OR 키워드 검색

or-search.php

<?php
/**
 * Plugin Name: OR 키워드 검색
 * Description: 입력된 키워드를 OR 조건으로 검색합니다.
 * Author:      changwoo
 * Author URI:  https://blog.changwoo.pe.kr
 */

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

add_action( 'admin_menu', 'or_search_admin_menu' );

/**
 * 메뉴 페이지 추가
 *
 * @return void
 */
function or_search_admin_menu() {
	add_menu_page(
		'OR 키워드 검색 샘플 페이지',
		'OR 검색',
		'administrator',
		'or-search',
		'or_search_output_page',
		'dashicons-search'
	);
}

/**
 * 메뉴 페이지 출력
 *
 * @return void
 */
function or_search_output_page() {
	$s     = isset( $_GET['s'] ) ? sanitize_text_field( $_GET['s'] ) : '';
	$items = array();
	$sql   = '';

	if ( $s ) {
		// Post content 에 대해서만 검색하려면 이 필터를 쓰세요.
		add_filter( 'posts_where', 'or_search_where_filter', 10, 2 );

		$query = new WP_Query(
			array(
				'post_type'     => 'post',
				'post_status'   => 'publish',
				's'             => $s,
				'orderby'       => 'date',
				'order'         => 'desc',
				'nopaging'      => true,      // 모든 검색된 포스트 한방에.
				'no_found_rows' => true,      // 총 포스트 수 계산 않음.
			)
		);

		// 필터를 썼으면 반드시 해제하세요.
		remove_filter( 'posts_where', 'or_search_where_filter' );

		$sql = $query->request;

		$keywords = array_filter( explode( ' ', $s ) );

		while ( $query->have_posts() ) {
			$query->the_post();
			$items[] = array(
				'post_id'   => get_the_ID(),
				'title'     => get_the_title(),
				'reference' => or_search_get_reference( get_the_content(), $keywords ),
			);
		}
	}

	$allwed_tags = array(
		'span' => array( 'class' => true ),
	);

	?>
    <style>
        #search-result {
            margin: 20px 0;
        }

        .or-search-found {
            color: red;
            background-color: yellow;
            font-weight: bold;
        }

        #sql-wrap {
            margin: 20px 0;
        }

        #sql-wrap > pre {
            display: inline;
            white-space: pre-line;
        }
    </style>
    <div class="wrap">
        <h1>OR 키워드 검색 예제</h1>
        <hr class="wp-header-end">
        <div>
            <form action="" method="get">
                <label for="s">키워드</label>:
                <input id="s"
                       name="s"
                       type="search"
                       placeholder="OR 검색할 키워드"
                       value="<?php echo esc_attr( $s ); ?>">
                <button class="button button-primary">검색</button>
                <input type="hidden" name="page" value="or-search">
				<?php wp_nonce_field( 'or-search', '_wpnonce', false ) ?>
            </form>
			<?php if ( $sql ) : ?>
                <div id="sql-wrap"><strong>쿼리</strong>:
                    <pre><?php echo esc_html( $sql ); ?></pre>
                </div>
			<?php endif; ?>
            <table id="search-result" class="wp-list-table widefat striped">
                <thead>
                <tr>
                    <td>ID</td>
                    <td>제목</td>
                    <td>발췌</td>
                </tr>
                </thead>
                <tbody>
				<?php if ( ! empty( $items ) ) : ?>
					<?php foreach ( $items as $item ): ?>
                        <tr>
                            <td><?php echo intval( $item['post_id'] ); ?></td>
                            <td><?php echo wp_kses( $item['title'], $allwed_tags ); ?></td>
                            <td><?php echo wp_kses( $item['reference'], $allwed_tags ); ?></td>
                        </tr>
					<?php endforeach; ?>
				<?php else: ?>
                    <td colspan="3">검색된 내용이 없습니다.</td>
				<?php endif; ?>
                </tbody>
            </table>
        </div>
    </div>
	<?php
}


/**
 * 포스트 내용에서 검색된 내용을 찾음.
 *
 * @param string        $input
 * @param array<string> $keywords
 *
 * @return string
 */
function or_search_get_reference( $input, $keywords ) {
	if ( ! $input ) {
		return $input;
	}

	$output = esc_html( $input );

	foreach ( $keywords as $keyword ) {
		$k      = esc_html( $keyword );
		$output = str_replace( $keyword, '<span class="or-search-found">' . $k . '</span>', $output );
	}

	return $output;
}


/**
 * @param string $where
 *
 * @return string
 */
function or_search_where_filter( $where ) {
	global $wpdb;

	$title     = "({$wpdb->posts}.post_title ";
	$content   = "({$wpdb->posts}.post_content ";
	$p2_offset = 0;

	while (
		false !== ( $p1 = strpos( $where, $title ) ) &&
		false !== ( $p2 = strpos( $where, $content, $p2_offset ) )
	) {
		$before = substr( $where, 0, $p1 );
		$after  = substr( $where, $p2 );
		$where  = $before . $after;

		$p2_offset = $p1 + 1;
	}

	return $where;
}