Cass data store for promotion metrics

Used in inventory prediction.

r2/r2/models/promo_metrics.py

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+# The contents of this file are subject to the Common Public Attribution
+# License Version 1.0. (the "License"); you may not use this file except in
+# compliance with the License. You may obtain a copy of the License at
+# http://code.reddit.com/LICENSE. The License is based on the Mozilla Public
+# License Version 1.1, but Sections 14 and 15 have been added to cover use of
+# software over a computer network and provide for limited attribution for the
+# Original Developer. In addition, Exhibit A has been modified to be consistent
+# with Exhibit B.
+#
+# Software distributed under the License is distributed on an "AS IS" basis,
+# WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for
+# the specific language governing rights and limitations under the License.
+#
+# The Original Code is reddit.
+#
+# The Original Developer is the Initial Developer.  The Initial Developer of
+# the Original Code is reddit Inc.
+#
+# All portions of the code written by reddit are Copyright (c) 2006-2012 reddit
+# Inc. All Rights Reserved.
+###############################################################################
+
+from r2.lib.db import tdb_cassandra
+from r2.lib.utils import tup
+from r2.models.subreddit import DefaultSR
+
+
+class PromoMetrics(tdb_cassandra.View):
+    '''
+    Cassandra data store for promotion metrics. Used for inventory prediction.
+
+    Usage:
+      # set metric value for many subreddits at once
+      > PromoMetrics.set('min_daily_pageviews.GET_listing',
+                          {'funny': 63432, 'pics': 48829, 'books': 4})
+
+      # get metric value for one subreddit
+      > res = PromoMetrics.get('min_daily_pageviews.GET_listing', 'funny')
+      {'funny': 1234}
+
+      # get metric value for many subreddits
+      > res = PromoMetrics.get('min_daily_pageviews.GET_listing',
+                               ['funny', 'pics'])
+      {'funny':1234, 'pics':4321}
+
+      # get metric values for all subreddits
+      > res = PromoMetrics.get('min_daily_pageviews.GET_listing')
+    '''
+    _use_db = True
+    _value_type = 'int'
+    _fetch_all_columns = True
+
+    @classmethod
+    def get(cls, metric_name, sr_names=None):
+        if isinstance(sr_names, str):
+            sr_names = (sr_names,)
+        metric = cls._byID(metric_name, properties=sr_names)
+        return metric._values()  # might have additional values
+
+    @classmethod
+    def set(cls, metric_name, values_by_sr):
+        if '' in values_by_sr:  # combine front page values
+            fp = DefaultSR.name.lower()
+            values_by_sr[fp] = values_by_sr.get(fp, 0) + values_by_sr['']
+            del(values_by_sr[''])
+        cls._set_values(metric_name, values_by_sr)