XRay Remote Sampler - Preserve previous rule reservoir if rule property has not changed

CHANGELOG.md

@@ -17,6 +17,7 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 
 - AWS SDK span name to be of the format `Service.Operation` in `go.opentelemetry.io/contrib/instrumentation/github.com/aws/aws-sdk-go-v2/otelaws`. (#3582, #3521)
 - Prevent sampler configuration reset from erroneously sampling first span in `go.opentelemetry.io/contrib/samplers/jaegerremote`. (#3603, #3604)
+- AWS XRay Remote Sampling to preserve previous rule if updated rule property has not changed in `go.opentelemetry.io/contrib/samplers/aws/xray`. (#3619, # TBD)
 
 ## [1.16.0-rc.1/0.41.0-rc.1/0.9.0-rc.1] - 2023-03-02
 

samplers/aws/xray/internal/manifest.go

@@ -20,6 +20,7 @@ import (
 	"fmt"
 	"math"
 	"net/url"
+	"reflect"
 	"sort"
 	"strings"
 	"sync"
@@ -183,7 +184,21 @@ func (m *Manifest) updateRules(rules *getSamplingRulesOutput) {
 	// Re-sort to fix matching priorities.
 	tempManifest.sort()
 
+	var currentRuleMap = make(map[string]Rule)
+
 	m.mu.Lock()
+	for _, rule := range m.Rules {
+		currentRuleMap[rule.ruleProperties.RuleName] = rule
+	}
+
+	for i, newRule := range tempManifest.Rules {
+		if curRule, ok := currentRuleMap[newRule.ruleProperties.RuleName]; ok {
+			if reflect.DeepEqual(newRule.ruleProperties, curRule.ruleProperties) {
+				tempManifest.Rules[i] = curRule
+			}
+		}
+	}
+
 	m.Rules = tempManifest.Rules
 	m.refreshedAt = m.clock.now()
 	m.mu.Unlock()