[android] resume file source and wait for result to complete resources cache path change

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/storage/FileSource.java

@@ -312,8 +312,7 @@ public class FileSource {
               Context.MODE_PRIVATE).edit();
           editor.putString(MAPBOX_SHARED_PREFERENCE_RESOURCES_CACHE_PATH, path);
           editor.apply();
-          setResourcesCachePath(applicationContext, path);
-          callback.onSuccess(path);
+          internalSetResourcesCachePath(applicationContext, path, callback);
         }
 
         @Override
@@ -326,11 +325,26 @@ public class FileSource {
     }
   }
 
-  private static void setResourcesCachePath(@NonNull Context context, @NonNull String path) {
-    resourcesCachePathLoaderLock.lock();
-    resourcesCachePath = path;
-    resourcesCachePathLoaderLock.unlock();
-    getInstance(context).setResourceCachePath(path);
+  private static void internalSetResourcesCachePath(@NonNull Context context, @NonNull String path,
+                                                    @NonNull final ResourcesCachePathChangeCallback callback) {
+    final FileSource fileSource = getInstance(context);
+    fileSource.setResourceCachePath(path, new ResourcesCachePathChangeCallback() {
+      @Override
+      public void onSuccess(@NonNull String path) {
+        fileSource.deactivate();
+        resourcesCachePathLoaderLock.lock();
+        resourcesCachePath = path;
+        resourcesCachePathLoaderLock.unlock();
+        callback.onSuccess(path);
+      }
+
+      @Override
+      public void onError(@NonNull String message) {
+        fileSource.deactivate();
+        callback.onError(message);
+      }
+    });
+    fileSource.activate();
   }
 
   private static boolean isPathWritable(String path) {
@@ -388,7 +402,7 @@ public class FileSource {
   public native void setResourceTransform(final ResourceTransformCallback callback);
 
   @Keep
-  private native void setResourceCachePath(String path);
+  private native void setResourceCachePath(String path, ResourcesCachePathChangeCallback callback);
 
   @Keep
   private native void initialize(String accessToken, String cachePath, AssetManager assetManager);

platform/android/MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxsdk/testapp/storage/FileSourceStandaloneTest.kt

@@ -1,6 +1,5 @@
 package com.mapbox.mapboxsdk.testapp.storage
 
-import android.os.Handler
 import android.support.test.annotation.UiThreadTest
 import android.support.test.rule.ActivityTestRule
 import android.support.test.runner.AndroidJUnit4
@@ -10,6 +9,7 @@ import org.junit.*
 import org.junit.rules.TestName
 import org.junit.runner.RunWith
 import java.util.concurrent.CountDownLatch
+import java.util.concurrent.TimeUnit
 
 @RunWith(AndroidJUnit4::class)
 class FileSourceStandaloneTest {
@@ -55,21 +55,59 @@ class FileSourceStandaloneTest {
     fileSourceTestUtils.changePath(fileSourceTestUtils.testPath)
     Assert.assertEquals(fileSourceTestUtils.testPath, FileSource.getResourcesCachePath(rule.activity))
 
-    // workaround for https://github.com/mapbox/mapbox-gl-native/issues/14334
-    val latch = CountDownLatch(1)
-    rule.activity.runOnUiThread {
-      fileSource.activate()
-      Handler().postDelayed({
-        fileSource.deactivate()
-        latch.countDown()
-      }, 2000)
-    }
-    latch.await()
-
     fileSourceTestUtils.changePath(fileSourceTestUtils.originalPath)
     Assert.assertEquals(fileSourceTestUtils.originalPath, FileSource.getResourcesCachePath(rule.activity))
   }
 
+  @Test
+  fun overridePathChangeCallTest() {
+    val firstLatch = CountDownLatch(1)
+    val secondLatch = CountDownLatch(1)
+    rule.activity.runOnUiThread {
+      FileSource.setResourcesCachePath(
+        fileSourceTestUtils.testPath,
+        object : FileSource.ResourcesCachePathChangeCallback {
+          override fun onSuccess(path: String) {
+            Assert.assertEquals(fileSourceTestUtils.testPath, path)
+            firstLatch.countDown()
+          }
+
+          override fun onError(message: String) {
+            Assert.fail("First attempt should succeed.")
+          }
+        })
+
+      FileSource.setResourcesCachePath(
+        fileSourceTestUtils.testPath2,
+        object : FileSource.ResourcesCachePathChangeCallback {
+          override fun onSuccess(path: String) {
+            Assert.fail("Second attempt should fail because first one is in progress.")
+          }
+
+          override fun onError(message: String) {
+            Assert.assertEquals("Another resources cache path change is in progress", message)
+            secondLatch.countDown()
+          }
+        })
+    }
+
+    if (!secondLatch.await(5, TimeUnit.SECONDS)) {
+      rule.runOnUiThread {
+        // if we fail to call a callback, the file source is not going to be deactivated
+        fileSource.deactivate()
+      }
+      Assert.fail("Second attempt should fail.")
+    }
+
+    if (!firstLatch.await(5, TimeUnit.SECONDS)) {
+      rule.runOnUiThread {
+        // if we fail to call a callback, the file source is not going to be deactivated
+        fileSource.deactivate()
+      }
+      Assert.fail("First attempt should succeed.")
+    }
+  }
+
   @After
   fun cleanup() {
     fileSourceTestUtils.cleanup()

platform/android/MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxsdk/testapp/storage/FileSourceTestUtils.kt

@@ -10,10 +10,15 @@ import java.util.concurrent.CountDownLatch
 class FileSourceTestUtils(private val activity: Activity) {
   val originalPath = FileSource.getResourcesCachePath(activity)
   val testPath = "$originalPath/test"
+  val testPath2 = "$originalPath/test2"
+
+  private val paths = listOf(testPath, testPath2)
 
   fun setup() {
-    val testFile = File(testPath)
-    testFile.mkdirs()
+    for (path in paths) {
+      val testFile = File(path)
+      testFile.mkdirs()
+    }
   }
 
   @WorkerThread
@@ -22,25 +27,29 @@ class FileSourceTestUtils(private val activity: Activity) {
     if (currentPath != originalPath) {
       changePath(originalPath)
     }
-    val testFile = File(testPath)
-    if (testFile.exists()) {
-      testFile.deleteRecursively()
+
+    for (path in paths) {
+      val testFile = File(path)
+      if (testFile.exists()) {
+        testFile.deleteRecursively()
+      }
     }
   }
 
   @WorkerThread
-  fun changePath(path: String) {
+  fun changePath(requestedPath: String) {
     val latch = CountDownLatch(1)
     activity.runOnUiThread {
       FileSource.setResourcesCachePath(
-        path,
+        requestedPath,
         object : FileSource.ResourcesCachePathChangeCallback {
           override fun onSuccess(path: String) {
+            Assert.assertEquals(requestedPath, path)
             latch.countDown()
           }
 
           override fun onError(message: String) {
-            Assert.fail("Resource path change failed - path: $path, message: $message")
+            Assert.fail("Resource path change failed - path: $requestedPath, message: $message")
           }
         })
     }

platform/android/src/file_source.cpp

@@ -77,10 +77,25 @@ void FileSource::setResourceTransform(jni::JNIEnv& env, const jni::Object<FileSo
     }
 }
 
-void FileSource::setResourceCachePath(jni::JNIEnv& env, const jni::String& path) {
+void FileSource::setResourceCachePath(jni::JNIEnv& env, const jni::String& path,
+                                      const jni::Object<FileSource::ResourcesCachePathChangeCallback>& _callback) {
+    if (pathChangeCallback) {
+        FileSource::ResourcesCachePathChangeCallback::onError(env, _callback, jni::Make<jni::String>(env, "Another resources cache path change is in progress"));
+        return;
+    }
+
     std::string newPath = jni::Make<std::string>(env, path);
     mapbox::sqlite::setTempPath(newPath);
-    fileSource->setResourceCachePath(newPath + DATABASE_FILE);
+
+    auto global = jni::NewGlobal<jni::EnvAttachingDeleter>(env, _callback);
+    pathChangeCallback = std::make_unique<Actor<PathChangeCallback>>(*Scheduler::GetCurrent(),
+            [this, callback = std::make_shared<decltype(global)>(std::move(global)), newPath] {
+                android::UniqueEnv _env = android::AttachEnv();
+                FileSource::ResourcesCachePathChangeCallback::onSuccess(*_env, *callback, jni::Make<jni::String>(*_env, newPath));
+                pathChangeCallback.reset();
+            });
+
+    fileSource->setResourceCachePath(newPath + DATABASE_FILE, pathChangeCallback->self());
 }
 
 void FileSource::resume(jni::JNIEnv&) {
@@ -123,11 +138,32 @@ mbgl::ResourceOptions FileSource::getSharedResourceOptions(jni::JNIEnv& env, con
     return fileSource->resourceOptions.clone();
 }
 
+// FileSource::ResourcesCachePathChangeCallback //
+
+void FileSource::ResourcesCachePathChangeCallback::onSuccess(jni::JNIEnv& env,
+                                                             const jni::Object<FileSource::ResourcesCachePathChangeCallback>& callback,
+                                                             const jni::String& path) {
+    static auto& javaClass = jni::Class<FileSource::ResourcesCachePathChangeCallback>::Singleton(env);
+    static auto method = javaClass.GetMethod<void (jni::String)>(env, "onSuccess");
+
+    callback.Call(env, method, path);
+}
+
+void FileSource::ResourcesCachePathChangeCallback::onError(jni::JNIEnv& env,
+                                                             const jni::Object<FileSource::ResourcesCachePathChangeCallback>& callback,
+                                                             const jni::String& message) {
+    static auto& javaClass = jni::Class<FileSource::ResourcesCachePathChangeCallback>::Singleton(env);
+    static auto method = javaClass.GetMethod<void (jni::String)>(env, "onError");
+
+    callback.Call(env, method, message);
+}
+
 void FileSource::registerNative(jni::JNIEnv& env) {
-    // Ensure the class for ResourceTransformCallback is cached. If it's requested for the
+    // Ensure the classes are cached. If they're requested for the
     // first time on a background thread, Android's class loader heuristics will fail.
     // https://developer.android.com/training/articles/perf-jni#faq_FindClass
     jni::Class<ResourceTransformCallback>::Singleton(env);
+    jni::Class<ResourcesCachePathChangeCallback>::Singleton(env);
 
     static auto& javaClass = jni::Class<FileSource>::Singleton(env);
 

platform/android/src/file_source.hpp

@@ -11,6 +11,7 @@ namespace mbgl {
 
 template <typename T> class Actor;
 class ResourceTransform;
+using mbgl::PathChangeCallback;
 
 namespace android {
 
@@ -28,6 +29,18 @@ public:
         static std::string onURL(jni::JNIEnv&, const jni::Object<FileSource::ResourceTransformCallback>&, int, std::string);
     };
 
+    struct ResourcesCachePathChangeCallback {
+        static constexpr auto Name() { return "com/mapbox/mapboxsdk/storage/FileSource$ResourcesCachePathChangeCallback";}
+
+        static void onSuccess(jni::JNIEnv&,
+                              const jni::Object<FileSource::ResourcesCachePathChangeCallback>&,
+                              const jni::String&);
+
+        static void onError(jni::JNIEnv&,
+                              const jni::Object<FileSource::ResourcesCachePathChangeCallback>&,
+                              const jni::String&);
+    };
+
     FileSource(jni::JNIEnv&, const jni::String&, const jni::String&, const jni::Object<AssetManager>&);
 
     ~FileSource();
@@ -40,7 +53,7 @@ public:
 
     void setResourceTransform(jni::JNIEnv&, const jni::Object<FileSource::ResourceTransformCallback>&);
 
-    void setResourceCachePath(jni::JNIEnv&, const jni::String&);
+    void setResourceCachePath(jni::JNIEnv&, const jni::String&, const jni::Object<FileSource::ResourcesCachePathChangeCallback>&);
 
     void resume(jni::JNIEnv&);
 
@@ -59,6 +72,7 @@ private:
     optional<int> activationCounter;
     mbgl::ResourceOptions resourceOptions;
     std::unique_ptr<Actor<ResourceTransform>> resourceTransform;
+    std::unique_ptr<Actor<PathChangeCallback>> pathChangeCallback;
     std::shared_ptr<mbgl::DefaultFileSource> fileSource;
 };