Validate Easy Digital Downloads License Key Field in a Gravity Forms Submission

gf-validate-edd-license-key.php

/**
 * Validate a Gravity Forms license submission against EDD remote validation
 *
 * In Gravity Forms, for the text field you want to use as the license key entry,
 * go to Advanced tab, check the "Allow field to be populated dynamically" checkbox,
 * then enter the value as `edd-{download_id}`, where {download_id} is the, you guessed
 * it, EDD Download ID.
 *
 * @param  array	$is_valid_and_form_array Gravity Forms passes an array with two keys: `is_valid` (boolean) and `form` (Gravity Forms form array)
 * @return array	Same format as incoming.
 * @ref		https://gist.github.com/zackkatz/f881fd7e221ca3dd6eec
 */
function extendd_validate_edd_license( $is_valid_and_form_array ) {

	extract( $is_valid_and_form_array );
	$edd_software_licensing = class_exists( 'EDD_Software_Licensing' ) ? edd_software_licensing() : false;

	foreach ( $form['fields'] as &$field ) {

		if ( strpos( $field['cssClass'], 'edd-license' ) !== false && $field['id'] == 6 ) {

			$download_title	= esc_attr( $_POST['input_4'] );
			$download 			= get_page_by_title( $download_title, null, $post_type = 'download' );
			$download_id 		= $download->ID;

			// Get the submitted value from the posted data
			$license = esc_attr( $_POST['input_' . $field['id'] ] );

			if ( empty( $license ) && !empty( $field['isRequired'] ) ) {
				$field['validation_message'] = __( 'Your license key is required.' );
				break;
			}
			
			// Lets make sure the license key is part of the download selected
			if ( $edd_software_licensing ) {
				$temp_download_id		= $edd_software_licensing->get_download_by_license( $license );
				$key_matches_plugin 	= $edd_software_licensing->check_item_name( $temp_download_id, $download_title );
			
				if ( !$key_matches_plugin ) {
					$is_valid = false;
					$field['failed_validation'] = true;
					$field['validation_message'] = sprintf( 'Invalid license key for selected plugin "%s".', $download_title );
					break;
				}
			}

			// data to send in our API request
			$api_params = array(
				'edd_action'	=> 'check_license',
				'license' 		=> $license,
				'item_name' 	=> urlencode( $download_title ),
			);

			// Call the custom API.
			$response = wp_remote_post( 'http://gravityview.co', array( 'timeout' => 35, 'sslverify' => false, 'body' => $api_params ) );

			// make sure the response came back okay
			if ( is_wp_error( $response ) ) {
				continue;
			}

			$license_data = json_decode( wp_remote_retrieve_body( $response ) );

			// Invalid response
			if ( !is_object( $license_data ) ) {
				continue;
			}

			// The license data
			switch( $license_data->license ) {

				// Licenses are invalid if they're invalid or expired.
				case 'invalid':
					$is_valid = false;
					$field['failed_validation'] = true;
					$field['validation_message'] = __( 'The license you entered is invalid.' );
					break;

				case 'expired':
					$is_valid = false;
					$field['failed_validation'] = true;
					$field['validation_message'] = sprintf( 'The license you entered expired on %s. Please <a href="%s">login</a> and <a href="%s">renew your license</a> for continued updates and support.',
						date( 'F j, Y', strtotime( $license_data->expires ) ),
						esc_url( site_url( '/my-account/' ) ),
						esc_url( add_query_arg( array( 'edd_license_key' => $license, 'download_id' => $download_id ), site_url( '/checkout/' ) ) )
					);
					break;
			}
		}
	}

	return array( "is_valid" => $is_valid, "form" => $form );
}
add_filter( 'gform_validation', 'extendd_validate_edd_license' );