Refactor ICANN reporting and billing into common package

This moves the default yearMonth logic into a common ReportingModule, rather than the coarse-scoped BackendModule, which may not want the default parameter extraction logic, as well as moving the 'yearMonth' parameter constant to the common package it's used in. This also provides a basis for future consolidation of the ReportingEmailUtils and BillingEmailUtils classes, which have modest overlap.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=183130311

javatests/google/registry/reporting/ReportingModuleTest.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.reporting;
+
+import static com.google.common.truth.Truth.assertThat;
+import static google.registry.testing.JUnitBackports.expectThrows;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+import google.registry.request.HttpException.BadRequestException;
+import google.registry.testing.FakeClock;
+import google.registry.util.Clock;
+import java.util.Optional;
+import javax.servlet.http.HttpServletRequest;
+import org.joda.time.DateTime;
+import org.joda.time.YearMonth;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+/** Unit tests for {@link ReportingModule}. */
+@RunWith(JUnit4.class)
+public class ReportingModuleTest {
+
+  private HttpServletRequest req = mock(HttpServletRequest.class);
+  private Clock clock;
+  @Before
+  public void setUp() {
+    clock = new FakeClock(DateTime.parse("2017-07-01TZ"));
+  }
+
+  @Test
+  public void testEmptyYearMonthParameter_returnsEmptyYearMonthOptional() {
+    when(req.getParameter("yearMonth")).thenReturn("");
+    assertThat(ReportingModule.provideYearMonthOptional(req)).isEqualTo(Optional.empty());
+  }
+
+  @Test
+  public void testInvalidYearMonthParameter_throwsException() {
+    when(req.getParameter("yearMonth")).thenReturn("201705");
+    BadRequestException thrown =
+        expectThrows(
+            BadRequestException.class, () -> ReportingModule.provideYearMonthOptional(req));
+    assertThat(thrown)
+        .hasMessageThat()
+        .contains("yearMonth must be in yyyy-MM format, got 201705 instead");
+  }
+
+  @Test
+  public void testEmptyYearMonth_returnsLastMonth() {
+    assertThat(ReportingModule.provideYearMonth(Optional.empty(), clock))
+        .isEqualTo(new YearMonth(2017, 6));
+  }
+
+  @Test
+  public void testGivenYearMonth_returnsThatMonth() {
+    assertThat(ReportingModule.provideYearMonth(Optional.of(new YearMonth(2017, 5)), clock))
+        .isEqualTo(new YearMonth(2017, 5));
+  }
+
+}