einundzwanzig-portal/app/Http/Controllers/Api/LecturerController.php

<?php

namespace App\Http\Controllers\Api;

use App\Http\Controllers\Controller;
use App\Models\Lecturer;
use Illuminate\Database\Eloquent\Builder;
use Illuminate\Http\Request;

class LecturerController extends Controller
{
    /**
     * Display a listing of the resource.
     *
     * @return \Illuminate\Http\Response
     */
    public function index(Request $request)
    {
        return Lecturer::query()
                     ->select('id', 'name',)
                     ->orderBy('name')
                     ->when(
                         $request->search,
                         fn(Builder $query) => $query
                             ->where('name', 'like', "%{$request->search}%")
                     )
                     ->when(
                         $request->exists('selected'),
                         fn(Builder $query) => $query->whereIn('id', $request->input('selected', [])),
                         fn(Builder $query) => $query->limit(10)
                     )
                     ->get()
                     ->map(function (Lecturer $lecturer) {
                         $lecturer->image = $lecturer->getFirstMediaUrl('avatar', 'thumb');

                         return $lecturer;
                     });
    }

    /**
     * Store a newly created resource in storage.
     *
     * @param  \Illuminate\Http\Request  $request
     * @return \Illuminate\Http\Response
     */
    public function store(Request $request)
    {
        //
    }

    /**
     * Display the specified resource.
     *
     * @param  \App\Models\Lecturer  $lecturer
     * @return \Illuminate\Http\Response
     */
    public function show(Lecturer $lecturer)
    {
        //
    }

    /**
     * Update the specified resource in storage.
     *
     * @param  \Illuminate\Http\Request  $request
     * @param  \App\Models\Lecturer  $lecturer
     * @return \Illuminate\Http\Response
     */
    public function update(Request $request, Lecturer $lecturer)
    {
        //
    }

    /**
     * Remove the specified resource from storage.
     *
     * @param  \App\Models\Lecturer  $lecturer
     * @return \Illuminate\Http\Response
     */
    public function destroy(Lecturer $lecturer)
    {
        //
    }
}