fix: Make the StorageOption returned by LocalStorageHelper.getOptions() serializable (#606)

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Fixes #605 ☕️

Author: jianglai

java-storage-nio/google-cloud-nio/src/main/java/com/google/cloud/storage/contrib/nio/testing/LocalStorageHelper.java

@@ -16,9 +16,9 @@
 
 package com.google.cloud.storage.contrib.nio.testing;
 
+import com.google.cloud.ServiceRpc;
 import com.google.cloud.spi.ServiceRpcFactory;
 import com.google.cloud.storage.StorageOptions;
-import com.google.cloud.storage.spi.v1.StorageRpc;
 
 /**
  * Utility to create an in-memory storage configuration for testing. Storage options can be obtained
@@ -71,13 +71,7 @@ public static StorageOptions getOptions() {
     instance.reset();
     return StorageOptions.newBuilder()
         .setProjectId("fake-project-for-testing")
-        .setServiceRpcFactory(
-            new ServiceRpcFactory<StorageOptions>() {
-              @Override
-              public StorageRpc create(StorageOptions options) {
-                return instance;
-              }
-            })
+        .setServiceRpcFactory(new FakeStorageRpcFactory())
         .build();
   }
 
@@ -88,13 +82,25 @@ public StorageRpc create(StorageOptions options) {
   public static StorageOptions customOptions(final boolean throwIfOptions) {
     return StorageOptions.newBuilder()
         .setProjectId("fake-project-for-testing")
-        .setServiceRpcFactory(
-            new ServiceRpcFactory<StorageOptions>() {
-              @Override
-              public StorageRpc create(StorageOptions options) {
-                return new FakeStorageRpc(throwIfOptions);
-              }
-            })
+        .setServiceRpcFactory(new FakeStorageRpcFactory(new FakeStorageRpc(throwIfOptions)))
         .build();
   }
+
+  public static class FakeStorageRpcFactory implements ServiceRpcFactory<StorageOptions> {
+
+    private final FakeStorageRpc instance;
+
+    public FakeStorageRpcFactory() {
+      this(LocalStorageHelper.instance);
+    }
+
+    public FakeStorageRpcFactory(FakeStorageRpc instance) {
+      this.instance = instance;
+    }
+
+    @Override
+    public ServiceRpc create(StorageOptions storageOptions) {
+      return instance;
+    }
+  }
 }

java-storage-nio/google-cloud-nio/src/test/java/com/google/cloud/storage/contrib/nio/testing/LocalStorageHelperTest.java

@@ -23,8 +23,13 @@
 import com.google.cloud.storage.BlobId;
 import com.google.cloud.storage.BlobInfo;
 import com.google.cloud.storage.Storage;
+import com.google.cloud.storage.StorageOptions;
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
 import java.io.File;
 import java.io.IOException;
+import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
 import java.nio.ByteBuffer;
 import java.nio.file.Files;
 import org.junit.After;
@@ -117,4 +122,38 @@ public void testCreateNewFileSetsUpdateTime() {
 
     assertThat(obj.getUpdateTime()).isNotNull();
   }
+
+  @Test
+  public void testStorageOptionIsSerializable() throws Exception {
+    StorageOptions storageOptions = LocalStorageHelper.getOptions();
+    byte[] bytes;
+    try (ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        ObjectOutputStream oos = new ObjectOutputStream(baos)) {
+      oos.writeObject(storageOptions);
+      oos.flush();
+      oos.close();
+      bytes = baos.toByteArray();
+    }
+    try (ByteArrayInputStream bais = new ByteArrayInputStream(bytes);
+        ObjectInputStream ois = new ObjectInputStream(bais)) {
+      assertThat(ois.readObject()).isEqualTo(storageOptions);
+    }
+  }
+
+  @Test
+  public void testStorageOptionIsSerializable_customOptions() throws Exception {
+    StorageOptions storageOptions = LocalStorageHelper.customOptions(false);
+    byte[] bytes;
+    try (ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        ObjectOutputStream oos = new ObjectOutputStream(baos)) {
+      oos.writeObject(storageOptions);
+      oos.flush();
+      oos.close();
+      bytes = baos.toByteArray();
+    }
+    try (ByteArrayInputStream bais = new ByteArrayInputStream(bytes);
+        ObjectInputStream ois = new ObjectInputStream(bais)) {
+      assertThat(ois.readObject()).isEqualTo(storageOptions);
+    }
+  }
 }