From feddb5d52a75f698ee58ce548ccd9cda0b04ad76 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ivar=20Conradi=20=C3=98sthus?= <ivarconr@gmail.com>
Date: Wed, 19 Feb 2025 08:11:28 +0100
Subject: [PATCH] fix: metric bucket start time should be reset everytime it is
 sent (#219)

* fix: metric bucket start time should be reset everytime it is sent

* chore: add test to cover that time is correctly advanced by metrics

---------

Co-authored-by: Simon Hornby <liquidwicked64@gmail.com>
---
 unleash-yggdrasil/src/lib.rs | 27 ++++++++++++++++++++++++++-
 1 file changed, 26 insertions(+), 1 deletion(-)

diff --git a/unleash-yggdrasil/src/lib.rs b/unleash-yggdrasil/src/lib.rs
index d2bbc5e..f809bc8 100644
--- a/unleash-yggdrasil/src/lib.rs
+++ b/unleash-yggdrasil/src/lib.rs
@@ -225,6 +225,7 @@ pub struct EngineState {
     compiled_state: Option<CompiledState>,
     previous_state: ClientFeatures,
     toggle_metrics: DashMap<String, Metric>,
+    toggle_metrics_start: DateTime<Utc>,
     pub started: DateTime<Utc>,
 }
 
@@ -233,6 +234,7 @@ impl Default for EngineState {
         Self {
             compiled_state: Default::default(),
             toggle_metrics: Default::default(),
+            toggle_metrics_start: Utc::now(),
             previous_state: Default::default(),
             started: Utc::now(),
         }
@@ -354,9 +356,11 @@ impl EngineState {
             .collect();
 
         if !metrics.is_empty() {
+            let start = self.toggle_metrics_start;
+            self.toggle_metrics_start = Utc::now();
             Some(MetricBucket {
                 toggles: metrics,
-                start: self.started,
+                start,
                 stop: Utc::now(),
             })
         } else {
@@ -1083,6 +1087,27 @@ mod test {
         assert!(metrics.is_none());
     }
 
+    #[test]
+    pub fn getting_metrics_restarts_time() {
+        let compiled_state = HashMap::new();
+        let mut state = EngineState {
+            compiled_state: Some(compiled_state),
+            ..Default::default()
+        };
+
+        state.count_toggle("some-test-toggle", true);
+
+        let metrics = state.get_metrics().unwrap();
+        let start = metrics.start;
+        std::thread::sleep(std::time::Duration::from_millis(1));
+
+        state.count_toggle("some-test-toggle", true);
+        let metrics = state.get_metrics().unwrap();
+        let new_start = metrics.start;
+
+        assert!(new_start > start);
+    }
+
     #[test]
     pub fn unknown_features_and_variants_get_metrics() {
         let mut compiled_state = HashMap::new();