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

java/google/registry/reporting/ReportingModule.java

@@ -0,0 +1,67 @@
+// 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 google.registry.request.RequestParameters.extractOptionalParameter;
+
+import dagger.Module;
+import dagger.Provides;
+import google.registry.request.HttpException.BadRequestException;
+import google.registry.request.Parameter;
+import google.registry.util.Clock;
+import java.util.Optional;
+import javax.servlet.http.HttpServletRequest;
+import org.joda.time.YearMonth;
+import org.joda.time.format.DateTimeFormat;
+import org.joda.time.format.DateTimeFormatter;
+
+/**
+ * Dagger module for injecting common settings for all Backend tasks.
+ */
+@Module
+public class ReportingModule {
+
+  /**
+   * The request parameter name used by reporting actions that takes a year/month parameter, which
+   * defaults to the last month.
+   */
+  public static final String PARAM_YEAR_MONTH = "yearMonth";
+
+  /** Extracts an optional YearMonth in yyyy-MM format from the request. */
+  @Provides
+  @Parameter(PARAM_YEAR_MONTH)
+  static Optional<YearMonth> provideYearMonthOptional(HttpServletRequest req) {
+    DateTimeFormatter formatter = DateTimeFormat.forPattern("yyyy-MM");
+    Optional<String> optionalYearMonthStr = extractOptionalParameter(req, PARAM_YEAR_MONTH);
+    try {
+      return optionalYearMonthStr.map(s -> YearMonth.parse(s, formatter));
+    } catch (IllegalArgumentException e) {
+      throw new BadRequestException(
+          String.format(
+              "yearMonth must be in yyyy-MM format, got %s instead",
+              optionalYearMonthStr.orElse("UNSPECIFIED YEARMONTH")));
+    }
+  }
+
+  /**
+   * Provides the yearMonth in yyyy-MM format, if not specified in the request, defaults to one
+   * month prior to run time.
+   */
+  @Provides
+  static YearMonth provideYearMonth(
+      @Parameter(PARAM_YEAR_MONTH) Optional<YearMonth> yearMonthOptional, Clock clock) {
+    return yearMonthOptional.orElseGet(() -> new YearMonth(clock.nowUtc().minusMonths(1)));
+  }
+}