WordPress カスタム投稿でCSV一括ダウンロードする

if ( !function_exists( 'cat_manage_posts_extra_tablenav' ) ) {
	function cat_manage_posts_extra_tablenav($which) {
	  global $typenow;
	  if ( $typenow === 'cat' && $which === 'top' ) {
	    wp_nonce_field('posttype-cat-csv-download-nonce-action', 'posttype-cat-csv-download-nonce-key');
	    echo '<input type="submit" name="export_all_posts" class="button" value="CSV ダウンロード" />';
	  }
	}
	add_action( 'manage_posts_extra_tablenav', 'cat_manage_posts_extra_tablenav' , 10, 2 );
}

if ( !function_exists( 'posttype_cat_csv_download' ) ) {
	function posttype_cat_csv_download() {
		if (isset($_GET['posttype-cat-csv-download-nonce-key']) && $_GET['posttype-cat-csv-download-nonce-key']) :
			if (check_admin_referer('posttype-cat-csv-download-nonce-action', 'posttype-cat-csv-download-nonce-key')) :
				if ( isset( $_GET['export_all_posts'] ) ) :
					$csv = array();
					$args = array(
				        'post_type' => 'cat',
			            'posts_per_page' => -1,
			        );
					$query = new WP_Query($args);
					if($query -> have_posts()):
						$csv = array(
							0 => array(
								'post_id',
								'post_name',
								'post_author',
								'post_date',
								'post_type',
								'post_status',
								'post_title',
								'cat_age',
								'cat_sex',
								'tax_cat_genre',
							),
						);
						while($query -> have_posts()): $query -> the_post();
							$terms = get_the_terms(get_the_ID(), 'cat_genre');
							$terms_array = array();
							if ( $terms ) :
							foreach ( $terms as $term ) {
								array_push($terms_array, $term->name);
							}
							endif;
							$result_terms = implode( ',', $terms_array );
							$cat_age = get_post_meta( get_the_ID(), 'cat_age', true );
							$cat_sex = get_post_meta( get_the_ID(), 'cat_sex', true );
							$csv += array(
									get_the_ID() => array(
									get_the_ID(),
									get_post( get_the_ID() )->post_name,
									get_the_author(),
									get_the_date(),
									get_post_type(),
									get_post_status(),
									get_the_title(),
									$cat_age,
									$cat_sex,
									$result_terms,
								),
							);
						endwhile;
					endif;
					wp_reset_postdata();
					try {
						$csvFileName = dirname(__FILE__).'/posttype_cat_download.csv';
				    $res = fopen($csvFileName, 'w');
				    if ($res === FALSE) {
					    throw new Exception('ファイルの書き込みに失敗しました。');
				    }
				    foreach($csv as $k => $v) {
					    fputcsv($res, $v);
				    }
				    fclose($res);
				    header('Content-Type: application/octet-stream');
				    header('Content-Disposition: attachment; filename="posttype_cat_download.csv"');
				    header('Pragma: no-cache');
				    header('Expires: 0');
				    header('Content-Length: ' . filesize($csvFileName));
				    readfile($csvFileName);
				    unlink($csvFileName);
				    exit;
				    } catch(Exception $e) {
// 				        echo $e->getMessage();
				    }
				endif;
			endif;
		endif;
	}
	add_action( 'init', 'posttype_cat_csv_download' );
}