Add activity reporting SQL query generation code

This allows us to have a modular view of all tables used in activity reporting, to facilitate generating reports in BigQuery.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=161849007

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

@@ -0,0 +1,64 @@
+  -- 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 regex's over the monthly appengine logs to determine how many
+  -- EPP requests we received for each command.
+
+SELECT
+  tld,
+  activityReportField AS metricName,
+  -- Manual INTEGER cast to work around a BigQuery bug (b/14560012).
+  INTEGER(COUNT(*)) AS count,
+FROM
+  -- Flatten the "tld" column (repeated) so that domain checks for names
+  -- across multiple TLDs are counted towards each checked TLD as though
+  -- there were one copy of this row per TLD (the effect of flattening).
+  FLATTEN((
+    SELECT
+      -- Use some ugly regex hackery to convert JSON list of strings into
+      -- repeated string values, since there's no built-in for this.
+      -- TODO(b/20829992): replace with "JSON.parse()" inside a JS UDF
+      --   once we can use GoogleSQL; example in b/37629674#comment2.
+      -- e.g. JSON:"{"commandType":"check"...,"targetIds":["ais.a.how"],
+      -- "tld":"","tlds":["a.how"],"icannActivityReportField":"srs-dom-check"}
+      REGEXP_EXTRACT(
+        SPLIT(
+          REGEXP_EXTRACT(
+            JSON_EXTRACT(json, '$.tlds'),
+            r'^\[(.*)\]$')),
+        '^"(.*)"$') AS tld,
+      -- TODO(b/XXX): remove rawTlds after June 2017 (see below).
+      JSON_EXTRACT_SCALAR(json, '$.resourceType') AS resourceType,
+      JSON_EXTRACT_SCALAR(json, '$.icannActivityReportField')
+        AS activityReportField,
+    FROM (
+      SELECT
+        -- Extract JSON payload following log signature.
+        REGEXP_EXTRACT(logMessage, r'FLOW-LOG-SIGNATURE-METADATA: (.*)\n?$')
+          AS json,
+      FROM
+        [%MONTHLY_LOGS_DATA_SET%.%MONTHLY_LOGS_TABLE%]
+      WHERE logMessage CONTAINS 'FLOW-LOG-SIGNATURE-METADATA'
+    )
+  ),
+  -- Second argument to flatten (see above).
+  tld)
+-- Exclude cases that can't be tabulated correctly - activity report field
+-- is null/empty, or the TLD is null/empty even though it's a domain flow.
+WHERE
+  activityReportField != '' AND (tld != '' OR resourceType != 'domain')
+GROUP BY tld, metricName
+ORDER BY tld, metricName