Process safe deleteRealm and assetFile

CHANGELOG.md

@@ -2,10 +2,16 @@
 
 ## Breaking Changes
 
+* [ObjectServer] `Realm.deleteRealm()` doesn't support synced Realms for now. See issue #5416.
+
 ## Enhancements
 
+* `Realm.deleteRealm()` and `RealmConfiguration.assetFile()` are multi-processes safe now.
+
 ## Bug Fixes
 
+* Fix some potential database corruption caused by deleting the Realm file while a Realm instance are still opened in another process or the sync client thread.
+
 ## Internal
 
 ### Credits

realm/realm-library/src/androidTest/java/io/realm/RealmTests.java

@@ -2301,8 +2301,11 @@ public void run() {
 
         assertTrue(Realm.deleteRealm(configuration));
 
-        // Directory should be empty now.
-        assertEquals(0, tempDir.listFiles().length);
+        assertEquals(1, tempDir.listFiles().length);
+
+        // Lock file should never be deleted
+        File lockFile = new File(configuration.getPath() + ".lock");
+        assertTrue(lockFile.exists());
     }
 
     // Tests that all methods that require a transaction. (ie. any function that mutates Realm data)

realm/realm-library/src/androidTest/java/io/realm/internal/CollectionTests.java

@@ -57,15 +57,13 @@ public class CollectionTests {
 
     private final long[] oneNullTable = new long[] {NativeObject.NULLPTR};
 
-    private RealmConfiguration config;
     private SharedRealm sharedRealm;
     private Table table;
 
     @Before
     public void setUp() {
-        config = configFactory.createConfiguration();
         sharedRealm = getSharedRealm();
-        populateData();
+        populateData(sharedRealm);
     }
 
     @After
@@ -74,6 +72,16 @@ public void tearDown() {
     }
 
     private SharedRealm getSharedRealm() {
+        RealmConfiguration config = configFactory.createConfiguration();
+        return getSharedRealm(config);
+    }
+
+    private SharedRealm getSharedRealmForLooper() {
+        RealmConfiguration config = looperThread.createConfiguration();
+        return getSharedRealm(config);
+    }
+
+    private SharedRealm getSharedRealm(RealmConfiguration config) {
         OsRealmConfig.Builder configBuilder = new OsRealmConfig.Builder(config)
                 .autoUpdateNotification(true);
         SharedRealm sharedRealm = SharedRealm.getInstance(configBuilder);
@@ -87,7 +95,7 @@ private Table getTable(SharedRealm sharedRealm) {
         return sharedRealm.getTable(Table.getTableNameForClass("test_table"));
     }
 
-    private void populateData() {
+    private void populateData(SharedRealm sharedRealm) {
         sharedRealm.beginTransaction();
         table = sharedRealm.createTable(Table.getTableNameForClass("test_table"));
         // Specify the column types and names
@@ -119,12 +127,13 @@ private void populateData() {
         sharedRealm.commitTransaction();
     }
 
-    private void addRowAsync() {
+    private void addRowAsync(final SharedRealm sharedRealm) {
         final CountDownLatch latch = new CountDownLatch(1);
+        final RealmConfiguration configuration = sharedRealm.getConfiguration();
         new Thread(new Runnable() {
             @Override
             public void run() {
-                SharedRealm sharedRealm = getSharedRealm();
+                SharedRealm sharedRealm = getSharedRealm(configuration);
                 addRow(sharedRealm);
                 sharedRealm.close();
                 latch.countDown();
@@ -253,7 +262,8 @@ public void distinct() {
     @Test
     @RunTestInLooperThread
     public void addListener_shouldBeCalledToReturnTheQueryResults() {
-        final SharedRealm sharedRealm = getSharedRealm();
+        final SharedRealm sharedRealm = getSharedRealmForLooper();
+        populateData(sharedRealm);
         Table table = getTable(sharedRealm);
 
         final Collection collection = new Collection(sharedRealm, table.where());
@@ -332,7 +342,7 @@ public void onChange(Collection element) {
             }
         });
 
-        addRowAsync();
+        addRowAsync(sharedRealm);
 
         sharedRealm.waitForChange();
         sharedRealm.refresh();
@@ -342,7 +352,8 @@ public void onChange(Collection element) {
     @Test
     @RunTestInLooperThread
     public void addListener_queryNotReturned() {
-        final SharedRealm sharedRealm = getSharedRealm();
+        final SharedRealm sharedRealm = getSharedRealmForLooper();
+        populateData(sharedRealm);
         Table table = getTable(sharedRealm);
 
         final Collection collection = new Collection(sharedRealm, table.where());
@@ -357,13 +368,14 @@ public void onChange(Collection collection1) {
             }
         });
 
-        addRowAsync();
+        addRowAsync(sharedRealm);
     }
 
     @Test
     @RunTestInLooperThread
     public void addListener_queryReturned() {
-        final SharedRealm sharedRealm = getSharedRealm();
+        final SharedRealm sharedRealm = getSharedRealmForLooper();
+        populateData(sharedRealm);
         Table table = getTable(sharedRealm);
 
         final Collection collection = new Collection(sharedRealm, table.where());
@@ -379,15 +391,16 @@ public void onChange(Collection collection1) {
             }
         });
 
-        addRowAsync();
+        addRowAsync(sharedRealm);
     }
 
     // Local commit will trigger the listener first when beginTransaction gets called then again when transaction
     // committed.
     @Test
     @RunTestInLooperThread
     public void addListener_triggeredByLocalCommit() {
-        final SharedRealm sharedRealm = getSharedRealm();
+        final SharedRealm sharedRealm = getSharedRealmForLooper();
+        populateData(sharedRealm);
         Table table = getTable(sharedRealm);
         final AtomicInteger listenerCounter = new AtomicInteger(0);
 
@@ -468,7 +481,8 @@ public void collectionIterator_invalid_nonLooperThread_byRefresh() {
     @Test
     @RunTestInLooperThread
     public void collectionIterator_invalid_looperThread_byRemoteTransaction() {
-        final SharedRealm sharedRealm = getSharedRealm();
+        final SharedRealm sharedRealm = getSharedRealmForLooper();
+        populateData(sharedRealm);
         Table table = getTable(sharedRealm);
         final Collection collection = new Collection(sharedRealm, table.where());
         final TestIterator iterator = new TestIterator(collection);
@@ -487,7 +501,7 @@ public void onChange(Collection element) {
             }
         });
 
-        addRowAsync();
+        addRowAsync(sharedRealm);
     }
 
     @Test
@@ -522,6 +536,9 @@ public void onChange(Collection element) {
     @Test
     @RunTestInLooperThread
     public void load() {
+        final SharedRealm sharedRealm = getSharedRealmForLooper();
+        looperThread.closeAfterTest(sharedRealm);
+        populateData(sharedRealm);
         final Collection collection = new Collection(sharedRealm, table.where());
         collection.addListener(collection, new RealmChangeListener<Collection>() {
             @Override

realm/realm-library/src/androidTest/java/io/realm/internal/JNIColumnInfoTest.java

@@ -19,6 +19,7 @@
 import android.support.test.InstrumentationRegistry;
 import android.support.test.runner.AndroidJUnit4;
 
+import org.junit.After;
 import org.junit.Before;
 import org.junit.Rule;
 import org.junit.Test;
@@ -39,16 +40,13 @@ public class JNIColumnInfoTest {
     @Rule
     public final TestRealmConfigurationFactory configFactory = new TestRealmConfigurationFactory();
 
-    @SuppressWarnings("FieldCanBeLocal")
-    private RealmConfiguration config;
-    @SuppressWarnings("FieldCanBeLocal")
     private SharedRealm sharedRealm;
     private Table table;
 
     @Before
     public void setUp() {
         Realm.init(InstrumentationRegistry.getInstrumentation().getContext());
-        config = configFactory.createConfiguration();
+        RealmConfiguration config = configFactory.createConfiguration();
         sharedRealm = SharedRealm.getInstance(config);
 
         table = TestHelper.createTable(sharedRealm, "temp", new TestHelper.AdditionalTableSetup() {
@@ -60,6 +58,13 @@ public void execute(Table table) {
         });
     }
 
+    @After
+    public void tearDown() {
+        if (sharedRealm != null) {
+            sharedRealm.close();
+        }
+    }
+
     @Test
     public void shouldGetColumnInformation() {
 

realm/realm-library/src/androidTest/java/io/realm/internal/JNITableTest.java

@@ -19,6 +19,7 @@
 import android.support.test.runner.AndroidJUnit4;
 import android.util.Pair;
 
+import org.junit.After;
 import org.junit.Before;
 import org.junit.Rule;
 import org.junit.Test;
@@ -60,6 +61,13 @@ public void setUp() {
         sharedRealm = SharedRealm.getInstance(config);
     }
 
+    @After
+    public void tearDown() {
+        if (sharedRealm != null)  {
+            sharedRealm.close();
+        }
+    }
+
     @Test
     public void tableToString() {
         Table t = TestHelper.createTable(sharedRealm, "temp", new TestHelper.AdditionalTableSetup() {
@@ -307,10 +315,6 @@ public void execute(Table t) {
     @Test
     public void getName() {
         String TABLE_NAME = "tableName";
-        RealmConfiguration configuration = configFactory.createConfiguration();
-        Realm.deleteRealm(configuration);
-
-        SharedRealm sharedRealm = SharedRealm.getInstance(configuration);
         //noinspection TryFinallyCanBeTryWithResources
         try {
 

realm/realm-library/src/androidTest/java/io/realm/internal/OsObjectStoreTests.java

@@ -0,0 +1,94 @@
+/*
+ * Copyright 2017 Realm Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package io.realm.internal;
+
+import android.support.test.runner.AndroidJUnit4;
+
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.ExpectedException;
+import org.junit.runner.RunWith;
+
+import java.util.concurrent.atomic.AtomicBoolean;
+
+import io.realm.RealmConfiguration;
+import io.realm.rule.TestRealmConfigurationFactory;
+
+import static junit.framework.Assert.assertEquals;
+import static junit.framework.Assert.assertFalse;
+import static junit.framework.Assert.assertTrue;
+import static junit.framework.Assert.fail;
+
+// Tests for OsObjectStore
+@RunWith(AndroidJUnit4.class)
+public class OsObjectStoreTests {
+    @Rule
+    public final TestRealmConfigurationFactory configFactory = new TestRealmConfigurationFactory();
+    @Rule
+    public final ExpectedException thrown = ExpectedException.none();
+
+    @Test
+    public void callWithLock() {
+        RealmConfiguration config = configFactory.createConfiguration();
+
+        // Return false if there are opened SharedRealm instance
+        SharedRealm sharedRealm = SharedRealm.getInstance(config);
+        assertFalse(OsObjectStore.callWithLock(config, new Runnable() {
+            @Override
+            public void run() {
+                fail();
+            }
+        }));
+        sharedRealm.close();
+
+        final AtomicBoolean callbackCalled = new AtomicBoolean(false);
+        assertTrue(OsObjectStore.callWithLock(config, new Runnable() {
+            @Override
+            public void run() {
+                callbackCalled.set(true);
+            }
+        }));
+        assertTrue(callbackCalled.get());
+    }
+
+    // Test if a java exception can be thrown from the callback.
+    @Test
+    public void callWithLock_throwInCallback() {
+        RealmConfiguration config = configFactory.createConfiguration();
+        final RuntimeException exception = new RuntimeException();
+
+        try {
+            OsObjectStore.callWithLock(config, new Runnable() {
+                @Override
+                public void run() {
+                    throw exception;
+                }
+            });
+            fail();
+        } catch (RuntimeException e) {
+            assertEquals(exception, e);
+        }
+
+        // The lock should be released after exception thrown
+        final AtomicBoolean callbackCalled = new AtomicBoolean(false);
+        assertTrue(OsObjectStore.callWithLock(config, new Runnable() {
+            @Override
+            public void run() {
+                callbackCalled.set(true);
+            }
+        }));
+    }
+}