Php Wordpress/Jetpack：我的代码的哪一部分导致Jetpack崩溃？

我已经创建了一个用于处理事件图像的自定义post类型（图像），我还添加了一个自定义图像上传器元字段，所有操作都完全按照我希望的方式进行，只是它会破坏jetpack。根据Jetpack的经验，我知道一个插件可能会产生意外的输出，导致Jetpack出现“-32700”错误，但我不知道是哪个部分的代码造成的。图像上载程序的代码为：

<?php
function add_custom_meta_boxes() {

// Define the custom attachment for posts
add_meta_box(
    'wp_image_attachment',
    'Custom Attachment',
    'wp_image_attachment',
    'images',
    'side'
);


} // end add_custom_meta_boxes
add_action('add_meta_boxes', 'add_custom_meta_boxes');

function wp_image_attachment() {

wp_nonce_field(plugin_basename(__FILE__), 'wp_image_attachment_nonce');

$html = '<p class="description">';
    $html .= 'Upload your image here.';
$html .= '</p>';
$html .= '<input type="file" id="wp_image_attachment" name="wp_image_attachment" value="" size="25">';

echo $html;

} // end wp_image_attachment


function save_custom_meta_data($id) {

/* --- security verification --- */
if(!wp_verify_nonce($_POST['wp_image_attachment_nonce'], plugin_basename(__FILE__))) {
  return $id;
} // end if

if(defined('DOING_AUTOSAVE') && DOING_AUTOSAVE) {
  return $id;
} // end if

if('page' == $_POST['post_type']) {
  if(!current_user_can('edit_page', $id)) {
    return $id;
  } // end if
} else {
    if(!current_user_can('edit_page', $id)) {
        return $id;
    } // end if
} // end if
/* - end security verification - */

// Make sure the file array isn't empty
if(!empty($_FILES['wp_image_attachment']['name'])) {

    // Setup the array of supported file types. In this case, it's just PDF.
    $supported_types = array('image/gif', 'image/jpeg', 'image/jpg', 'image/png');

    // Get the file type of the upload
    $arr_file_type = wp_check_filetype(basename($_FILES['wp_image_attachment']['name']));
    $uploaded_type = $arr_file_type['type'];

    // Check if the type is supported. If not, throw an error.
    if(in_array($uploaded_type, $supported_types)) {

        // Use the WordPress API to upload the file
        $upload = wp_upload_bits($_FILES['wp_image_attachment']['name'], null, file_get_contents($_FILES['wp_image_attachment']['tmp_name']));

        if(isset($upload['error']) && $upload['error'] != 0) {
            wp_die('There was an error uploading your file. The error is: ' . $upload['error']);
        } else {
            add_post_meta($id, 'wp_image_attachment', $upload);
            update_post_meta($id, 'wp_image_attachment', $upload);      
        } // end if/else

    } else {
        wp_die("The file type that you've uploaded is not an image.");
    } // end if/else

} // end if

} // end save_custom_meta_data
add_action('save_post', 'save_custom_meta_data');

function update_edit_form() {
echo ' enctype="multipart/form-data"';
} // end update_edit_form
add_action('post_edit_form_tag', 'update_edit_form');

?>

---

Booooo！新手失误！意外的输出似乎是由于我插件的那个部分被添加到了原始的自定义post-type部分，当然，它以

?> 

以上部分从

<?php