From 68b3a96057a8cc93c0406f139b2bf9a91572cff5 Mon Sep 17 00:00:00 2001 From: Diego Date: Sun, 29 Nov 2015 01:30:14 -0300 Subject: + kamon-autoweave: this new module allow attach the AspectJ loadtime weaving agent to a JVM after it has started (you don't need to use -javaagent). This offers extra flexibility but obviously any classes loaded before attachment will not be woven. --- .../src/main/scala/kamon/autoweave/Autoweave.scala | 32 +++++ .../scala/kamon/autoweave/loader/AgentLoader.scala | 155 +++++++++++++++++++++ 2 files changed, 187 insertions(+) create mode 100644 kamon-autoweave/src/main/scala/kamon/autoweave/Autoweave.scala create mode 100644 kamon-autoweave/src/main/scala/kamon/autoweave/loader/AgentLoader.scala (limited to 'kamon-autoweave/src/main/scala/kamon/autoweave') diff --git a/kamon-autoweave/src/main/scala/kamon/autoweave/Autoweave.scala b/kamon-autoweave/src/main/scala/kamon/autoweave/Autoweave.scala new file mode 100644 index 00000000..29c4254a --- /dev/null +++ b/kamon-autoweave/src/main/scala/kamon/autoweave/Autoweave.scala @@ -0,0 +1,32 @@ +/* ========================================================================================= + * Copyright © 2013-2015 the kamon project + * + * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file + * except in compliance with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software distributed under the + * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, + * either express or implied. See the License for the specific language governing permissions + * and limitations under the License. + * ========================================================================================= + */ + +package kamon.autoweave + +import kamon.Kamon +import kamon.autoweave.loader.AgentLoader +import org.aspectj.weaver.loadtime.Agent + + +object Autoweave { + val config = Kamon.config.getConfig("kamon.autowave.options") + val verbose = config.getBoolean("verbose") + val showWeaveInfo = config.getBoolean("showWeaveInfo") + + System.setProperty("aj.weaving.verbose", verbose.toString) + System.setProperty("org.aspectj.weaver.showWeaveInfo", showWeaveInfo.toString) + + AgentLoader.attachAgentToJVM(classOf[Agent]) + } diff --git a/kamon-autoweave/src/main/scala/kamon/autoweave/loader/AgentLoader.scala b/kamon-autoweave/src/main/scala/kamon/autoweave/loader/AgentLoader.scala new file mode 100644 index 00000000..d4efdb85 --- /dev/null +++ b/kamon-autoweave/src/main/scala/kamon/autoweave/loader/AgentLoader.scala @@ -0,0 +1,155 @@ +/* ========================================================================================= + * Copyright © 2013-2015 the kamon project + * + * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file + * except in compliance with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software distributed under the + * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, + * either express or implied. See the License for the specific language governing permissions + * and limitations under the License. + * ========================================================================================= + */ + +package kamon.autoweave.loader + +import java.io.{File, FileOutputStream, InputStream} +import java.lang.management.ManagementFactory +import java.util +import java.util.jar.Attributes.Name +import java.util.jar.{JarEntry, JarOutputStream, Manifest} + +import com.sun.tools.attach.spi.AttachProvider +import com.sun.tools.attach.{VirtualMachine, VirtualMachineDescriptor} +import sun.tools.attach._ + +import scala.util.control.NoStackTrace +import scala.util.{Failure, Success, Try} + +object AgentLoader { + + /** + * Gets the current JVM PID + * + * @return Returns the PID + */ + + private def getPidFromRuntimeMBean: String = { + val jvm = ManagementFactory.getRuntimeMXBean.getName + val pid = jvm.substring(0, jvm.indexOf('@')) + pid + } + + /** + * Loads an agent into a JVM. + * + * @param agent The main agent class. + * @param resources Array of classes to be included with agent. + */ + def attachAgentToJVM(agent: Class[_], resources: Seq[Class[_]] = Seq.empty): Unit = { + val vm = attachToRunningJVM() + vm.loadAgent(generateAgentJar(agent, resources).getAbsolutePath) + vm.detach() + } + + /** + * Java variant + * + * @param agent + */ + def attachAgentToJVM(agent: Class[_]): Unit = attachAgentToJVM(agent, Seq.empty) + + /** + * Generates a temporary agent file to be loaded. + * + * @param agent The main agent class. + * @param resources Array of classes to be included with agent. + * @return Returns a temporary jar file with the specified classes included. + */ + private def generateAgentJar(agent: Class[_], resources: Seq[Class[_]]): File = { + val jarFile = File.createTempFile("agent", ".jar") + jarFile.deleteOnExit() + + val manifest = new Manifest() + val mainAttributes = manifest.getMainAttributes + // Create manifest stating that agent is allowed to transform classes + mainAttributes.put(Name.MANIFEST_VERSION, "1.0") + mainAttributes.put(new Name("Agent-Class"), agent.getName) + mainAttributes.put(new Name("Can-Retransform-Classes"), "true") + mainAttributes.put(new Name("Can-Redefine-Classes"), "true") + + val jos = new JarOutputStream(new FileOutputStream(jarFile), manifest) + + jos.putNextEntry(new JarEntry(agent.getName.replace('.', '/') + ".class")) + + jos.write(getBytesFromStream(agent.getClassLoader.getResourceAsStream(unqualify(agent)))) + jos.closeEntry() + + for (clazz ← resources) { + val name = unqualify(clazz) + jos.putNextEntry(new JarEntry(name)) + jos.write(getBytesFromStream(clazz.getClassLoader.getResourceAsStream(name))) + jos.closeEntry() + } + + jos.close() + jarFile + } + + /** + * Gets bytes from InputStream. + * + * @param stream + * The InputStream. + * @return + * Returns a byte[] representation of given stream. + */ + private def getBytesFromStream(stream: InputStream): Array[Byte] = { + Stream.continually(stream.read).takeWhile(_ != -1).map(_.toByte).toArray + } + + private def unqualify(clazz: Class[_]): String = clazz.getName.replace('.', '/') + ".class" + + /** + * Gets the current HotSpotVirtualMachine implementation otherwise a failure. + * + * @return + * Returns the HotSpotVirtualMachine implementation of the running JVM. + */ + private def findVirtualMachineImplementation(): Try[Class[_ <: HotSpotVirtualMachine]] = System.getProperty("os.name") match { + case os if os.startsWith("Windows") => Success(classOf[WindowsVirtualMachine]) + case os if os.startsWith("Mac OS X") => Success(classOf[BsdVirtualMachine]) + case os if os.startsWith("Solaris") => Success(classOf[SolarisVirtualMachine]) + case os if os.startsWith("Linux") || os.startsWith("LINUX") => Success(classOf[LinuxVirtualMachine]) + case other => Failure(new RuntimeException(s"Cannot use Attach API on unknown OS: $other") with NoStackTrace) + } + + /** + * Attach to the running JVM. + * + * @return + * Returns the attached VirtualMachine + */ + private def attachToRunningJVM(): VirtualMachine = { + val AttachProvider = new AttachProvider() { + override def name(): String = null + override def `type`(): String = null + override def attachVirtualMachine(id: String): VirtualMachine = null + override def listVirtualMachines(): util.List[VirtualMachineDescriptor] = null + } + + findVirtualMachineImplementation() match { + case Success(vmClass) => + val pid = getPidFromRuntimeMBean + // This is only done with Reflection to avoid the JVM pre-loading all the XyzVirtualMachine classes. + val vmConstructor = vmClass.getConstructor(classOf[AttachProvider], classOf[String]) + val newVM = vmConstructor.newInstance(AttachProvider, pid) + newVM.asInstanceOf[VirtualMachine] + case Failure(reason) => throw reason + } + } +} + + -- cgit v1.2.3