Support impressions disabled

CHANGES.txt

@@ -1,3 +1,6 @@
+x.x.x (Unreleased)
+  - Added support for the new impressions tracking toggle available on feature flags.
+
 7.4.0 (Apr 15, 2026)
   - Added support for PHP 8.5 version, removing deprecated warning messages.
 

src/SplitIO/Grammar/Split.php

@@ -33,6 +33,8 @@ class Split
     private $configurations = null;
     private $sets = null;
 
+    private $impressionsDisabled = false;
+
     public function __construct(array $split)
     {
         SplitApp::logger()->debug(print_r($split, true));
@@ -52,7 +54,10 @@ public function __construct(array $split)
         $this->configurations = isset($split['configurations']) && count($split['configurations']) > 0 ?
             $split['configurations'] : null;
         $this->sets = isset($split['sets']) ? $split['sets'] : array();
-
+        // Only an explicit boolean true disables impression tracking. Any other value
+        // (numbers, strings, null, missing or malformed) leaves impressions tracked.
+        $this->impressionsDisabled = isset($split['impressionsDisabled']) && $split['impressionsDisabled'] === true;
+
         SplitApp::logger()->info("Constructing Feature Flag: ".$this->name);
 
         if (isset($split['conditions']) && is_array($split['conditions'])) {
@@ -182,4 +187,12 @@ public function getSets()
     {
         return $this->sets;
     }
+
+    /**
+     * @return bool
+     */
+    public function impressionsDisabled()
+    {
+        return $this->impressionsDisabled;
+    }
 }

src/SplitIO/Sdk/Client.php

@@ -7,6 +7,7 @@
 use SplitIO\Sdk\Events\EventQueueMessage;
 use SplitIO\Sdk\QueueMetadataMessage;
 use SplitIO\Sdk\Impressions\Impression;
+use SplitIO\Sdk\Impressions\DecoratedImpression;
 use SplitIO\TreatmentImpression;
 use SplitIO\Sdk\Impressions\ImpressionLabel;
 use SplitIO\Grammar\Condition\Partition\TreatmentEnum;
@@ -134,7 +135,8 @@ private function doEvaluation($operation, $key, $featureFlagName, $attributes)
                 $bucketingKey
             );
 
-            $this->registerData($impression, $attributes);
+            $disabled = isset($result['impressionsDisabled']) && $result['impressionsDisabled'];
+            $this->registerData(new DecoratedImpression($impression, $disabled), $attributes);
             return array(
                 'treatment' => $result['treatment'],
                 'config' => $result['config'],
@@ -155,7 +157,7 @@ private function doEvaluation($operation, $key, $featureFlagName, $attributes)
                 ImpressionLabel::EXCEPTION,
                 $bucketingKey
             );
-            $this->registerData($impression, $attributes);
+            $this->registerData(new DecoratedImpression($impression, false), $attributes);
         } catch (\Exception $e) {
             SplitApp::logger()->critical(
                 "An error occurred when attempting to log impression for " .
@@ -237,12 +239,33 @@ private function doInputValidationForTreatments($key, $featureFlagNames, $operat
         );
     }
 
-    private function registerData($impressions, $attributes)
+    private function registerData($decoratedImpressions, $attributes)
     {
         try {
-            TreatmentImpression::log($impressions, $this->queueMetadata);
-            if (isset($this->impressionListener)) {
-                $this->impressionListener->sendDataToClient($impressions, $attributes);
+            // Normalize to array
+            if (!is_array($decoratedImpressions)) {
+                $decoratedImpressions = array($decoratedImpressions);
+            }
+
+            // Partition: all go to listener, only enabled go to log
+            $forListener = array();
+            $forLog = array();
+            foreach ($decoratedImpressions as $decorated) {
+                $impression = $decorated->getImpression();
+                $forListener[] = $impression;
+                if (!$decorated->isDisabled()) {
+                    $forLog[] = $impression;
+                }
+            }
+
+            // Log enabled impressions to Redis
+            if (!empty($forLog)) {
+                TreatmentImpression::log($forLog, $this->queueMetadata);
+            }
+
+            // Send all impressions to listener
+            if (isset($this->impressionListener) && !empty($forListener)) {
+                $this->impressionListener->sendDataToClient($forListener, $attributes);
             }
         } catch (\Exception $e) {
             SplitApp::logger()->critical(
@@ -526,18 +549,20 @@ private function processEvaluations(
         $evaluations
     ) {
         $result = array();
-        $impressions = array();
+        $decoratedImpressions = array();
         foreach ($evaluations as $featureFlagName => $evalResult) {
             if (InputValidator::isSplitFound($evalResult['impression']['label'], $featureFlagName, $operation)) {
                 // Creates impression
-                $impressions[] = $this->createImpression(
+                $impression = $this->createImpression(
                     $matchingKey,
                     $featureFlagName,
                     $evalResult['treatment'],
                     $evalResult['impression']['changeNumber'],
                     $evalResult['impression']['label'],
                     $bucketingKey
                 );
+                $disabled = isset($evalResult['impressionsDisabled']) && $evalResult['impressionsDisabled'];
+                $decoratedImpressions[] = new DecoratedImpression($impression, $disabled);
                 $result[$featureFlagName] = array(
                     'treatment' => $evalResult['treatment'],
                     'config' => $evalResult['config'],
@@ -546,7 +571,7 @@ private function processEvaluations(
                 $result[$featureFlagName] = array('treatment' => TreatmentEnum::CONTROL, 'config' => null);
             }
         }
-        $this->registerData($impressions, $attributes);
+        $this->registerData($decoratedImpressions, $attributes);
         return $result;
     }
 }

src/SplitIO/Sdk/Evaluator.php

@@ -108,11 +108,13 @@ private function evalTreatment($key, $bucketingKey, $split, ?array $attributes =
 
         if (is_null($split)) {
             $result['impression']['label'] = ImpressionLabel::SPLIT_NOT_FOUND;
+            $result['impressionsDisabled'] = false;
             return $result;
         }
         try {
             $configs = $split->getConfigurations();
             $result['impression']['changeNumber'] = $split->getChangeNumber();
+            $result['impressionsDisabled'] = $split->impressionsDisabled();
             if ($split->killed()) {
                 $defaultTreatment = $split->getDefaultTratment();
                 $result['treatment'] = $defaultTreatment;

src/SplitIO/Sdk/Impressions/DecoratedImpression.php

@@ -0,0 +1,47 @@
+<?php
+namespace SplitIO\Sdk\Impressions;
+
+/**
+ * Class DecoratedImpression
+ * Wraps an Impression with its disabled flag for routing purposes.
+ * @package SplitIO\Sdk\Impressions
+ */
+class DecoratedImpression
+{
+    /**
+     * @var Impression
+     */
+    private $impression;
+
+    /**
+     * @var bool
+     */
+    private $disabled;
+
+    /**
+     * DecoratedImpression constructor.
+     * @param Impression $impression
+     * @param bool $disabled
+     */
+    public function __construct(Impression $impression, $disabled)
+    {
+        $this->impression = $impression;
+        $this->disabled = (bool) $disabled;
+    }
+
+    /**
+     * @return Impression
+     */
+    public function getImpression()
+    {
+        return $this->impression;
+    }
+
+    /**
+     * @return bool
+     */
+    public function isDisabled()
+    {
+        return $this->disabled;
+    }
+}

src/SplitIO/Sdk/Manager/LocalhostSplitManager.php

@@ -66,7 +66,10 @@ public function splits()
                     false,
                     $this->splits[$featureFlagName]["treatments"],
                     0,
-                    $configs
+                    $configs,
+                    null,
+                    array(),
+                    false
                 );
             }
         }
@@ -92,7 +95,8 @@ public function split($featureFlagName)
                 0,
                 $configs,
                 null,
-                array()
+                array(),
+                false
             );
         }
 

src/SplitIO/Sdk/Manager/SplitManager.php

@@ -68,7 +68,8 @@ private static function parseSplitView($splitRepresentation)
             $split->getChangeNumber(),
             $configs,
             $split->getDefaultTratment(),
-            $split->getSets()
+            $split->getSets(),
+            $split->impressionsDisabled()
         );
     }
 }

src/SplitIO/Sdk/Manager/SplitView.php

@@ -11,6 +11,7 @@
     private $configs;
     private $defaultTreatment;
     private $sets;
+    private $impressionsDisabled;
 
     /**
      * SplitView constructor.
@@ -22,17 +23,19 @@
      * @param $configurations
      * @param $defaultTreatment
      * @param $sets
+     * @param $impressionsDisabled
      */
     public function __construct(
         $name,
         $trafficType,
         $killed,
         $treatments,
         $changeNumber,
         $configs,
         $defaultTreatment,
-        $sets
+        $sets,
+        $impressionsDisabled = false
     ) {
         $this->name = $name;
         $this->trafficType = $trafficType;
         $this->killed = $killed;
@@ -41,6 +44,7 @@
         $this->configs = $configs;
         $this->defaultTreatment = $defaultTreatment;
         $this->sets = $sets;
+        $this->impressionsDisabled = $impressionsDisabled;
     }
 
 
@@ -171,4 +175,20 @@
     {
         return $this->sets;
     }
+
+    /**
+     * @return mixed
+     */
+    public function getImpressionsDisabled()
+    {
+        return $this->impressionsDisabled;
+    }
+
+    /**
+     * @param mixed $impressionsDisabled
+     */
+    public function setImpressionsDisabled($impressionsDisabled)
+    {
+        $this->impressionsDisabled = $impressionsDisabled;
+    }
 }

tests/Suite/Sdk/Helpers/ImpressionsDisabledE2EListener.php

@@ -0,0 +1,30 @@
+<?php
+
+namespace SplitIO\Test\Suite\Sdk\Helpers;
+
+class ImpressionsDisabledE2EListener implements \SplitIO\Sdk\ImpressionListener
+{
+    public $receivedImpressions = array();
+
+    public function logImpression($bundle)
+    {
+        // Bundle is an array with 'impression', 'attributes', 'instance-id', 'sdk-language-version'
+        $impression = $bundle['impression'];
+        $this->receivedImpressions[] = array(
+            'feature' => $impression->getFeature(),
+            'key' => $impression->getId(),
+            'treatment' => $impression->getTreatment(),
+            'label' => $impression->getLabel(),
+            'changeNumber' => $impression->getChangeNumber()
+        );
+    }
+
+    public function close()
+    {
+    }
+
+    public function reset()
+    {
+        $this->receivedImpressions = array();
+    }
+}

tests/Suite/Sdk/Helpers/ImpressionsDisabledListener.php

@@ -0,0 +1,24 @@
+<?php
+
+namespace SplitIO\Test\Suite\Sdk\Helpers;
+
+class ImpressionsDisabledListener implements \SplitIO\Sdk\ImpressionListener
+{
+    public $receivedImpressions = array();
+    public $receivedAttributes = array();
+
+    public function logImpression($impression)
+    {
+        $this->receivedImpressions[] = $impression;
+    }
+
+    public function close()
+    {
+    }
+
+    public function reset()
+    {
+        $this->receivedImpressions = array();
+        $this->receivedAttributes = array();
+    }
+}