Upload attachment from external site

Question

For example, we have some image on the external site: http://site.com/image.png

How do I upload this image to my wordpress as an image attachment by php?

Image should be copied to my uploads folder, post added, meta generated.

Answer 1

You can media_sideload_image() function to upload your files ex:

$upload = media_sideload_image( $url, $post_id );

or you can use a plugin like Cache Images which uploads all external images to your server as attachments.