fix: support jetty 8+, sparkjava 2.5+

dd-java-agent/instrumentation/jetty-8/jetty-8.gradle

@@ -1,9 +1,8 @@
 apply plugin: 'version-scan'
 
 versionScan {
-  group = "javax.servlet"
-  module = 'javax.servlet-api'
-  legacyModule = "servlet-api"
+  group = "org.eclipse.jetty.server"
+  module = 'org.eclipse.jetty.server-Handler'
   versions = "[3.0,)"
   verifyPresent = [
     "javax.servlet.AsyncEvent"   : null,
@@ -27,8 +26,8 @@ dependencies {
   compile deps.autoservice
 
   testCompile project(':dd-java-agent:testing')
-  testCompile group: 'org.eclipse.jetty', name: 'jetty-server', version: '9.4.6.v20170531'
-  testCompile group: 'org.eclipse.jetty', name: 'jetty-servlet', version: '9.4.6.v20170531'
+  testCompile group: 'org.eclipse.jetty', name: 'jetty-server', version: '8.0.0.v20110901'
+  testCompile group: 'org.eclipse.jetty', name: 'jetty-servlet', version: '8.0.0.v20110901'
 
   testCompile project(':dd-java-agent:instrumentation:okhttp-3') // used in the tests
   testCompile group: 'com.squareup.okhttp3', name: 'okhttp', version: '3.6.0'

dd-java-agent/instrumentation/jetty-8/src/main/java/datadog/trace/instrumentation/jetty8/HandlerInstrumentation.java

@@ -1,4 +1,4 @@
-package datadog.trace.instrumentation.jetty9;
+package datadog.trace.instrumentation.jetty8;
 
 import static datadog.trace.agent.tooling.ClassLoaderMatcher.classLoaderHasClasses;
 import static io.opentracing.log.Fields.ERROR_OBJECT;
@@ -33,7 +33,12 @@ public final class HandlerInstrumentation extends Instrumenter.Configurable {
   public static final String SERVLET_OPERATION_NAME = "jetty.request";
 
   public HandlerInstrumentation() {
-    super("jetty", "jetty-9");
+    super("jetty", "jetty-8");
+  }
+
+  @Override
+  public boolean defaultEnabled() {
+    return false;
   }
 
   @Override
@@ -69,6 +74,10 @@ public final class HandlerInstrumentation extends Instrumenter.Configurable {
     @Advice.OnMethodEnter(suppress = Throwable.class)
     public static Scope startSpan(
         @Advice.Argument(0) final String target, @Advice.Argument(2) final HttpServletRequest req) {
+      if (GlobalTracer.get().activeSpan() != null) {
+        // Tracing might already be applied.  If so ignore this.
+        return null;
+      }
 
       final SpanContext extractedContext =
           GlobalTracer.get()

dd-java-agent/instrumentation/sparkjava-2.5/sparkjava-2.5.gradle

@@ -1,6 +1,6 @@
 apply from: "${rootDir}/gradle/java.gradle"
 
-if (JavaVersion.isJava8Compatible()) {
+if (JavaVersion.current().isJava8Compatible()) {
   sourceSets {
     test {
       groovy {
@@ -12,22 +12,16 @@ if (JavaVersion.isJava8Compatible()) {
 }
 
 dependencies {
-  compileOnly group: 'javax.servlet', name: 'javax.servlet-api', version: '3.1.0'
-  compile('io.opentracing.contrib:opentracing-web-servlet-filter:0.1.0') {
-    transitive = false
-  }
-
   compile project(':dd-java-agent:agent-tooling')
 
   compile deps.bytebuddy
   compile deps.opentracing
   compile deps.autoservice
-  compile group: 'com.sparkjava', name: 'spark-core', version: '2.7.1'
+  compile group: 'com.sparkjava', name: 'spark-core', version: '2.5'
 
+  testCompile project(':dd-java-agent:instrumentation:jetty-8')
   testCompile project(':dd-java-agent:testing')
 
-  // Uses jetty-9 instrumentation for requests
-  testCompile project(':dd-java-agent:instrumentation:jetty-9')
   testCompile group: 'com.squareup.okhttp3', name: 'okhttp', version: '3.6.0'
 
 }

settings.gradle

@@ -21,7 +21,7 @@ include ':dd-java-agent:instrumentation:java-concurrent:akka-testing'
 include ':dd-java-agent:instrumentation:jboss-classloading'
 include ':dd-java-agent:instrumentation:jdbc'
 include ':dd-java-agent:instrumentation:jedis-1.4'
-include ':dd-java-agent:instrumentation:jetty-9'
+include ':dd-java-agent:instrumentation:jetty-8'
 include ':dd-java-agent:instrumentation:jms-1'
 include ':dd-java-agent:instrumentation:jms-2'
 include ':dd-java-agent:instrumentation:kafka-clients-0.11'
@@ -35,7 +35,7 @@ include ':dd-java-agent:instrumentation:play-2.4:play-2.6-testing'
 include ':dd-java-agent:instrumentation:ratpack-1.4'
 include ':dd-java-agent:instrumentation:servlet-2'
 include ':dd-java-agent:instrumentation:servlet-3'
-include ':dd-java-agent:instrumentation:sparkjava-2.7'
+include ':dd-java-agent:instrumentation:sparkjava-2.5'
 include ':dd-java-agent:instrumentation:spring-web'
 include ':dd-java-agent:instrumentation:trace-annotation'