tidy listener api on FlagsClient

Author: typotter

features/dd-sdk-android-flags/src/main/kotlin/com/datadog/android/flags/FlagsClient.kt

@@ -16,7 +16,7 @@ import com.datadog.android.core.InternalSdkCore
 import com.datadog.android.flags.internal.DatadogFlagsClient
 import com.datadog.android.flags.internal.DefaultRumEvaluationLogger
 import com.datadog.android.flags.internal.FlagsFeature
-import com.datadog.android.flags.internal.FlagsStateChannel
+import com.datadog.android.flags.internal.FlagsStateManager
 import com.datadog.android.flags.internal.LogWithPolicy
 import com.datadog.android.flags.internal.NoOpFlagsClient
 import com.datadog.android.flags.internal.NoOpRumEvaluationLogger
@@ -28,7 +28,6 @@ import com.datadog.android.flags.internal.repository.DefaultFlagsRepository
 import com.datadog.android.flags.internal.repository.NoOpFlagsRepository
 import com.datadog.android.flags.internal.repository.net.PrecomputeMapper
 import com.datadog.android.flags.model.EvaluationContext
-import com.datadog.android.flags.model.FlagsClientState
 import com.datadog.android.flags.model.ResolutionDetails
 import com.datadog.android.internal.utils.DDCoreSubscription
 import org.json.JSONObject
@@ -151,21 +150,12 @@ interface FlagsClient {
      */
     fun <T : Any> resolve(flagKey: String, defaultValue: T): ResolutionDetails<T>
 
-    /**
-     * Gets the current state of this [FlagsClient].
-     *
-     * The state indicates whether the client is ready to evaluate flags, currently loading
-     * new flag values, or in an error state.
-     *
-     * @return The current [FlagsClientState].
-     */
-    fun getCurrentState(): FlagsClientState
-
     /**
      * Registers a listener to receive state change notifications.
      *
-     * The listener will be notified whenever the client's state changes (e.g., from NOT_READY
-     * to READY, or from READY to RECONCILING when the evaluation context changes).
+     * The listener will be notified whenever the client's state changes (e.g., from
+     * [FlagsClientState.NotReady] to [FlagsClientState.Ready], or from [FlagsClientState.Ready]
+     * to [FlagsClientState.Reconciling] when the evaluation context changes).
      *
      * @param listener The [FlagsStateListener] to register.
      */
@@ -432,8 +422,9 @@ interface FlagsClient {
 
                 val precomputeMapper = PrecomputeMapper(featureSdkCore.internalLogger)
 
-                val flagStateChannel = FlagsStateChannel(
-                    subscription = DDCoreSubscription.create()
+                val flagStateManager = FlagsStateManager(
+                    subscription = DDCoreSubscription.create(),
+                    executorService = executorService
                 )
 
                 val evaluationsManager = EvaluationsManager(
@@ -442,7 +433,7 @@ interface FlagsClient {
                     flagsRepository = flagsRepository,
                     assignmentsReader = assignmentsDownloader,
                     precomputeMapper = precomputeMapper,
-                    flagStateChannel = flagStateChannel
+                    flagStateManager = flagStateManager
                 )
 
                 val rumEvaluationLogger = createRumEvaluationLogger(featureSdkCore)
@@ -454,7 +445,7 @@ interface FlagsClient {
                     flagsConfiguration = configuration,
                     rumEvaluationLogger = rumEvaluationLogger,
                     processor = flagsFeature.processor,
-                    flagStateChannel = flagStateChannel
+                    flagStateManager = flagStateManager
                 )
             }
         }

features/dd-sdk-android-flags/src/main/kotlin/com/datadog/android/flags/internal/DatadogFlagsClient.kt

@@ -16,11 +16,9 @@ import com.datadog.android.flags.internal.model.PrecomputedFlag
 import com.datadog.android.flags.internal.repository.FlagsRepository
 import com.datadog.android.flags.model.ErrorCode
 import com.datadog.android.flags.model.EvaluationContext
-import com.datadog.android.flags.model.FlagsClientState
 import com.datadog.android.flags.model.ResolutionDetails
 import com.datadog.android.flags.model.ResolutionReason
 import org.json.JSONObject
-import java.util.concurrent.atomic.AtomicReference
 
 /**
  * Production implementation of [FlagsClient] that integrates with Datadog's flag evaluation system.
@@ -38,7 +36,7 @@ import java.util.concurrent.atomic.AtomicReference
  * @param flagsConfiguration configuration for the flags feature
  * @param rumEvaluationLogger responsible for sending flag evaluations to RUM.
  * @param processor responsible for writing exposure batches to be sent to flags backend.
- * @param flagStateChannel channel for managing state change listeners
+ * @param flagStateManager channel for managing state change listeners
  */
 @Suppress("TooManyFunctions") // All functions are necessary for flag evaluation lifecycle
 internal class DatadogFlagsClient(
@@ -48,38 +46,8 @@ internal class DatadogFlagsClient(
     private val flagsConfiguration: FlagsConfiguration,
     private val rumEvaluationLogger: RumEvaluationLogger,
     private val processor: EventsProcessor,
-    private val flagStateChannel: FlagsStateChannel
+    private val flagStateManager: FlagsStateManager
 ) : FlagsClient {
-
-    // region State Management
-
-    /**
-     * The current state of this client.
-     * Thread-safe: uses atomic reference for lock-free reads and updates.
-     */
-    private val currentState = AtomicReference(FlagsClientState.NOT_READY)
-
-    /**
-     * Updates the client state and notifies all registered listeners.
-     *
-     * This method is thread-safe and guarantees that listeners receive state changes in order.
-     * The notification is delegated to [flagStateChannel] which handles synchronization.
-     *
-     * @param newState The new state to transition to.
-     * @param error Optional error that caused the state change.
-     */
-    internal fun updateState(newState: FlagsClientState, error: Throwable? = null) {
-        currentState.set(newState)
-        when (newState) {
-            FlagsClientState.NOT_READY -> flagStateChannel.notifyNotReady()
-            FlagsClientState.READY -> flagStateChannel.notifyReady()
-            FlagsClientState.RECONCILING -> flagStateChannel.notifyReconciling()
-            FlagsClientState.ERROR -> flagStateChannel.notifyError(error)
-        }
-    }
-
-    // endregion
-
     // region FlagsClient
 
     /**
@@ -184,14 +152,12 @@ internal class DatadogFlagsClient(
         }
     }
 
-    override fun getCurrentState(): FlagsClientState = currentState.get()
-
     override fun addStateListener(listener: FlagsStateListener) {
-        flagStateChannel.addListener(listener)
+        flagStateManager.addListener(listener)
     }
 
     override fun removeStateListener(listener: FlagsStateListener) {
-        flagStateChannel.removeListener(listener)
+        flagStateManager.removeListener(listener)
     }
 
     // endregion