From ec3c7a3e58757a23afbb494b5fd9f1a1081fa495 Mon Sep 17 00:00:00 2001
From: Yangster <yanglu@google.com>
Date: Wed, 9 May 2018 15:51:07 -0700
Subject: [PATCH] Add a sampling method to pull gauge when condition changes to
 true.

Test: statsd test

BUG: b/79490890
Change-Id: I82ed6681151f8a217e74bd0d855f817b4fa0619c
---
 cmds/statsd/src/metrics/GaugeMetricProducer.cpp | 6 +++++-
 cmds/statsd/src/statsd_config.proto             | 1 +
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/cmds/statsd/src/metrics/GaugeMetricProducer.cpp b/cmds/statsd/src/metrics/GaugeMetricProducer.cpp
index a940d58b7c4d3..06d8bcd21ef11 100644
--- a/cmds/statsd/src/metrics/GaugeMetricProducer.cpp
+++ b/cmds/statsd/src/metrics/GaugeMetricProducer.cpp
@@ -324,6 +324,10 @@ void GaugeMetricProducer::pullLocked(const int64_t timestampNs) {
             triggerPuller = true;
             break;
         }
+        case GaugeMetric::CONDITION_CHANGE_TO_TRUE: {
+            triggerPuller = mCondition;
+            break;
+        }
         default:
             break;
     }
@@ -348,7 +352,7 @@ void GaugeMetricProducer::onConditionChangedLocked(const bool conditionMet,
     flushIfNeededLocked(eventTimeNs);
     mCondition = conditionMet;
 
-    if (mPullTagId != -1 && mCondition) {
+    if (mPullTagId != -1) {
         pullLocked(eventTimeNs);
     }  // else: Push mode. No need to proactively pull the gauge data.
 }
diff --git a/cmds/statsd/src/statsd_config.proto b/cmds/statsd/src/statsd_config.proto
index fd365602427d3..9b5d72bf56dce 100644
--- a/cmds/statsd/src/statsd_config.proto
+++ b/cmds/statsd/src/statsd_config.proto
@@ -234,6 +234,7 @@ message GaugeMetric {
   enum SamplingType {
     RANDOM_ONE_SAMPLE = 1;
     ALL_CONDITION_CHANGES = 2;
+    CONDITION_CHANGE_TO_TRUE = 3;
   }
   optional SamplingType sampling_type = 9 [default = RANDOM_ONE_SAMPLE] ;