Added mechanism to specify a constant for affiliate ID to be used in …

…the Extensions page. Fixes #482.

includes/extensions.php

@@ -4,6 +4,17 @@
  *
  * @author Chris Olbekson <chris@x-team.com>
  */
+/**
+ * By defining the WP_STREAM_AFFILIATE_ID constant, links on the Extensions page
+ * will be appended with the ID specified.
+ *
+ * More details on the Stream Premium affiliate program here:
+ * https://wp-stream.com/affiliates/
+ *
+ * Uncomment the line below, and change the "1" to be your affiliate ID.
+ */
+
+//define( 'WP_STREAM_AFFILIATE_ID', 1 );
 
 class WP_Stream_Extensions {
 
@@ -100,6 +111,15 @@ function get_extension_api() {
 		return false;
 	}
 
+	/**
+	 * Gets the affiliate reference portion of a URL if the affiliate ID constant is set.
+	 *
+	 * @return string A query string of the format '?ref=1', where 1 is the affiliate ID
+	 */
+	function get_affiliate() {
+		return ( defined( 'WP_STREAM_AFFILIATE_ID' ) ? '?ref=' . urlencode( WP_STREAM_AFFILIATE_ID ) : '' );
+	}
+
 	/**
 	 * Filters the plugin install api
 	 *
@@ -133,7 +153,7 @@ function filter_plugin_api_info( $false, $action, $args ) {
 
 						return $api;
 					} else {
-						$message = '<p>' . sprintf( __( 'You must connect to your %s account to install extensions.', 'stream' ), '<strong>' . esc_html__( 'Stream Premium', 'stream' ) . '</strong>' ) . '</p><p>' . esc_html__( "Don't have an account?", 'stream' ) . '</p><p><a href="https://wp-stream.com/join/" target="_blank" class="button">' . esc_html__( 'Join Stream Premium', 'stream' ) . '</a></p>';
+						$message = '<p>' . sprintf( __( 'You must connect to your %s account to install extensions.', 'stream' ), '<strong>' . esc_html__( 'Stream Premium', 'stream' ) . '</strong>' ) . '</p><p>' . esc_html__( "Don't have an account?", 'stream' ) . '</p><p><a href="https://wp-stream.com/join/' . $this->get_affiliate() . '" target="_blank" class="button">' . esc_html__( 'Join Stream Premium', 'stream' ) . '</a></p>';
 						wp_die( $message, 'Stream Extension Installation', array( 'response' => 200, 'back_link' => true ) ); // xss ok
 					}
 				}
@@ -210,7 +230,7 @@ function extensions_display_header( $extensions ) {
 		<?php if ( ! $this->verify_membership() ) : ?>
 			<p class="description">
 			<?php esc_html_e( "Connect your Stream Premium account and authorize this domain to install and receive automatic updates for premium extensions. Don't have an account?", 'stream' ) ?>
-				<a href="<?php echo esc_url( self::API_TRANSPORT . self::API_DOMAIN . '/join/' ) ?>" class="stream-premium-join"><?php esc_html_e( 'Join Stream Premium', 'stream' ) ?></a>
+				<a href="<?php echo esc_url( self::API_TRANSPORT . self::API_DOMAIN . '/join/' . $this->get_affiliate() ) ?>" class="stream-premium-join"><?php esc_html_e( 'Join Stream Premium', 'stream' ) ?></a>
 			</p>
 		<?php else : ?>
 			<p class="description" style="color: green;">
@@ -234,7 +254,7 @@ function extensions_display_body( $extensions ) {
 			<p>
 				<em><?php esc_html_e( 'Sorry, there was a problem loading the list of extensions.', 'stream' ) ?></em></p>
 			<p>
-				<a class="button button-primary" href="<?php echo esc_url( self::API_TRANSPORT . self::API_DOMAIN . '/#extensions' ) ?>" target="_blank"><?php esc_html_e( 'Browse All Extensions', 'stream' ) ?></a>
+				<a class="button button-primary" href="<?php echo esc_url( self::API_TRANSPORT . self::API_DOMAIN . '/#extensions' . $this->get_affiliate() ) ?>" target="_blank"><?php esc_html_e( 'Browse All Extensions', 'stream' ) ?></a>
 			</p>
 			<?php
 			return;