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.

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

java/google/registry/reporting/icann/sql/epp_metrics.sql

@@ -0,0 +1,58 @@
+#standardSQL
+  -- 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.
+
+  -- Query FlowReporter JSON log messages and calculate SRS metrics.
+
+  -- We use ugly regex's over the monthly appengine logs to determine how many
+  -- EPP requests we received for each command. For example:
+  -- {"commandType":"check"...,"targetIds":["ais.a.how"],
+  -- "tld":"","tlds":["a.how"],"icannActivityReportField":"srs-dom-check"}
+
+SELECT
+  -- Remove quotation marks from tld fields.
+  REGEXP_EXTRACT(tld, '^"(.*)"$') AS tld,
+  activityReportField AS metricName,
+  COUNT(*) AS count
+FROM (
+  SELECT
+    -- TODO(b/32486667): Replace with JSON.parse() UDF when available for views
+    SPLIT(
+    REGEXP_EXTRACT(JSON_EXTRACT(json, '$.tlds'), r'^\[(.*)\]$')) AS tlds,
+    JSON_EXTRACT_SCALAR(json,
+      '$.resourceType') AS resourceType,
+    JSON_EXTRACT_SCALAR(json,
+      '$.icannActivityReportField') AS activityReportField
+  FROM (
+    SELECT
+      -- Extract the logged JSON payload.
+      REGEXP_EXTRACT(logMessage, r'FLOW-LOG-SIGNATURE-METADATA: (.*)\n?$')
+      AS json
+    FROM `%PROJECT_ID%.%ICANN_REPORTING_DATA_SET%.%MONTHLY_LOGS_TABLE%` AS logs
+    JOIN
+      UNNEST(logs.logMessage) AS logMessage
+    WHERE
+      STARTS_WITH(logMessage, "%METADATA_LOG_PREFIX%"))) AS regexes
+JOIN
+  -- Unnest the JSON-parsed tlds.
+  UNNEST(regexes.tlds) AS tld
+-- Exclude cases that can't be tabulated correctly, where activityReportField
+-- is null/empty, or TLD is null/empty despite being a domain flow.
+WHERE
+  activityReportField != ''
+  AND (tld != '' OR resourceType != 'domain')
+GROUP BY
+  tld, metricName
+ORDER BY
+  tld, metricName