Add beam package to open source build

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=178833972

javatests/google/registry/beam/InvoicingUtilsTest.java

@@ -0,0 +1,74 @@
+// Copyright 2017 The Nomulus 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 google.registry.beam;
+
+import static com.google.common.truth.Truth.assertThat;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+import google.registry.testing.TestDataHelper;
+import org.apache.beam.sdk.io.DefaultFilenamePolicy.Params;
+import org.apache.beam.sdk.io.FileBasedSink;
+import org.apache.beam.sdk.options.ValueProvider;
+import org.apache.beam.sdk.options.ValueProvider.StaticValueProvider;
+import org.apache.beam.sdk.transforms.SerializableFunction;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+/** Unit tests for {@link InvoicingUtils}. */
+@RunWith(JUnit4.class)
+public class InvoicingUtilsTest {
+
+  @Test
+  public void testDestinationFunction_generatesProperFileParams() {
+    SerializableFunction<BillingEvent, Params> destinationFunction =
+        InvoicingUtils.makeDestinationFunction("my/directory");
+
+    BillingEvent billingEvent = mock(BillingEvent.class);
+    // We mock BillingEvent to make the test independent of the implementation of toFilename()
+    when(billingEvent.toFilename()).thenReturn("registrar_tld");
+
+    assertThat(destinationFunction.apply(billingEvent))
+        .isEqualTo(
+            new Params()
+                .withShardTemplate("")
+                .withSuffix(".csv")
+                .withBaseFilename(
+                    FileBasedSink.convertToFileResourceIfPossible("my/directory/registrar_tld")));
+  }
+
+  @Test
+  public void testEmptyDestinationParams() {
+    assertThat(InvoicingUtils.makeEmptyDestinationParams("my/directory"))
+        .isEqualTo(
+            new Params()
+                .withBaseFilename(
+                    FileBasedSink.convertToFileResourceIfPossible("my/directory/failed")));
+  }
+
+  /** Asserts that the instantiated sql template matches a golden expected file. */
+  @Test
+  public void testMakeQueryProvider() {
+    ValueProvider<String> queryProvider =
+        InvoicingUtils.makeQueryProvider(StaticValueProvider.of("2017-10"), "my-project-id");
+    assertThat(queryProvider.get()).isEqualTo(loadFile("billing_events_test.sql"));
+  }
+
+  /** Returns a {@link String} from a file in the {@code billing/testdata/} directory. */
+  private static String loadFile(String filename) {
+    return TestDataHelper.loadFile(InvoicingUtilsTest.class, filename);
+  }
+}