test changes

Author: nhulston

internal/trace/listener.go

@@ -55,6 +55,24 @@ var tracerInitialized = false
 
 // MakeListener initializes a new trace lambda Listener
 func MakeListener(config Config, extensionManager *extension.ExtensionManager) Listener {
+	if config.TracerOptions == nil {
+		config.TracerOptions = []tracer.StartOption{}
+	}
+
+	// Read DD_TRACE_SAMPLING_RULES before initializing tracer
+	if ruleStr := os.Getenv("DD_TRACE_SAMPLING_RULES"); ruleStr != "" {
+		var rules []map[string]interface{}
+		if err := json.Unmarshal([]byte(ruleStr), &rules); err == nil {
+			// Convert environment rules to tracer.SamplingRule
+			for _, rule := range rules {
+				if rate, ok := rule["sample_rate"].(float64); ok {
+					samplingRule := tracer.RateRule(rate)
+					config.TracerOptions = append(config.TracerOptions,
+						tracer.WithSamplingRules([]tracer.SamplingRule{samplingRule}))
+				}
+			}
+		}
+	}
 
 	return Listener{
 		ddTraceEnabled:           config.DDTraceEnabled,
@@ -113,8 +131,6 @@ func (l *Listener) HandlerStarted(ctx context.Context, msg json.RawMessage) cont
 	return ctx
 }
 
-//
-
 // HandlerFinished ends the function execution span and stops the tracer
 func (l *Listener) HandlerFinished(ctx context.Context, err error) {
 	if functionExecutionSpan != nil {