Laravel 5.5 検索機能を実装してみた

<?php

use Illuminate\Support\Facades\Schema;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Database\Migrations\Migration;

class CreateRecipesTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::create('recipes', function (Blueprint $table) {
            $table->increments('id');
            $table->integer('user_id')->unsigned()->index();
            $table->string('name');
            $table->timestamps();

            // 外部キー制約
            $table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');
        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::dropIfExists('recipes');
    }
}

<?php

use Illuminate\Support\Facades\Schema;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Database\Migrations\Migration;

class CreateIngredientsTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::create('ingredients', function (Blueprint $table) {
            $table->increments('id');
            $table->integer('recipe_id')->unsigned()->index();
            $table->string('ingredient', 255);
            $table->timestamps();

            // 外部キー制約
            $table->foreign('recipe_id')->references('id')->on('recipes')->onDelete('cascade');
        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::dropIfExists('ingredients');
    }
}

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class Recipe extends Model
{
    protected $fillable = ['user_id', 'name'];

    public function user()
    {
        return $this->belongsTo(User::class);
    }

    public function ingredients()
    {
        return $this->hasMany(Ingredient::class);
    }
}

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class Ingredient extends Model
{
    protected $fillable = ['recipe_id', 'ingredient'];

    public function recipe()
    {
        return $this->belongsTo(Recipe::class);
    }
}

//検索機能
Route::get('paginate', 'SearchController@index')->name('search.index');

<?php

namespace App\Http\Controllers;

use Illuminate\Http\Request;
use Illuminate\Support\Facades\DB; //付け加える

use App\Recipe;//付け加える

class SearchController extends Controller
{
    public function index(Request $request)
    {
        //キーワードを取得
        $keyword = $request->input('keyword');

        //もしキーワードが入力されている場合
        if(!empty($keyword))
        {   
            //料理名から検索
            $recipes = DB::table('recipes')
                    ->where('name', 'like', '%'.$keyword.'%')
                    ->paginate(4);

            //リレーション関係にあるテーブルの材料名から検索
            $recipes = Recipe::whereHas('ingredients', function ($query) use ($keyword){
                $query->where('ingredient', 'like','%'.$keyword.'%');
            })->paginate(4);

        }else{//キーワードが入力されていない場合
            $recipes = DB::table('recipes')->paginate(4);
        }
        //検索フォームへ
        return view('search.index',[
            'recipes' => $recipes,
            'keyword' => $keyword,
            ]);
    }
}

   //検索フォーム
   <div class="container">
       <div class="row">
            <div class="col-md-3">   
                <form class="form-inline">
                    <div class="form-group">
                    <input type="text" name="keyword" value="{{ $keyword }}"
                    placeholder="料理名か材料名を入力">
                    <input type="submit" value="検索" >
                    </div>
                </form>
            </div>
        </div>
    </div>

    //料理名の表示
    <div class="container">
        @if(count($recipes) > 0)
          <div class="row">
            @foreach($recipes as $recipe)
            <div class="col-md-3">
              {{ $recipe->name }}
            </div>
            @endforeach
           </div>
        @endif
　　　　　　　　　　　　　　　　//ページネーション機能
        <div class="paginate">
            {{ $recipes->render('pagination::bootstrap-4') }}
        </div>
     </div>