Duplicar Posts do WordPress sem Usar Plugins Imprimir

Para isso, basta inserir o código abaixo no arquivo functions.php do seu tema.

Lembre-se de antes fazer um backup de seu site e banco de dados

/ DUPLICADOR DE POST WORDPRESS 

function rudr_metabox_content($post) {  
 
	// get all blog post tags as an array of objects
	$all_tags = get_terms( array('taxonomy' => 'post_tag', 'hide_empty' => 0) ); 
 
	// get all tags assigned to a post
	$all_tags_of_post = get_the_terms( $post->ID, 'post_tag' );  
 
	// create an array of post tags ids
	$ids = array();
	if ( $all_tags_of_post ) {
		foreach ($all_tags_of_post as $tag ) {
			$ids[] = $tag->term_id;
		}
	}
 
	// HTML
	echo '<div id="taxonomy-post_tag" class="categorydiv">';
	echo '<input type="hidden" name="tax_input[post_tag][]" value="0" />';
	echo '<ul>';
	foreach( $all_tags as $tag ){
		// unchecked by default
		$checked = "";
		// if an ID of a tag in the loop is in the array of assigned post tags - then check the checkbox
		if ( in_array( $tag->term_id, $ids ) ) {
			$checked = " checked='checked'";
		}
		$id = 'post_tag-' . $tag->term_id;
		echo "<li id='{$id}'>";
		echo "<label><input type='checkbox' name='tax_input[post_tag][]' id='in-$id'". $checked ." value='$tag->slug' /> $tag->name</label><br />";
		echo "</li>";
	}
	echo '</ul></div>'; // end HTML
}

/*
 * Function creates post duplicate as a draft and redirects then to the edit post screen
 */
function rd_duplicate_post_as_draft(){
	global $wpdb;
	if (! ( isset( $_GET['post']) || isset( $_POST['post'])  || ( isset($_REQUEST['action']) && 'rd_duplicate_post_as_draft' == $_REQUEST['action'] ) ) ) {
		wp_die('No post to duplicate has been supplied!');
	}
 
	/*
	 * Nonce verification
	 */
	if ( !isset( $_GET['duplicate_nonce'] ) || !wp_verify_nonce( $_GET['duplicate_nonce'], basename( __FILE__ ) ) )
		return;
 
	/*
	 * get the original post id
	 */
	$post_id = (isset($_GET['post']) ? absint( $_GET['post'] ) : absint( $_POST['post'] ) );
	/*
	 * and all the original post data then
	 */
	$post = get_post( $post_id );
 
	/*
	 * if you don't want current user to be the new post author,
	 * then change next couple of lines to this: $new_post_author = $post->post_author;
	 */
	$current_user = wp_get_current_user();
	$new_post_author = $current_user->ID;
 
	/*
	 * if post data exists, create the post duplicate
	 */
	if (isset( $post ) && $post != null) {
 
		/*
		 * new post data array
		 */
		$args = array(
			'comment_status' => $post->comment_status,
			'ping_status'    => $post->ping_status,
			'post_author'    => $new_post_author,
			'post_content'   => $post->post_content,
			'post_excerpt'   => $post->post_excerpt,
			'post_name'      => $post->post_name,
			'post_parent'    => $post->post_parent,
			'post_password'  => $post->post_password,
			'post_status'    => 'draft',
			'post_title'     => $post->post_title,
			'post_type'      => $post->post_type,
			'to_ping'        => $post->to_ping,
			'menu_order'     => $post->menu_order
		);
 
		/*
		 * insert the post by wp_insert_post() function
		 */
		$new_post_id = wp_insert_post( $args );
 
		/*
		 * get all current post terms ad set them to the new post draft
		 */
		$taxonomies = get_object_taxonomies($post->post_type); // returns array of taxonomy names for post type, ex array("category", "post_tag");
		foreach ($taxonomies as $taxonomy) {
			$post_terms = wp_get_object_terms($post_id, $taxonomy, array('fields' => 'slugs'));
			wp_set_object_terms($new_post_id, $post_terms, $taxonomy, false);
		}
 
		/*
		 * duplicate all post meta just in two SQL queries
		 */
		$post_meta_infos = $wpdb->get_results("SELECT meta_key, meta_value FROM $wpdb->postmeta WHERE post_id=$post_id");
		if (count($post_meta_infos)!=0) {
			$sql_query = "INSERT INTO $wpdb->postmeta (post_id, meta_key, meta_value) ";
			foreach ($post_meta_infos as $meta_info) {
				$meta_key = $meta_info->meta_key;
				if( $meta_key == '_wp_old_slug' ) continue;
				$meta_value = addslashes($meta_info->meta_value);
				$sql_query_sel[]= "SELECT $new_post_id, '$meta_key', '$meta_value'";
			}
			$sql_query.= implode(" UNION ALL ", $sql_query_sel);
			$wpdb->query($sql_query);
		}
 
 
		/*
		 * finally, redirect to the edit post screen for the new draft
		 */
		wp_redirect( admin_url( 'post.php?action=edit&post=' . $new_post_id ) );
		exit;
	} else {
		wp_die('Post creation failed, could not find original post: ' . $post_id);
	}
}
add_action( 'admin_action_rd_duplicate_post_as_draft', 'rd_duplicate_post_as_draft' );
 
/*
 * Add the duplicate link to action list for post_row_actions
 */
function rd_duplicate_post_link( $actions, $post ) {
	if (current_user_can('edit_posts')) {
		$actions['duplicate'] = '<a href="' . wp_nonce_url('admin.php?action=rd_duplicate_post_as_draft&post=' . $post->ID, basename(__FILE__), 'duplicate_nonce' ) . '" title="Duplicar o item" rel="permalink">Duplicar</a>';
	}
	return $actions;
}
 
add_filter( 'post_row_actions', 'rd_duplicate_post_link', 10, 2 );