Performance improvements in Jersey by initializing the ApplicationHandler in the filter constructor (absorbed by Lambda) and not in the filter init method

Author: sapessi

aws-serverless-java-container-core/src/main/java/com/amazonaws/serverless/proxy/internal/testutils/Timer.java

@@ -0,0 +1,63 @@
+package com.amazonaws.serverless.proxy.internal.testutils;
+
+
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+
+public final class Timer {
+    private volatile static Map<String, TimerInfo> timers = new LinkedHashMap<>();
+
+    public static void start(String timerName) {
+        timers.put(timerName, new TimerInfo(System.currentTimeMillis()));
+    }
+
+    public static long stop(String timerName) {
+        TimerInfo info = timers.get(timerName);
+        if (info == null) {
+            throw new IllegalArgumentException("Could not find timer " + timerName);
+        }
+
+        long stopTime = System.currentTimeMillis();
+        info.stop(stopTime);
+
+        return stopTime;
+    }
+
+
+    public static Map<String, TimerInfo> getTimers() {
+        return timers;
+    }
+
+    public static TimerInfo getTimer(String timerName) {
+        return timers.get(timerName);
+    }
+
+    private static class TimerInfo {
+        private long startTime;
+        private long stopTime;
+        private long duration;
+
+        public TimerInfo(long start) {
+            startTime = start;
+        }
+
+        public void stop(long stop) {
+            stopTime = stop;
+            duration = stopTime - startTime;
+        }
+
+        public long getStartTime() {
+            return startTime;
+        }
+
+        public long getStopTime() {
+            return stopTime;
+        }
+
+
+        public long getDuration() {
+            return duration;
+        }
+    }
+}

aws-serverless-java-container-jersey/src/main/java/com/amazonaws/serverless/proxy/jersey/JerseyHandlerFilter.java

@@ -1,8 +1,8 @@
 package com.amazonaws.serverless.proxy.jersey;
 
 
-import com.amazonaws.serverless.exceptions.InvalidRequestEventException;
 import com.amazonaws.serverless.proxy.internal.servlet.AwsProxyHttpServletRequest;
+import com.amazonaws.serverless.proxy.internal.testutils.Timer;
 
 import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
 import org.glassfish.jersey.internal.MapPropertiesDelegate;
@@ -49,22 +49,25 @@ public class JerseyHandlerFilter implements Filter, Container {
     private Logger log = LoggerFactory.getLogger(JerseyHandlerFilter.class);
 
     public JerseyHandlerFilter(Application jaxApplication) {
+        Timer.start("JERSEY_FILTER_INIT");
         app = jaxApplication;
+
+        jersey = new ApplicationHandler(app);
+        jersey.onStartup(this);
+        Timer.stop("JERSEY_FILTER_INIT");
     }
 
     @Override
     public void init(FilterConfig filterConfig)
             throws ServletException {
         log.info("Initialize Jersey application handler");
-        jersey = new ApplicationHandler(app);
-        jersey.onStartup(this);
     }
 
 
     @Override
     public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain)
             throws IOException, ServletException {
-        log.debug("Called Jersey filter");
+        Timer.start("JERSEY_FILTER_DOFILTER");
         // we use a latch to make the processing inside Jersey synchronous
         CountDownLatch jerseyLatch = new CountDownLatch(1);
 
@@ -80,7 +83,7 @@ public void doFilter(ServletRequest servletRequest, ServletResponse servletRespo
             log.error("Interrupted while processing request", e);
             throw new InternalServerErrorException(e);
         }
-
+        Timer.stop("JERSEY_FILTER_DOFILTER");
         filterChain.doFilter(servletRequest, servletResponse);
     }
 

aws-serverless-java-container-jersey/src/main/java/com/amazonaws/serverless/proxy/jersey/JerseyLambdaContainerHandler.java

@@ -25,6 +25,7 @@
 import com.amazonaws.serverless.proxy.internal.servlet.AwsProxyHttpServletRequest;
 import com.amazonaws.serverless.proxy.internal.servlet.AwsProxyHttpServletRequestReader;
 import com.amazonaws.serverless.proxy.internal.servlet.AwsProxyHttpServletResponseWriter;
+import com.amazonaws.serverless.proxy.internal.testutils.Timer;
 import com.amazonaws.serverless.proxy.model.AwsProxyRequest;
 import com.amazonaws.serverless.proxy.model.AwsProxyResponse;
 
@@ -120,11 +121,13 @@ public JerseyLambdaContainerHandler(RequestReader<RequestType, AwsProxyHttpServl
                                         SecurityContextWriter<RequestType> securityContextWriter,
                                         ExceptionHandler<ResponseType> exceptionHandler,
                                         Application jaxRsApplication) {
-        super(requestReader, responseWriter, securityContextWriter, exceptionHandler);
 
+        super(requestReader, responseWriter, securityContextWriter, exceptionHandler);
+        Timer.start("JERSEY_START_TIMER");
         this.jaxRsApplication = jaxRsApplication;
         this.initialized = false;
         this.jerseyFilter = new JerseyHandlerFilter(this.jaxRsApplication);
+        Timer.stop("JERSEY_START_TIMER");
     }
 
     //-------------------------------------------------------------
@@ -140,10 +143,12 @@ protected AwsHttpServletResponse getContainerResponse(AwsProxyHttpServletRequest
     protected void handleRequest(AwsProxyHttpServletRequest httpServletRequest, AwsHttpServletResponse httpServletResponse, Context lambdaContext)
             throws Exception {
 
+        Timer.start("JERSEY_HANDLE_REQUEST");
         // this method of the AwsLambdaServletContainerHandler sets the request context
         super.handleRequest(httpServletRequest, httpServletResponse, lambdaContext);
 
         if (!initialized) {
+            Timer.start("JERSEY_INITIALIZATION");
             // call the onStartup event if set to give developers a chance to set filters in the context
             if (startupHandler != null) {
                 startupHandler.onStartup(getServletContext());
@@ -154,10 +159,12 @@ protected void handleRequest(AwsProxyHttpServletRequest httpServletRequest, AwsH
             jerseyFilterReg.addMappingForUrlPatterns(EnumSet.of(DispatcherType.REQUEST), true, "/*");
 
             initialized = true;
+            Timer.stop("JERSEY_INITIALIZATION");
         }
 
         httpServletRequest.setServletContext(getServletContext());
 
         doFilter(httpServletRequest, httpServletResponse, null);
+        Timer.stop("JERSEY_HANDLE_REQUEST");
     }
 }