Add/user tracking option api

_inc/lib/class.jetpack-user-event-tracking.php

@@ -0,0 +1,49 @@
+<?php
+
+class Jetpack_User_Event_Tracking {
+
+	private static $_cache = array();
+	const KEY = 'jetpack_event_tracking';
+
+	static function is_enabled( $user_id ) {
+		if ( isset( self::$_cache[ $user_id ] ) ) {
+			return self::$_cache[ $user_id ];
+		}
+		$user_tracking = get_user_meta( $user_id, self::KEY, true );
+		if ( ! is_numeric( $user_tracking ) ) {
+			$user_tracking = self::default_value();
+		}
+		self::$_cache[ $user_id ] = (bool) $user_tracking;
+		return (bool) $user_tracking();
+	}
+
+	static function is_disabled( $user_id ) {
+		return ! self::is_enabled( $user_id );
+	}
+
+	static function disable( $user_id ) {
+		// user opted out
+		self::set( $user_id, 0 );
+	}
+
+	static function enable( $user_id ) {
+		// user opted in
+		self::set( $user_id, 1 );
+	}
+
+	static private function set( $user_id, $value ) {
+		self::$_cache[ $user_id ] = (bool) $value;
+		update_user_meta( $user_id, self::KEY, $value );
+	}
+
+	static function default_value() {
+		/**
+		 * Return the default jetpack user event tracking opt out value.
+		 *
+		 * @since 6.0.0
+		 *
+		 * @param bool Default to false. (user tracking enabled)
+		 */
+		return apply_filters( 'jetpack_event_tracking', true );
+	}
+}

phpunit.xml.dist

@@ -13,6 +13,7 @@
 			<file>tests/php/test_class.jetpack-constants.php</file>
 			<file>tests/php/test_class.jetpack-connection-banner.php</file>
 			<file>tests/php/test_class.jetpack-options.php</file>
+			<file>tests/php/test_class.jetpack-user-event-tracking.php</file>
 		</testsuite>
 		<testsuite name="php-lint">
 			<file phpVersion="5.3.0" phpVersionOperator="lte">tests/php/test_php-lint.php</file>

sync/class.jetpack-sync-defaults.php

@@ -192,7 +192,8 @@ public static function get_constants_whitelist() {
 		'hosting_provider'                 => array( 'Jetpack_Sync_Functions', 'get_hosting_provider' ),
 		'locale'                           => 'get_locale',
 		'site_icon_url'                    => array( 'Jetpack_Sync_Functions', 'site_icon_url' ),
-		'roles'                            =>  array( 'Jetpack_Sync_Functions', 'roles' ),
+		'roles'                            => array( 'Jetpack_Sync_Functions', 'roles' ),
+		'default_user_event_tracking'      => array( 'Jetpack_Sync_functions', 'get_default_user_tracking_value' )
 	);
 
 

sync/class.jetpack-sync-functions.php

@@ -33,6 +33,11 @@ public static function get_shortcodes() {
 		return array_keys( $shortcode_tags );
 	}
 
+	public static function get_default_user_tracking_value() {
+		jetpack_require_lib(  'class.jetpack-user-event-tracking' );
+		return Jetpack_User_Event_Tracking::default_value();
+	}
+
 	/**
 	 * Removes any callback data since we will not be able to process it on our side anyways.
 	 */

sync/class.jetpack-sync-module-users.php

@@ -112,6 +112,8 @@ public function expand_user( $user ) {
 				$user->locale = get_user_locale( $user->ID );
 			}
 		}
+		jetpack_require_lib(  'class.jetpack-user-event-tracking' );
+		$user->jetpack_tracking_enabled = Jetpack_User_Event_Tracking::is_enabled( $user->ID );
 
 		return $user;
 	}
@@ -286,6 +288,11 @@ function maybe_save_user_meta( $meta_id, $user_id, $meta_key, $value ) {
 			$this->add_flags( $user_id, array( 'locale_changed' => true ) );
 		}
 
+		jetpack_require_lib( 'class.jetpack-user-event-tracking' );
+		if ( $meta_key === Jetpack_User_Event_Tracking::KEY ) {
+			$this->add_flags( $user_id, array( 'tracking_opt_out_changed' => true ) );
+		}
+
 		$user = get_user_by( 'id', $user_id );
 		if ( $meta_key === $user->cap_key  ) {
 			$this->add_flags( $user_id, array( 'capabilities_changed' => true ) );

tests/php.multisite.xml

@@ -14,6 +14,7 @@
             <file>php/test_class.jetpack-client-server.php</file>
             <file>php/test_class.jetpack-xmlrpc-server.php</file>
             <file>php/test_class.jetpack-heartbeat.php</file>
+			<file>tests/php/test_class.jetpack-user-event-tracking.php</file>
         </testsuite>
         <testsuite name="core-api">
             <directory phpVersion="5.6.0" phpVersionOperator=">=" prefix="test_" suffix=".php">tests/php/core-api</directory>

tests/php/test_class.jetpack-user-event-tracking.php

@@ -0,0 +1,36 @@
+<?php
+
+require dirname( __FILE__ ) . '/../../_inc/lib/class.jetpack-user-event-tracking.php';
+
+class WP_Test_Jetpack_User_Event_Tracking extends WP_UnitTestCase {
+	protected $user_id;
+
+	public function setUp() {
+		parent::setUp();
+
+		// create a user
+		$this->user_id = $this->factory->user->create();
+	}
+
+	public function test_default_value_is_disabled() {
+		$this->assertFalse( Jetpack_User_Event_Tracking::is_disabled( $this->user_id ) );
+		$this->assertTrue( Jetpack_User_Event_Tracking::is_enabled( $this->user_id ) );
+	}
+
+	public function test_enabeling_tracking() {
+		Jetpack_User_Event_Tracking::enable( $this->user_id );
+		$this->assertTrue( Jetpack_User_Event_Tracking::is_enabled( $this->user_id ) );
+	}
+
+	public function test_disabeling_tracking() {
+		Jetpack_User_Event_Tracking::disable( $this->user_id );
+		$this->assertFalse( Jetpack_User_Event_Tracking::is_enabled( $this->user_id ) );
+	}
+
+	public function test_filter_works_as_expected() {
+		// by default opt out every user
+		add_filter( 'jetpack_user_event_tracking_opt_out', '__return_true' );
+		$user_id = $this->factory->user->create();
+		$this->assertFalse( Jetpack_User_Event_Tracking::is_enabled( $user_id ) );
+	}
+}