[AI-FSSDK] [FSSDK-12262] Exclude CMAB from UserProfileService

Author: jaeopt

lib/optimizely/decision_service.rb

@@ -99,8 +99,15 @@ def get_variation(project_config, experiment_id, user_context, user_profile_trac
       return VariationResult.new(nil, false, decide_reasons, whitelisted_variation_id) if whitelisted_variation_id
 
       should_ignore_user_profile_service = decide_options.include? Optimizely::Decide::OptimizelyDecideOption::IGNORE_USER_PROFILE_SERVICE
-      # Check for saved bucketing decisions if decide_options do not include ignoreUserProfileService
-      unless should_ignore_user_profile_service && user_profile_tracker
+      # CMAB experiments are excluded from UPS (sticky bucketing) because CMAB decisions
+      # are dynamic and should not be persisted across the experiment lifetime.
+      is_cmab_experiment = experiment.key?('cmab') && !experiment['cmab'].nil?
+      if is_cmab_experiment
+        message = "Skipping UPS lookup and save for CMAB experiment '#{experiment_key}'."
+        @logger.log(Logger::INFO, message)
+        decide_reasons.push(message)
+      elsif !(should_ignore_user_profile_service && user_profile_tracker)
+        # Check for saved bucketing decisions if decide_options do not include ignoreUserProfileService
         saved_variation_id, reasons_received = get_saved_variation_id(project_config, experiment_id, user_profile_tracker.user_profile)
         decide_reasons.push(*reasons_received)
         if saved_variation_id
@@ -155,7 +162,8 @@ def get_variation(project_config, experiment_id, user_context, user_profile_trac
       decide_reasons.push(message) if message
 
       # Persist bucketing decision
-      user_profile_tracker.update_user_profile(experiment_id, variation_id) unless should_ignore_user_profile_service && user_profile_tracker
+      # Skip UPS save for CMAB experiments since their decisions are dynamic
+      user_profile_tracker.update_user_profile(experiment_id, variation_id) unless (should_ignore_user_profile_service && user_profile_tracker) || is_cmab_experiment
       VariationResult.new(cmab_uuid, false, decide_reasons, variation_id)
     end