSeries and relatableEvents but they don't work. How can I make this connect to the fields correctly without having to create two separate tables for 'series' and 'events'.

The relatableQuery above winds up filtering both resource fields.

Answer 1

Because relatableQuery() is referencing a relatableModel() (so relatableProjects() references the Project model) I was able to create another model solely for the purpose of helping with this.

I created an Event model which references the same projects table and then was able to create a relatableEvents() method to use the where() filter query.

Note: I did have to also create an Event resource which references the Event model since this is how Nova works but was able to hide it from being accessed which you can find more information about here

See revised BelongsTo fields and new model below:

Day resource

    /**
     * Build a "relatable" query for the given resource.
     *
     * This query determines which instances of the model may be attached to other resources.
     *
     * @param  \Laravel\Nova\Http\Requests\NovaRequest  $request
     * @param  \Illuminate\Database\Eloquent\Builder  $query
     * @return \Illuminate\Database\Eloquent\Builder
     */
    public static function relatableProjects(NovaRequest $request, $query){
        return $query->where('type', 'Series');
    }

    /**
     * Build a "relatable" query for the given resource.
     *
     * This query determines which instances of the model may be attached to other resources.
     *
     * @param  \Laravel\Nova\Http\Requests\NovaRequest  $request
     * @param  \Illuminate\Database\Eloquent\Builder  $query
     * @return \Illuminate\Database\Eloquent\Builder
     */
    public static function relatableEvents(NovaRequest $request, $query){
        return $query->where('type', 'Event');
    }

    /**
     * Get the fields displayed by the resource.
     *
     * @param  \Illuminate\Http\Request  $request
     * @return array
     */
    public function fields(Request $request)
    {
        return [
            ID::make()->hideFromIndex()->hideFromDetail()->hideWhenUpdating(),
            BelongsTo::make('User','user',User::class)->sortable(),
            BelongsTo::make('Budget','budget',Budget::class)->sortable()->nullable(),
            BelongsTo::make('Series','series',Project::class)->sortable()->nullable(),
            BelongsTo::make('Event','event',Event::class)->sortable()->nullable(),
            DateTime::make('Last Updated','updated_at')->hideFromIndex()->readOnly(),
            new Panel('Schedule',$this->schedule()),
            new Panel('Time Entry',$this->timeEntries()),

        ];
    }

Event model

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class Event extends Model
{
    /**
     * The table associated with the model.
     *
     * @var string
     */
    protected $table = 'projects';

    protected $casts = [
        'starts_on' => 'date',
        'ends_on' => 'date',
    ];

    public function event(){
        return $this->belongsTo('App\Event');
    }

    public function project(){
        return $this->belongsTo('App\Project');
    }
}