Defines a build flag for the EntityHandle storage stack code.

Serves as an example for how to add a new build flag for a feature.

PiperOrigin-RevId: 344932610

java/arcs/android/storage/service/BUILD

@@ -28,6 +28,7 @@ arcs_kt_android_library(
         "//java/arcs/core/storage/database",
         "//java/arcs/core/storage/driver:driver_providers",
         "//java/arcs/core/util",
+        "//java/arcs/flags",
         "//third_party/java/androidx/annotation",
         "//third_party/kotlin/kotlinx_atomicfu",
         "//third_party/kotlin/kotlinx_coroutines",

java/arcs/android/storage/service/MuxedStorageChannelImpl.kt

@@ -17,6 +17,8 @@ import arcs.android.storage.decodeStorageServiceMessageProto
 import arcs.android.storage.toProto
 import arcs.core.storage.DirectStoreMuxer
 import arcs.core.storage.UntypedDirectStoreMuxer
+import arcs.flags.BuildFlagDisabledError
+import arcs.flags.BuildFlags
 import kotlinx.coroutines.CoroutineScope
 
 /** Implementation of [IStorageChannel] for communicating with a [DirectStoreMuxer]. */
@@ -25,6 +27,12 @@ class MuxedStorageChannelImpl(
   scope: CoroutineScope,
   private val statisticsSink: BindingContextStatisticsSink
 ) : BaseStorageChannel(scope, statisticsSink) {
+  init {
+    if (!BuildFlags.ENTITY_HANDLE_API) {
+      throw BuildFlagDisabledError("ENTITY_HANDLE_API")
+    }
+  }
+
   override val tag = "MuxedStorageChannel"
 
   override fun sendMessage(encodedMessage: ByteArray, resultCallback: IResultCallback) {

java/arcs/android/storage/service/MuxedStorageServiceImpl.kt

@@ -17,6 +17,8 @@ import arcs.core.storage.DriverFactory
 import arcs.core.storage.StorageKey
 import arcs.core.storage.UntypedDirectStoreMuxer
 import arcs.core.storage.WriteBackProvider
+import arcs.flags.BuildFlagDisabledError
+import arcs.flags.BuildFlags
 import java.util.concurrent.ConcurrentHashMap
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.launch
@@ -31,6 +33,12 @@ class MuxedStorageServiceImpl(
   private val writeBackProvider: WriteBackProvider,
   private val devToolsProxy: DevToolsProxyImpl?
 ) : IMuxedStorageService.Stub() {
+  init {
+    if (!BuildFlags.ENTITY_HANDLE_API) {
+      throw BuildFlagDisabledError("ENTITY_HANDLE_API")
+    }
+  }
+
   // TODO(b/162747024): Replace this with an LruCache so its size doesn't grow unbounded.
   private val directStoreMuxers = ConcurrentHashMap<StorageKey, UntypedDirectStoreMuxer>()
 

java/arcs/sdk/android/storage/service/BUILD

@@ -22,6 +22,7 @@ arcs_kt_android_library(
         "//java/arcs/core/storage/driver:driver_providers",
         "//java/arcs/core/util",
         "//java/arcs/core/util/performance",
+        "//java/arcs/flags",
         "//third_party/java/androidx/annotation",
         "//third_party/java/androidx/work",
         "//third_party/kotlin/kotlinx_atomicfu",

java/arcs/sdk/android/storage/service/StorageService.kt

@@ -52,6 +52,7 @@ import arcs.core.storage.driver.DatabaseDriverProvider
 import arcs.core.util.TaggedLog
 import arcs.core.util.performance.MemoryStats
 import arcs.core.util.performance.PerformanceStatistics
+import arcs.flags.BuildFlags
 import java.io.FileDescriptor
 import java.io.PrintWriter
 import java.util.concurrent.ConcurrentHashMap
@@ -176,9 +177,6 @@ open class StorageService : ResurrectorService() {
       MANAGER_ACTION -> {
         return StorageServiceManager(storesScope, driverFactory, stores)
       }
-      MUXED_STORAGE_SERVICE_ACTION -> {
-        return MuxedStorageServiceImpl(storesScope, driverFactory, writeBackProvider, devToolsProxy)
-      }
       DEVTOOLS_ACTION -> {
         val flags = application?.applicationInfo?.flags ?: 0
         require(flags and ApplicationInfo.FLAG_DEBUGGABLE != 0) {
@@ -191,6 +189,12 @@ open class StorageService : ResurrectorService() {
       }
     }
 
+    if (BuildFlags.ENTITY_HANDLE_API) {
+      if (intent.action == MUXED_STORAGE_SERVICE_ACTION) {
+        return MuxedStorageServiceImpl(storesScope, driverFactory, writeBackProvider, devToolsProxy)
+      }
+    }
+
     // If we got this far, assume we want to bind IStorageService.
 
     val parcelableOptions = requireNotNull(

javatests/arcs/android/storage/service/BUILD

@@ -39,6 +39,7 @@ arcs_kt_android_test_suite(
         "//java/arcs/core/testutil/handles",
         "//java/arcs/core/util",
         "//java/arcs/core/util/testutil",
+        "//java/arcs/flags/testing",
         "//java/arcs/jvm/util",
         "//java/arcs/jvm/util/testutil",
         "//java/arcs/sdk/android/storage",
@@ -47,6 +48,7 @@ arcs_kt_android_test_suite(
         "//third_party/java/junit:junit-android",
         "//third_party/java/robolectric",
         "//third_party/java/truth:truth-android",
+        "//third_party/kotlin/kotlin:kotlin_test",
         "//third_party/kotlin/kotlinx_atomicfu",
         "//third_party/kotlin/kotlinx_coroutines",
         "//third_party/kotlin/kotlinx_coroutines:kotlinx_coroutines_test",

javatests/arcs/android/storage/service/MuxedStorageChannelImplTest.kt

@@ -11,35 +11,47 @@ import arcs.core.storage.MuxedProxyMessage
 import arcs.core.storage.ProxyMessage
 import arcs.core.storage.UntypedDirectStoreMuxer
 import arcs.core.storage.testutil.NoopDirectStoreMuxer
+import arcs.flags.BuildFlagDisabledError
+import arcs.flags.BuildFlags
+import arcs.flags.testing.BuildFlagsRule
 import com.google.common.truth.Truth.assertThat
 import com.nhaarman.mockitokotlin2.eq
 import com.nhaarman.mockitokotlin2.mock
 import com.nhaarman.mockitokotlin2.verify
+import kotlin.test.assertFailsWith
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.ExperimentalCoroutinesApi
 import kotlinx.coroutines.Job
 import kotlinx.coroutines.test.runBlockingTest
 import org.junit.Before
+import org.junit.Rule
 import org.junit.Test
 import org.junit.runner.RunWith
 
 @RunWith(AndroidJUnit4::class)
 @OptIn(ExperimentalCoroutinesApi::class)
 class MuxedStorageChannelImplTest {
-  private val DUMMY_MESSAGE = MuxedProxyMessage<CrdtData, CrdtOperation, Any?>(
-    "thing0",
-    ProxyMessage.SyncRequest(null)
-  )
+
+  @get:Rule
+  val buildFlagsRule = BuildFlagsRule()
 
   private lateinit var messageCallback: IMessageCallback
   private lateinit var resultCallback: FakeResultCallback
 
   @Before
   fun setUp() {
+    BuildFlags.ENTITY_HANDLE_API = true
     messageCallback = mock {}
     resultCallback = FakeResultCallback()
   }
 
+  @Test
+  fun requiresBuildFlag() = runBlockingTest {
+    BuildFlags.ENTITY_HANDLE_API = false
+
+    assertFailsWith<BuildFlagDisabledError> { createChannel(this) }
+  }
+
   @Test
   fun proxiesMessagesFromDirectStoreMuxer() = runBlockingTest {
     var muxedProxyCallback: MuxedProxyCallback<CrdtData, CrdtOperation, Any?>? = null
@@ -156,4 +168,11 @@ class MuxedStorageChannelImplTest {
     assertThat(result).isNull()
     return channel
   }
+
+  companion object {
+    private val DUMMY_MESSAGE = MuxedProxyMessage<CrdtData, CrdtOperation, Any?>(
+      "thing0",
+      ProxyMessage.SyncRequest(null)
+    )
+  }
 }

third_party/java/arcs/flags/flags.bzl

@@ -24,6 +24,16 @@ ARCS_BUILD_FLAGS = [
             "example_feature_1",
         ],
     ),
+    arcs_build_flag(
+        name = "entity_handle_api",
+        desc = "EntityHandle API and supporting code in the storage stack",
+        bug_id = "b/162747024",
+        status = "NOT_READY",
+        stopwords = [
+            "entity.?handle.?api",
+            "muxed.?storage",
+        ],
+    ),
 ]
 
 validate_flag_list(ARCS_BUILD_FLAGS)