Add database invariant checker []

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=119162082

javatests/com/google/domain/registry/monitoring/whitebox/VerifyEntityIntegrityActionTest.java

@@ -0,0 +1,87 @@
+// Copyright 2016 The Domain Registry Authors. All Rights Reserved.
+//
+// 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 com.google.domain.registry.monitoring.whitebox;
+
+import static com.google.domain.registry.testing.DatastoreHelper.createTld;
+import static com.google.domain.registry.testing.DatastoreHelper.deleteResource;
+import static com.google.domain.registry.testing.DatastoreHelper.persistActiveDomain;
+import static com.google.domain.registry.testing.LogsSubject.assertAboutLogs;
+import static java.util.logging.Level.SEVERE;
+
+import com.google.common.base.Optional;
+import com.google.common.testing.TestLogHandler;
+import com.google.domain.registry.mapreduce.MapreduceRunner;
+import com.google.domain.registry.model.domain.DomainResource;
+import com.google.domain.registry.model.index.ForeignKeyIndex;
+import com.google.domain.registry.testing.FakeResponse;
+import com.google.domain.registry.testing.mapreduce.MapreduceTestCase;
+
+import org.joda.time.DateTime;
+import org.joda.time.DateTimeZone;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+/** Unit tests for {@link VerifyEntityIntegrityAction}. */
+@RunWith(JUnit4.class)
+public class VerifyEntityIntegrityActionTest
+    extends MapreduceTestCase<VerifyEntityIntegrityAction> {
+
+  private TestLogHandler handler;
+
+  @Before
+  public void before() {
+    createTld("tld");
+
+    action = new VerifyEntityIntegrityAction();
+    handler = new TestLogHandler();
+    VerifyEntityIntegrityAction.logger.addHandler(handler);
+    action.mrRunner = new MapreduceRunner(Optional.of(2), Optional.of(2));
+    action.response = new FakeResponse();
+  }
+
+  @After
+  public void after() {
+    VerifyEntityIntegrityAction.logger.removeHandler(handler);
+  }
+
+  private void runMapreduce() throws Exception {
+    action.run();
+    executeTasksUntilEmpty("mapreduce");
+  }
+
+  @Test
+  public void test_singleDomain_noBadInvariants() throws Exception {
+    persistActiveDomain("ninetails.tld");
+    runMapreduce();
+    assertAboutLogs().that(handler).hasNoLogsAtLevel(SEVERE);
+  }
+
+  @Test
+  public void test_singleDomain_missingFki() throws Exception {
+    persistActiveDomain("ninetails.tld");
+    ForeignKeyIndex<DomainResource> fki =
+        ForeignKeyIndex.load(DomainResource.class, "ninetails.tld", DateTime.now(DateTimeZone.UTC));
+    deleteResource(fki);
+    runMapreduce();
+    // TODO(mcilwain): Check for exception message here.
+    assertAboutLogs()
+        .that(handler)
+        .hasLogAtLevelWithMessage(
+            SEVERE, "Integrity error found while checking foreign key contraints");
+  }
+}