Upload a file from a URL to the WordPress media gallery. Supports images, PDFs, and other file types.

rs_upload_from_url.php

<?php

/**
 * This function uploads a file from a URL to the media library, designed to be placed in your own theme or plugin.
 * Metadata will be generated and images will generate thumbnails automatically.
 *
 * HOW TO USE:
 *    1. Add the function below to your theme or plugin
 *    2. Call the function and provide the URL to an image or other file.
 *    3. If successful, the attachment ID will be returned.
 *
 * BASIC USAGE:
 *    $attachment_id = rs_upload_from_url( "https://www.gstatic.com/webp/gallery/1.jpg" );
 *    if ( $attachment_id ) echo wp_get_attachment_image( $attachment_id, 'large' );
 *
 * DOWNLOAD AS A PLUGIN (optional):
 *    Below is a link to a separate plugin you can upload to your site to help get started. 
 *    It is a fully-functional example and demonstrates upload both JPG and WEBP image by using a "secret" url. 
 *    It also provides an easy way to delete the test images that were created.
 *    @see https://gist.github.com/RadGH/be30af96617b13e7848a4626ef179bbd
 *
 * To upload from a *LOCAL FILE PATH* instead of a URL:
 * @see: https://gist.github.com/RadGH/3b544c827193927d1772
 */


/**
 * Upload a file to the media library using a URL.
 * 
 * @version 1.3
 * @author  Radley Sustaire
 * @see     https://gist.github.com/RadGH/966f8c756c5e142a5f489e86e751eacb
 *
 * @param string $url           URL to be uploaded
 * @param null|string $title    Override the default post_title
 * @param null|string $content  Override the default post_content (Added in 1.3)
 * @param null|string $alt      Override the default alt text (Added in 1.3)
 *
 * @return int|false
 */
function rs_upload_from_url( $url, $title = null, $content = null, $alt = null ) {
	require_once( ABSPATH . "/wp-load.php");
	require_once( ABSPATH . "/wp-admin/includes/image.php");
	require_once( ABSPATH . "/wp-admin/includes/file.php");
	require_once( ABSPATH . "/wp-admin/includes/media.php");
	
	// Download url to a temp file
	$tmp = download_url( $url );
	if ( is_wp_error( $tmp ) ) return false;
	
	// Get the filename and extension ("photo.png" => "photo", "png")
	$filename = pathinfo($url, PATHINFO_FILENAME);
	$extension = pathinfo($url, PATHINFO_EXTENSION);
	
	// An extension is required or else WordPress will reject the upload
	if ( ! $extension ) {
		// Look up mime type, example: "/photo.png" -> "image/png"
		$mime = mime_content_type( $tmp );
		$mime = is_string($mime) ? sanitize_mime_type( $mime ) : false;
		
		// Only allow certain mime types because mime types do not always end in a valid extension (see the .doc example below)
		$mime_extensions = array(
			// mime_type         => extension (no period)
			'text/plain'         => 'txt',
			'text/csv'           => 'csv',
			'application/msword' => 'doc',
			'image/jpg'          => 'jpg',
			'image/jpeg'         => 'jpeg',
			'image/gif'          => 'gif',
			'image/png'          => 'png',
			'video/mp4'          => 'mp4',
		);
		
		if ( isset( $mime_extensions[$mime] ) ) {
			// Use the mapped extension
			$extension = $mime_extensions[$mime];
		}else{
			// Could not identify extension. Clear temp file and abort.
			wp_delete_file($tmp);
			return false;
		}
	}
	
	// Upload by "sideloading": "the same way as an uploaded file is handled by media_handle_upload"
	$args = array(
		'name' => "$filename.$extension",
		'tmp_name' => $tmp,
	);
	
	// Post data to override the post title, content, and alt text
	$post_data = array();
	if ( $title )   $post_data['post_title'] = $title;
	if ( $content ) $post_data['post_content'] = $content;
	
	// Do the upload
	$attachment_id = media_handle_sideload( $args, 0, null, $post_data );
	
	// Clear temp file
	wp_delete_file($tmp);
	
	// Error uploading
	if ( is_wp_error($attachment_id) ) return false;
	
	// Save alt text as post meta if provided
	if ( $alt ) {
		update_post_meta( $attachment_id, '_wp_attachment_image_alt', $alt );
	}
	
	// Success, return attachment ID
	return (int) $attachment_id;
}

Nice, thanks you!

Yeh! Still working 09.12.2023 ;) Thanks a lot!

Hello, how can I use this snippet? I mean I have put the code in the functions.php and tried to upload the media by going to Media > Library page, where's the button to upload from a URL? Am I missing something... Sorry I'm no code developer. Thanks!

@gilangramadhan There is no interface. You'll need to do some coding to make use of this. I'm sure there is a plugin out there that will let you upload files by url using the media uploader. What would work best for what you are trying to do?

Thanks for this! This is great, @RadGH! -- one minor suggestion: switch the @unlink's with wp_delete_file; this will allow you to remove silence operators from your code (and, more importantly, allow the path to be filterable via the wp_delete_file filter)

@philbirnie Great suggestion, thanks! I updated the script to use wp_delete_file instead of @unlink.

Dose it support .webp format like this one?
https://a2zaitools.com/wp-content/uploads/2024/02/Drafts-AI-1024x501.webp

@mdbadsha Yep, I just tested and webp images work just fine.

---

To anyone else interested, I created a plugin to test this function which is available at another gist URL:

https://gist.github.com/RadGH/be30af96617b13e7848a4626ef179bbd

Instructions and a screenshot of the results are displayed on the first comment:

https://gist.github.com/RadGH/be30af96617b13e7848a4626ef179bbd#gistcomment-4870147