Merge pull request #47 from thehyve/phone-usage-aggregates

Phone usage aggregates

commons/aggregator/phone_usage_aggregator.avsc

@@ -0,0 +1,13 @@
+{
+  "namespace": "org.radarcns.aggregator",
+  "type": "record",
+  "name": "PhoneUsageAggregator",
+  "doc": "Aggregate time and opening events for an app",
+  "fields": [
+    {"name": "packageName", "type": "string", "doc": "package name of the app in use"},
+    {"name": "durationInForeground", "type":"double", "doc":"Total time in milliseconds the app was in the foreground"},
+    {"name": "timesOpen", "type":"int", "doc":"Total amount of times given app was opened in given time-frame"},
+    {"name": "categoryName", "type": ["null", "string"], "doc": "app category as given by the play store, null if a category is not listed or unable to be fetched", "default": null},
+    {"name": "categoryNameFetchTime", "type": ["null", "double"], "doc": "timestamp in UTC when the category was attempted to fetch from the play store (s), null if not fetched", "default": null}
+  ]
+}