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/icann/sql/transaction_counts.sql

@@ -0,0 +1,76 @@
+#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.
+
+  -- Counts the number of mutating transactions each registrar made.
+
+  -- We populate the fields through explicit logging of
+  -- DomainTransactionRecords, which contain all necessary information for
+  -- reporting (such as reporting time, report field, report amount, etc.
+
+  -- A special note on transfers: we only record 'TRANSFER_SUCCESSFUL' or
+  -- 'TRANSFER_NACKED', and we can infer the gaining and losing parties
+  -- from the enclosing HistoryEntry's clientId and otherClientId
+  -- respectively. This query templates the client ID, field for transfer
+  -- success, field for transfer nacks and default field. This allows us to
+  -- create one query for TRANSFER_GAINING and the other report fields,
+  -- and one query for TRANSFER_LOSING fields from the same template.
+
+-- This outer select just converts the registrar's clientId to their name.
+SELECT
+  tld,
+  registrar_table.registrarName AS registrar_name,
+  metricName,
+  metricValue
+FROM (
+  SELECT
+    tld,
+    clientId,
+    CASE
+      WHEN field = 'TRANSFER_SUCCESSFUL' THEN '%TRANSFER_SUCCESS_FIELD%'
+      WHEN field = 'TRANSFER_NACKED' THEN '%TRANSFER_NACKED_FIELD%'
+      ELSE %DEFAULT_FIELD%
+    END AS metricName,
+    SUM(amount) AS metricValue
+  FROM (
+    SELECT
+      entries.%CLIENT_ID% AS clientId,
+      entries.domainTransactionRecords.tld[SAFE_OFFSET(index)] AS tld,
+      entries.domainTransactionRecords.reportingTime[SAFE_OFFSET(index)]
+          AS reportingTime,
+      entries.domainTransactionRecords.reportField[SAFE_OFFSET(index)]
+          AS field,
+      entries.domainTransactionRecords.reportAmount[SAFE_OFFSET(index)]
+          AS amount
+    FROM
+      `%PROJECT_ID%.%DATASTORE_EXPORT_DATA_SET%.%HISTORYENTRY_TABLE%`
+          AS entries,
+      -- This allows us to 'loop' through the arrays in parallel by index
+      UNNEST(GENERATE_ARRAY(0, ARRAY_LENGTH(
+        entries.domainTransactionRecords.tld) - 1)) AS index
+    -- Ignore null entries
+    WHERE entries.domainTransactionRecords IS NOT NULL )
+  -- Only look at this month's data
+  WHERE reportingTime
+  BETWEEN TIMESTAMP('%EARLIEST_REPORT_TIME%')
+  AND TIMESTAMP('%LATEST_REPORT_TIME%')
+  GROUP BY
+    tld,
+    clientId,
+    field ) AS counts_table
+JOIN
+  `%PROJECT_ID%.%DATASTORE_EXPORT_DATA_SET%.%REGISTRAR_TABLE%`
+      AS registrar_table
+ON
+  counts_table.clientId = registrar_table.__key__.name