Use LocalDatastoreHelper for integration tests.

Author: wsh

appengine/guestbook-cloud-datastore/src/main/java/com/example/guestbook/Persistence.java

@@ -20,14 +20,26 @@
 import com.google.cloud.datastore.DatastoreOptions;
 import com.google.cloud.datastore.KeyFactory;
 
+import java.util.concurrent.atomic.AtomicReference;
+
 //[START all]
 public class Persistence {
+  private static AtomicReference<Datastore> datastore = new AtomicReference<>();
+
   public static Datastore getDatastore() {
-    return DatastoreOptions.builder().projectId("your-project-id-here").build().service();
+    if (datastore.get() == null) {
+      datastore.set(DatastoreOptions.builder().projectId("your-project-id-here").build().service());
+    }
+
+    return datastore.get();
   }
 
   public static KeyFactory getKeyFactory(Class<?> c) {
     return getDatastore().newKeyFactory().kind(c.getSimpleName());
   }
+
+  public static void setDatastore(Datastore datastore) {
+    Persistence.datastore.set(datastore);
+  }
 }
 //[END all]

appengine/guestbook-cloud-datastore/src/test/java/com/example/guestbook/GreetingTest.java

@@ -19,6 +19,8 @@
 import static org.junit.Assert.assertTrue;
 
 import java.util.List;
+
+import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -28,7 +30,7 @@
 public class GreetingTest {
   @Before
   public void setUp() {
-    TestUtils.wipeDatastore();
+    TestUtils.startDatastore();
   }
 
   @Test
@@ -41,4 +43,9 @@ public void testSaveGreeting() throws Exception {
     assertTrue(greetings.size() == 1);
     assertEquals(greeting, greetings.get(0));
   }
+
+  @After
+  public void tearDown() {
+    TestUtils.stopDatastore();
+  }
 }

appengine/guestbook-cloud-datastore/src/test/java/com/example/guestbook/SignGuestbookServletTest.java

@@ -23,6 +23,8 @@
 import java.util.List;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
+
+import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -46,7 +48,7 @@ public void setUp() throws Exception {
     helper.setUp();
 
     signGuestbookServlet = new SignGuestbookServlet();
-    TestUtils.wipeDatastore();
+    TestUtils.startDatastore();
   }
 
   @Test
@@ -63,4 +65,9 @@ public void doPost_userNotLoggedIn() throws Exception {
     assertTrue(greetings.size() == 1);
     assertTrue(greetings.get(0).content.equals(testGreeting));
   }
+
+  @After
+  public void tearDown() {
+    TestUtils.stopDatastore();
+  }
 }

appengine/guestbook-cloud-datastore/src/test/java/com/example/guestbook/TestUtils.java

@@ -6,10 +6,33 @@
 import com.google.cloud.datastore.Key;
 import com.google.cloud.datastore.Query;
 import com.google.cloud.datastore.QueryResults;
+import com.google.cloud.datastore.testing.LocalDatastoreHelper;
 import com.google.common.collect.Lists;
+
+import java.io.IOException;
 import java.util.ArrayList;
 
 public class TestUtils {
+  static LocalDatastoreHelper datastore = LocalDatastoreHelper.create();
+
+  public static void startDatastore() {
+    try {
+      datastore.start();
+      Persistence.setDatastore(datastore.options().service());
+    } catch (IOException | InterruptedException e) {
+      throw new RuntimeException(e);
+    }
+  }
+
+  public static void stopDatastore() {
+    try {
+      datastore.stop();
+      Persistence.setDatastore(null);
+    } catch (IOException | InterruptedException e) {
+      throw new RuntimeException(e);
+    }
+  }
+
   public static void wipeDatastore() {
     Datastore datastore = getDatastore();
     QueryResults<Key> guestbooks = datastore.run(Query.keyQueryBuilder().kind("Greeting").build());