fix: logging optimisations to reduce unnecessary logics and inits

Author: Pankaj Agrawal

powertools-core/src/main/java/software/amazon/lambda/powertools/core/internal/LambdaHandlerProcessor.java

@@ -56,19 +56,19 @@ public static boolean placedOnStreamHandler(final ProceedingJoinPoint pjp) {
                 && pjp.getArgs()[2] instanceof Context;
     }
 
-    public static Optional<Context> extractContext(final ProceedingJoinPoint pjp) {
+    public static Context extractContext(final ProceedingJoinPoint pjp) {
 
         if (isHandlerMethod(pjp)) {
             if (placedOnRequestHandler(pjp)) {
-                return of((Context) pjp.getArgs()[1]);
+                return (Context) pjp.getArgs()[1];
             }
 
             if (placedOnStreamHandler(pjp)) {
-                return of((Context) pjp.getArgs()[2]);
+                return (Context) pjp.getArgs()[2];
             }
         }
 
-        return empty();
+        return null;
     }
 
     public static String serviceName() {

powertools-logging/src/main/java/software/amazon/lambda/powertools/logging/LoggingUtils.java

@@ -26,7 +26,7 @@
  * {@see Logging}
  */
 public final class LoggingUtils {
-    private static ObjectMapper objectMapper = new ObjectMapper();
+    private static ObjectMapper objectMapper;
 
     private LoggingUtils() {
     }
@@ -93,6 +93,10 @@ public static void defaultObjectMapper(ObjectMapper objectMapper) {
     }
 
     public static ObjectMapper objectMapper() {
+        if(null == objectMapper) {
+            objectMapper =  new ObjectMapper();
+        }
+
         return objectMapper;
     }
 }

powertools-logging/src/main/java/software/amazon/lambda/powertools/logging/internal/LambdaLoggingAspect.java

@@ -23,6 +23,7 @@
 import java.util.Optional;
 import java.util.Random;
 
+import com.amazonaws.services.lambda.runtime.Context;
 import com.fasterxml.jackson.core.JsonPointer;
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.JsonNode;
@@ -85,12 +86,13 @@ public Object around(ProceedingJoinPoint pjp,
 
         setLogLevelBasedOnSamplingRate(pjp, logging);
 
-        extractContext(pjp)
-                .ifPresent(context -> {
-                    appendKeys(DefaultLambdaFields.values(context));
-                    appendKey("coldStart", isColdStart() ? "true" : "false");
-                    appendKey("service", serviceName());
-                });
+        Context extractContext = extractContext(pjp);
+
+        if(null != extractContext) {
+            appendKeys(DefaultLambdaFields.values(extractContext));
+            appendKey("coldStart", isColdStart() ? "true" : "false");
+            appendKey("service", serviceName());
+        }
 
         getXrayTraceId().ifPresent(xRayTraceId -> appendKey("xray_trace_id", xRayTraceId));
 
@@ -120,9 +122,9 @@ private static void resetLogLevels(Level logLevel) {
 
     private void setLogLevelBasedOnSamplingRate(final ProceedingJoinPoint pjp,
                                                 final Logging logging) {
+        double samplingRate = samplingRate(logging);
+
         if (isHandlerMethod(pjp)) {
-            float sample = SAMPLER.nextFloat();
-            double samplingRate = samplingRate(logging);
 
             if (samplingRate < 0 || samplingRate > 1) {
                 LOG.debug("Skipping sampling rate configuration because of invalid value. Sampling rate: {}", samplingRate);
@@ -131,6 +133,12 @@ private void setLogLevelBasedOnSamplingRate(final ProceedingJoinPoint pjp,
 
             appendKey("samplingRate", String.valueOf(samplingRate));
 
+            if (samplingRate == 0) {
+                return;
+            }
+
+            float sample = SAMPLER.nextFloat();
+
             if (samplingRate > sample) {
                 resetLogLevels(Level.DEBUG);
 

powertools-metrics/src/main/java/software/amazon/lambda/powertools/metrics/internal/LambdaMetricsAspect.java

@@ -2,6 +2,7 @@
 
 import java.lang.reflect.Field;
 
+import com.amazonaws.services.lambda.runtime.Context;
 import org.aspectj.lang.ProceedingJoinPoint;
 import org.aspectj.lang.annotation.Around;
 import org.aspectj.lang.annotation.Aspect;
@@ -53,10 +54,12 @@ public Object around(ProceedingJoinPoint pjp,
 
             logger.setNamespace(namespace(metrics));
 
-            extractContext(pjp).ifPresent((context) -> {
-                coldStartSingleMetricIfApplicable(context.getAwsRequestId(), context.getFunctionName(), metrics);
-                logger.putProperty(REQUEST_ID_PROPERTY, context.getAwsRequestId());
-            });
+            Context extractContext = extractContext(pjp);
+
+            if( null != extractContext) {
+                coldStartSingleMetricIfApplicable(extractContext.getAwsRequestId(), extractContext.getFunctionName(), metrics);
+                logger.putProperty(REQUEST_ID_PROPERTY, extractContext.getAwsRequestId());
+            }
 
             LambdaHandlerProcessor.getXrayTraceId()
                     .ifPresent(traceId -> logger.putProperty(TRACE_ID_PROPERTY, traceId));