Illuminate/database (Laravel) full text search

FullTextSearch.php

<?php

namespace Models;

trait FullTextSearch
{
  /**
   * I did not write this! This is purely for reference
   * 
   * Source: https://arianacosta.com/php/laravel/tutorial-full-text-search-laravel-5/
   * 
   * define $searchable => [] columns on model, these must have a fulltext index
   */

  /**
   * Replaces spaces with full text search wildcards
   *
   * @param string $term
   * @return string
   */
  protected function fullTextWildcards($term)
  {
    // removing symbols used by MySQL
    $reservedSymbols = ['-', '+', '<', '>', '@', '(', ')', '~'];
    $term = str_replace($reservedSymbols, '', $term);

    $words = explode(' ', $term);

    foreach($words as $key => $word) {
      /*
       * applying + operator (required word) only big words
       * because smaller ones are not indexed by mysql
       */
      if(strlen($word) >= 3) {
        $words[$key] = '+' . $word . '*';
      }
    }

    $searchTerm = implode( ' ', $words);

    return $searchTerm;
  }

  /**
   * Scope a query that matches a full text search of term.
   *
   * @param \Illuminate\Database\Eloquent\Builder $query
   * @param string $term
   * @return \Illuminate\Database\Eloquent\Builder
   */
  public function scopeSearch($query, $term)
  {
    $columns = implode(',',$this->searchable);

    $searchableTerm = $this->fullTextWildcards($term);

    //select all columns for the result using ->select('*')
    return $query->select('*')->selectRaw("MATCH ({$columns}) AGAINST (? IN BOOLEAN MODE) AS relevance_score", [$searchableTerm])
      ->whereRaw("MATCH ({$columns}) AGAINST (? IN BOOLEAN MODE)", [$searchableTerm])
      ->orderBy('relevance_score','desc');
  }
}