【WordPress】投稿保存時に内容をフィルターして変更する方法

add_filter( 'wp_insert_post_data',function($data){
    if( isset($data['post_content'])){
        ob_start(); // バッファリング開始
        var_dump( $data );
        $dump_text = ob_get_contents(); // バッファからデータ取得
        ob_end_clean(); // バッファクリアとバッファリングの停止
        $data['post_content'] = "<pre>\n".$dump_text. "\n</pre>\n".$data['post_content'];
    }
    return $data;
});

array(21) {
  ["post_author"]=>
  int(1)
  ["post_date"]=>
  string(19) "2023-05-25 07:42:56"
  ["post_date_gmt"]=>
  string(19) "2023-05-25 07:42:56"
  ["post_content"]=>
  string(26) "Hello World!
Hello World!"
  ["post_content_filtered"]=>
  string(0) ""
  ["post_title"]=>
  string(4) "test"
  ["post_excerpt"]=>
  string(12) "抜粋です"
  ["post_status"]=>
  string(7) "inherit"
  ["post_type"]=>
  string(8) "revision"
  ["comment_status"]=>
  string(6) "closed"
  ["ping_status"]=>
  string(6) "closed"
  ["post_password"]=>
  string(0) ""
  ["post_name"]=>
  string(14) "28-autosave-v1"
  ["to_ping"]=>
  string(0) ""
  ["pinged"]=>
  string(0) ""
  ["post_modified"]=>
  string(19) "2023-05-25 07:42:56"
  ["post_modified_gmt"]=>
  string(19) "2023-05-25 07:42:56"
  ["post_parent"]=>
  int(28)
  ["menu_order"]=>
  int(0)
  ["post_mime_type"]=>
  string(0) ""
  ["guid"]=>
  string(0) ""
}

Hello World!
Hello World!

add_filter( 'wp_insert_post_data',function($data){
    if( isset($data['post_content'])){
        $data['post_content'] = my_add_htag($data['post_content'],false);
    }
    return $data;
});