[android] Add OfflineManager.packDatabase() API

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/offline/OfflineManager.java

@@ -306,6 +306,47 @@ public class OfflineManager {
     });
   }
 
+  /**
+   * Packs the existing database file into a minimal amount of disk space.
+   * <p>
+   * When the operation is complete or encounters an error, the given callback will be
+   * executed on the database thread; it is the responsibility of the SDK bindings
+   * to re-execute a user-provided callback on the main thread.
+   * </p>
+   *
+   * @param callback the callback to be invoked when the database was reset or when the operation erred.
+   */
+  public void packDatabase(@Nullable final FileSourceCallback callback) {
+    fileSource.activate();
+    nativePackDatabase(new FileSourceCallback() {
+      @Override
+      public void onSuccess() {
+        handler.post(new Runnable() {
+          @Override
+          public void run() {
+            fileSource.deactivate();
+            if (callback != null) {
+              callback.onSuccess();
+            }
+          }
+        });
+      }
+
+      @Override
+      public void onError(@NonNull final String message) {
+        handler.post(new Runnable() {
+          @Override
+          public void run() {
+            fileSource.deactivate();
+            if (callback != null) {
+              callback.onError(message);
+            }
+          }
+        });
+      }
+    });
+  }
+
   /**
    * Forces re-validation of the ambient cache.
    * <p>
@@ -648,6 +689,9 @@ public class OfflineManager {
   @Keep
   private native void nativeResetDatabase(@Nullable FileSourceCallback callback);
 
+  @Keep
+  private native void nativePackDatabase(@Nullable FileSourceCallback callback);
+
   @Keep
   private native void nativeInvalidateAmbientCache(@Nullable FileSourceCallback callback);
 

platform/android/MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxsdk/testapp/offline/CacheTest.kt

@@ -85,4 +85,20 @@ class CacheTest {
     }
     countDownLatch.await()
   }
+
+  @Test
+  fun testSetPackDatabase() {
+    rule.activity.runOnUiThread {
+      OfflineManager.getInstance(context).packDatabase(object : OfflineManager.FileSourceCallback {
+        override fun onSuccess() {
+          countDownLatch.countDown()
+        }
+
+        override fun onError(message: String) {
+          Assert.assertNull("onError should not be called", message)
+        }
+      })
+    }
+    countDownLatch.await()
+  }
 }

platform/android/src/offline/offline_manager.cpp

@@ -8,7 +8,6 @@ namespace mbgl {
 namespace android {
 
 // OfflineManager //
-
 OfflineManager::OfflineManager(jni::JNIEnv& env, const jni::Object<FileSource>& jFileSource)
     : fileSource(std::static_pointer_cast<DefaultFileSource>(mbgl::FileSource::getSharedFileSource(FileSource::getSharedResourceOptions(env, jFileSource)))) {}
 
@@ -123,6 +122,26 @@ void OfflineManager::resetDatabase(jni::JNIEnv& env_, const jni::Object<FileSour
     });
 }
 
+void OfflineManager::packDatabase(jni::JNIEnv& env_, const jni::Object<FileSourceCallback>& callback_) {
+    auto globalCallback = jni::NewGlobal<jni::EnvAttachingDeleter>(env_, callback_);
+
+    fileSource->packDatabase(
+        [
+            // Keep a shared ptr to a global reference of the callback so they are not GC'd in the meanwhile
+            callback = std::make_shared<decltype(globalCallback)>(std::move(globalCallback))](
+            std::exception_ptr exception) mutable {
+            // Reattach, the callback comes from a different thread
+            android::UniqueEnv env = android::AttachEnv();
+
+            if (exception) {
+                OfflineManager::FileSourceCallback::onError(
+                    *env, *callback, jni::Make<jni::String>(*env, mbgl::util::toString(exception)));
+            } else {
+                OfflineManager::FileSourceCallback::onSuccess(*env, *callback);
+            }
+        });
+}
+
 void OfflineManager::invalidateAmbientCache(jni::JNIEnv& env_, const jni::Object<FileSourceCallback>& callback_) {
     auto globalCallback = jni::NewGlobal<jni::EnvAttachingDeleter>(env_, callback_);
 
@@ -207,7 +226,10 @@ void OfflineManager::registerNative(jni::JNIEnv& env) {
 
     #define METHOD(MethodPtr, name) jni::MakeNativePeerMethod<decltype(MethodPtr), (MethodPtr)>(name)
 
-    jni::RegisterNativePeer<OfflineManager>( env, javaClass, "nativePtr",
+    jni::RegisterNativePeer<OfflineManager>(
+        env,
+        javaClass,
+        "nativePtr",
         jni::MakePeer<OfflineManager, const jni::Object<FileSource>&>,
         "initialize",
         "finalize",
@@ -216,6 +238,7 @@ void OfflineManager::registerNative(jni::JNIEnv& env) {
         METHOD(&OfflineManager::createOfflineRegion, "createOfflineRegion"),
         METHOD(&OfflineManager::mergeOfflineRegions, "mergeOfflineRegions"),
         METHOD(&OfflineManager::resetDatabase, "nativeResetDatabase"),
+        METHOD(&OfflineManager::packDatabase, "nativePackDatabase"),
         METHOD(&OfflineManager::invalidateAmbientCache, "nativeInvalidateAmbientCache"),
         METHOD(&OfflineManager::clearAmbientCache, "nativeClearAmbientCache"),
         METHOD(&OfflineManager::setMaximumAmbientCacheSize, "nativeSetMaximumAmbientCacheSize"),

platform/android/src/offline/offline_manager.hpp

@@ -95,6 +95,8 @@ public:
 
     void resetDatabase(jni::JNIEnv&, const jni::Object<FileSourceCallback>& callback_);
 
+    void packDatabase(jni::JNIEnv&, const jni::Object<FileSourceCallback>& callback_);
+
     void invalidateAmbientCache(jni::JNIEnv&, const jni::Object<FileSourceCallback>& callback_);
 
     void clearAmbientCache(jni::JNIEnv&, const jni::Object<FileSourceCallback>& callback_);