add ability to filter for client-side flags only

Author: eli-darkly

src/LaunchDarkly/FeatureFlag.php

@@ -31,6 +31,9 @@ class FeatureFlag
     protected $_trackEvents = false;
     /** @var int | null */
     protected $_debugEventsUntilDate = null;
+    /** @var bool */
+    protected $_clientSide = false;
+
     // Note, trackEvents and debugEventsUntilDate are not used in EventProcessor, because
     // the PHP client doesn't do summary events. However, we need to capture them in case
     // they want to pass the flag data to the front end with allFlagsState().
@@ -47,7 +50,8 @@ protected function __construct($key,
                                    array $variations,
                                    $deleted,
                                    $trackEvents,
-                                   $debugEventsUntilDate)
+                                   $debugEventsUntilDate,
+                                   $clientSide)
     {
         $this->_key = $key;
         $this->_version = $version;
@@ -62,6 +66,7 @@ protected function __construct($key,
         $this->_deleted = $deleted;
         $this->_trackEvents = $trackEvents;
         $this->_debugEventsUntilDate = $debugEventsUntilDate;
+        $this->_clientSide = $clientSide;
     }
 
     public static function getDecoder()
@@ -80,7 +85,8 @@ public static function getDecoder()
                 $v['variations'] ?: [],
                 $v['deleted'],
                 isset($v['trackEvents']) && $v['trackEvents'],
-                isset($v['debugEventsUntilDate']) ? $v['debugEventsUntilDate'] : null
+                isset($v['debugEventsUntilDate']) ? $v['debugEventsUntilDate'] : null,
+                isset($v['clientSide']) && $v['clientSide']
             );
         };
     }
@@ -252,4 +258,12 @@ public function getDebugEventsUntilDate()
     {
         return $this->_debugEventsUntilDate;
     }
+
+    /**
+     * @return boolean
+     */
+    public function isClientSide()
+    {
+        return $this->_clientSide;
+    }
 }

src/LaunchDarkly/LDClient.php

@@ -282,9 +282,12 @@ public function allFlags($user)
      * The most common use case for this method is to bootstrap a set of client-side feature flags from a back-end service.
      * To convert the state object into a JSON data structure, call its toJson() method.
      * @param $user LDUser the end user requesting the feature flags
+     * @param $options array optional properties affecting how the state is computed; set
+     *   <code>'clientSideOnly' => true</code> to specify that only flags marked for client-side use
+     *   should be included (by default, all flags are included)
      * @return FeatureFlagsState a FeatureFlagsState object (will never be null; see FeatureFlagsState.isValid())
      */
-    public function allFlagsState($user)
+    public function allFlagsState($user, $options = array())
     {
         if (is_null($user) || is_null($user->getKey())) {
             $this->_logger->warn("allFlagsState called with null user or null/empty user key! Returning empty state");
@@ -304,7 +307,11 @@ public function allFlagsState($user)
         }
 
         $state = new FeatureFlagsState(true);
+        $clientOnly = isset($options['clientSideOnly']) && $options['clientSideOnly'];
         foreach ($flags as $key => $flag) {
+            if ($clientOnly && !$flag->isClientSide()) {
+                continue;
+            }
             $result = $flag->evaluate($user, $this->_featureRequester);
             $state->addFlag($flag, $result);
         }

tests/LDClientTest.php

@@ -164,6 +164,32 @@ public function testAllFlagsStateReturnsState()
         $this->assertEquals($expectedState, $state->jsonSerialize());
     }
 
+    public function testAllFlagsStateCanFilterForClientSideFlags()
+    {
+        $flag1Json = array('key' => 'server-side-1', 'on' => false, 'offVariation' => 0, 'variations' => array('a'), 'clientSide' => false);
+        $flag1 = FeatureFlag::decode($flag1Json);
+        $flag2Json = array('key' => 'server-side-2', 'on' => false, 'offVariation' => 0, 'variations' => array('b'), 'clientSide' => false);
+        $flag2 = FeatureFlag::decode($flag2Json);
+        $flag3Json = array('key' => 'client-side-1', 'on' => false, 'offVariation' => 0, 'variations' => array('value1'), 'clientSide' => true);
+        $flag3 = FeatureFlag::decode($flag3Json);
+        $flag4Json = array('key' => 'client-side-2', 'on' => false, 'offVariation' => 0, 'variations' => array('value2'), 'clientSide' => true);
+        $flag4 = FeatureFlag::decode($flag4Json);
+        MockFeatureRequester::$flags = array(
+            $flag1->getKey() => $flag1, $flag2->getKey() => $flag2, $flag3->getKey() => $flag3, $flag4->getKey() => $flag4
+        );
+        $client = new LDClient("someKey", array(
+            'feature_requester_class' => MockFeatureRequester::class,
+            'events' => false
+            ));
+
+        $builder = new LDUserBuilder(3);
+        $user = $builder->build();
+        $state = $client->allFlagsState($user, array('clientSideOnly' => true));
+         
+        $this->assertTrue($state->isValid());
+        $this->assertEquals(array('client-side-1' => 'value1', 'client-side-2' => 'value2'), $state->toValuesMap());
+    }
+
     public function testOnlyValidFeatureRequester()
     {
         $this->setExpectedException(InvalidArgumentException::class);