Introduce support for slim Jenkinsfile Runner packages (#449)

* Save progress

* Get working classloading for slim packaging

* Add Slim packaging POM

* Update filters so that Winstone is retained

* Add Pipeline as YAML to CWP demo

* Update more CWP dependencies to get a stable image

* Update Plugin Installation Manager from 2.2.0 to 2.5.0

.dockerignore

@@ -10,15 +10,17 @@ payload/target
 payload-dependencies/target
 setup/target
 target/
-vanilla-package/target/war
-vanilla-package/target/plugins
+#vanilla-package/target/war
+#vanilla-package/target/plugins
 vanilla-package/target/maven-archiver
 vanilla-package/target/maven-status
 vanilla-package/target/jenkinsfile-runner*
 vanilla-package/target/surefire-reports
 vanilla-package/target/classes
 vanilla-package/target/generated-sources
 vanilla-package/target/generated-test-sources
+packaging-parent-pom/target
+packaging-slim-parent-pom/target
 
 # Tests
 tests

app/pom.xml

@@ -33,6 +33,37 @@
           </execution>
         </executions>
        </plugin>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-dependency-plugin</artifactId>
+        <executions>
+          <execution>
+            <id>prepare-lib</id>
+            <phase>package</phase>
+            <goals>
+              <goal>copy</goal>
+            </goals>
+            <configuration>
+              <artifactItems>
+                <artifactItem>
+                  <groupId>io.jenkins.jenkinsfile-runner</groupId>
+                  <artifactId>setup</artifactId>
+                  <version>${project.version}</version>
+                  <outputDirectory>${project.build.directory}/appassembler/lib/setup</outputDirectory>
+                  <destFileName>setup.jar</destFileName>
+                </artifactItem>
+                <artifactItem>
+                  <groupId>io.jenkins.jenkinsfile-runner</groupId>
+                  <artifactId>payload</artifactId>
+                  <version>${project.version}</version>
+                  <outputDirectory>${project.build.directory}/appassembler/lib/payload</outputDirectory>
+                  <destFileName>payload.jar</destFileName>
+                </artifactItem>
+              </artifactItems>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
       <!-- TODO(oleg_nenashev): Standalone JAR generation works by luck: https://github.com/jenkinsci/jenkinsfile-runner/issues/350
            META-INF definitions are not merged correctly, and extension annotations from the core might be overridden by plugins.
            Custom container description handlers are required to handle META-INF/annotations/hudson.Extension though it might be replaced by META-INF/annotations/hudson.Extension.txt.
@@ -89,24 +120,10 @@
       <artifactId>bootstrap</artifactId>
       <version>${project.version}</version>
     </dependency>
-    <dependency>
-      <groupId>io.jenkins.jenkinsfile-runner</groupId>
-      <artifactId>setup</artifactId>
-      <version>${project.version}</version>
-    </dependency>
-    <dependency>
-      <groupId>io.jenkins.jenkinsfile-runner</groupId>
-      <artifactId>payload</artifactId>
-      <version>${project.version}</version>
-    </dependency>
     <dependency>
       <groupId>commons-collections</groupId>
       <artifactId>commons-collections</artifactId>
     </dependency>
-    <dependency>
-      <groupId>org.jenkins-ci</groupId>
-      <artifactId>symbol-annotation</artifactId>
-    </dependency>
     <dependency>
       <groupId>org.jenkins-ci</groupId>
       <artifactId>annotation-indexer</artifactId>

bootstrap/pom.xml

@@ -23,6 +23,10 @@
       <groupId>org.jenkins-ci</groupId>
       <artifactId>version-number</artifactId>
     </dependency>
+    <dependency>
+      <groupId>io.jenkins.lib</groupId>
+      <artifactId>support-log-formatter</artifactId>
+    </dependency>
 
     <dependency>
       <groupId>junit</groupId>
@@ -40,7 +44,7 @@
         <configuration>
           <resources>
             <resource>
-              <directory>${project.build.directory}/../src/main/resources-filtered</directory>
+              <directory>src/main/resources-filtered</directory>
               <filtering>true</filtering>
             </resource>
           </resources>

bootstrap/src/main/java/io/jenkins/jenkinsfile/runner/bootstrap/ClassLoaderBuilder.java

@@ -3,19 +3,19 @@
 import java.io.File;
 import java.io.FileFilter;
 import java.io.IOException;
+import java.net.MalformedURLException;
 import java.net.URL;
 import java.net.URLClassLoader;
 import java.security.AccessController;
 import java.security.PrivilegedAction;
-import java.util.ArrayList;
-import java.util.List;
+import java.util.HashSet;
 
 /**
  * @author Kohsuke Kawaguchi
  */
 public class ClassLoaderBuilder {
     private final ClassLoader parent;
-    private final List<URL> jars = new ArrayList<>();
+    private final HashSet<URL> jars = new HashSet<>(48);
 
     public ClassLoaderBuilder(ClassLoader parent) {
         this.parent = parent;
@@ -24,15 +24,20 @@ public ClassLoaderBuilder(ClassLoader parent) {
     /**
      * Recursively scan a directory to find jars
      */
-    public ClassLoaderBuilder collectJars(File dir, FileFilter filter) throws IOException {
-        File[] children = dir.listFiles();
+    public ClassLoaderBuilder processJars(File dirOrFile, FileFilter filter, JarHandler handler) throws IOException {
+        if (dirOrFile.isFile() && dirOrFile.getName().endsWith(".jar") && filter.accept(dirOrFile) ) {
+            handler.accept(dirOrFile);
+            return this;
+        }
+
+        File[] children = dirOrFile.listFiles();
         if (children!=null) {
             for (File child : children) {
                 if (child.isDirectory()) {
-                    collectJars(child, filter);
+                    processJars(child, filter, handler);
                 } else {
                     if (child.getName().endsWith(".jar") && filter.accept(child)) {
-                        jars.add(child.toURI().toURL());
+                        handler.accept(child);
                     }
                 }
             }
@@ -41,11 +46,19 @@ public ClassLoaderBuilder collectJars(File dir, FileFilter filter) throws IOExce
     }
 
     public ClassLoaderBuilder collectJars(File dir) throws IOException {
-        return collectJars(dir,(File)->true);
+        return processJars(dir, (File)->true, (jar) -> jars.add(jar.toURI().toURL()));
+    }
+
+    public ClassLoaderBuilder excludeJars(File dir) throws IOException {
+        return processJars(dir, (File)->true, (jar) -> jars.remove(jar.toURI().toURL()));
     }
 
     public ClassLoader make() {
         return AccessController.doPrivileged((PrivilegedAction<URLClassLoader>) () -> new URLClassLoader(jars.toArray(
                 new URL[jars.size()]), parent));
     }
+
+    public interface JarHandler {
+        public void accept(File jar) throws MalformedURLException;
+    }
 }

bootstrap/src/main/java/io/jenkins/jenkinsfile/runner/bootstrap/Util.java

@@ -46,6 +46,9 @@ public static String readJenkinsPomProperty(String key) throws IOException {
             return JFR_PROPERTIES.getProperty(key);
         }
         try (InputStream pomProperties = Bootstrap.class.getResourceAsStream("/jfr.properties")) {
+            if (pomProperties == null) {
+                throw new IOException("Cannot find the Jenkinsfile Runner version properties file: /jfr.properties");
+            }
             Properties props = new Properties();
             props.load(pomProperties);
             JFR_PROPERTIES = props;

bootstrap/src/main/java/io/jenkins/jenkinsfile/runner/bootstrap/commands/JenkinsLauncherCommand.java

@@ -163,6 +163,8 @@ private void installPlugin(File pluginsDir, String shortname, String version) th
     public ClassLoader createJenkinsWarClassLoader() throws PrivilegedActionException {
         return AccessController.doPrivileged((PrivilegedExceptionAction<ClassLoader>) () -> new ClassLoaderBuilder(new SideClassLoader(getPlatformClassloader()))
                 .collectJars(new File(getLauncherOptions().warDir, "WEB-INF/lib"))
+                // In this mode we also take Jetty from the Jenkins core
+                .collectJars(new File(getLauncherOptions().warDir, "winstone.jar"))
                 // servlet API needs to be visible to jenkins.war
                 .collectJars(new File(getAppRepo(), "javax/servlet"))
                 .make());
@@ -171,6 +173,10 @@ public ClassLoader createJenkinsWarClassLoader() throws PrivilegedActionExceptio
     public ClassLoader createSetupClassLoader(ClassLoader jenkins) throws IOException {
         return new ClassLoaderBuilder(jenkins)
                 .collectJars(getAppRepo())
+                .collectJars(getSetupJarDir())
+                // Payload should be skipped, otherwise it will be loaded with a wrong classloader when no bundled plugin jars
+                // NOTE: Not relevant for slim JARs
+                .excludeJars(new File(getAppRepo(), "io/jenkins/jenkinsfile-runner/payload"))
                 .make();
     }
 
@@ -181,6 +187,7 @@ public int runJenkinsfileRunnerApp() throws Throwable {
             return  ((IApp) c.newInstance()).run(this);
         }
 
+        // Slim packaging (no bundled WAR or plugins)
         ClassLoader jenkins = createJenkinsWarClassLoader();
         ClassLoader setup = createSetupClassLoader(jenkins);
 
@@ -220,13 +227,45 @@ public boolean hasClass(String className) {
         try  {
             Class.forName(className);
             return true;
-        }  catch (ClassNotFoundException e) {
+        }  catch (ClassNotFoundException | NoClassDefFoundError e) {
             return false;
         }
     }
 
-    // TODO: move elsewhere
+    /**
+     * Location of the app repo packaged by AppAssembler.
+     * Depending on the configuration, it might include full or slim packaging.
+     * @return Path to the app repo
+     */
     public File getAppRepo() {
         return new File(System.getProperty("app.repo"));
     }
+
+    /**
+     * Location of the app repo packaged by AppAssembler.
+     * Depending on the configuration, it might include full or slim packaging.
+     * @return Path to the app repo
+     */
+    public File getLibDirectory() {
+        if (launcherOptions.libPath != null) {
+            return launcherOptions.libPath;
+        }
+        return new File(System.getProperty("app.repo"), "../lib");
+    }
+
+    public File getSetupJarDir() throws IOException {
+        File setupJar = new File(getLibDirectory(), "setup/");
+        if (!setupJar.exists()) {
+            throw new IOException("Setup JAR is missing: " + setupJar);
+        }
+        return setupJar;
+    }
+
+    public File getPayloadJarDir() throws IOException {
+        File payloadJar = new File(getLibDirectory(), "payload/");
+        if (!payloadJar.exists()) {
+            throw new IOException("Payload JAR is missing: " + payloadJar);
+        }
+        return payloadJar;
+    }
 }

bootstrap/src/main/java/io/jenkins/jenkinsfile/runner/bootstrap/commands/JenkinsLauncherOptions.java

@@ -51,13 +51,17 @@ public class JenkinsLauncherOptions {
             description = "Path to a directory containing Groovy Init Hooks to copy into init.groovy.d")
     public File withInitHooks;
 
-    @CheckForNull
     @CommandLine.Option(names = "--skipShutdown",
             description = "Forces Jenkinsfile Runner to skip the shutdown logic. " +
                     "It reduces the instance termination time but may lead to unexpected behavior in plugins " +
                     "which release external resources on clean up synchronous task queues on shutdown.")
     public boolean skipShutdown;
 
+    @CheckForNull
+    @CommandLine.Option(names = "--libPath",
+            description = "When a slim packaging is used, points to the library directory which contains payload.jar and setup.jar files")
+    public File libPath;
+
 
     public String getMirrorURL(String url) {
         if (this.mirror == null || "".equals(this.mirror.trim())) {

bootstrap/src/main/java/io/jenkins/jenkinsfile/runner/bootstrap/util/OptionalClassLoader.java

@@ -0,0 +1,41 @@
+package io.jenkins.jenkinsfile.runner.bootstrap.util;
+
+/**
+ * Classloader, which might be added to the instance post-factum during the execution.
+ * In Jenkinsfile Runner it is used to set the plugin classloader once the Jenkins instance is initialized.
+ */
+public class OptionalClassLoader extends ClassLoader {
+
+    private final ClassLoader parent;
+    private ClassLoader optional;
+
+    public OptionalClassLoader(ClassLoader parent) {
+        this.parent = parent;
+    }
+
+    public void set(ClassLoader optional) {
+        this.optional = optional;
+    }
+
+    @Override
+    public Class<?> loadClass(String name) throws ClassNotFoundException {
+        ClassNotFoundException parentException;
+        try {
+            return parent.loadClass(name);
+        } catch (ClassNotFoundException ex) {
+            parentException = ex;
+        }
+
+        ClassLoader _opt = optional;
+        if (_opt != null) {
+            try {
+                return _opt.loadClass(name);
+            } catch (ClassNotFoundException ex) {
+                ex.addSuppressed(parentException);
+                throw ex;
+            }
+        }
+
+        throw  parentException;
+    }
+}

demo/cwp/packager-config.yml

@@ -23,6 +23,10 @@ war:
   source:
     version: "2.263"
 plugins:
+  - groupId: "org.jenkins-ci.plugins"
+    artifactId: "script-security"
+    source:
+      version: "1.73"
   - groupId: "org.jenkins-ci.plugins.workflow"
     artifactId: "workflow-job"
     source:
@@ -39,6 +43,10 @@ plugins:
     artifactId: "workflow-step-api"
     source:
       version: "2.22"
+  - groupId: "org.jenkins-ci.plugins.workflow"
+    artifactId: "workflow-scm-step"
+    source:
+      version: "2.11"
   - groupId: "org.jenkins-ci.plugins.workflow"
     artifactId: "workflow-support"
     source:
@@ -83,6 +91,14 @@ plugins:
     artifactId: "durable-task"
     source:
       version: "1.34"
+  - groupId: "io.jenkins.plugins"
+    artifactId: "pipeline-as-yaml"
+    source:
+      version: "0.12-rc"
+  - groupId: "io.jenkins.plugins"
+    artifactId: "snakeyaml-api"
+    source:
+      version: "1.26.4"
 systemProperties: {
     jenkins.model.Jenkins.slaveAgentPort: "50000",
     jenkins.model.Jenkins.slaveAgentPortEnforce: "true"}

packaging-slim-parent-pom/README.adoc

@@ -0,0 +1,26 @@
+= Jenkinsfile Runner Packaging POM - Slim Edition (Experimental)
+:toc:
+:toc-placement: preamble
+:toclevels: 3
+
+This is an experimental parent POM for packaging custom Jenkinsfile Runner images.
+It targets slim packaging when Jenkinsfile Runner loads the WAR file and the plugins from external location.
+
+The parent POM prepares the following artifacts in `target`:
+
+* `jenkinsfile-runner.zip` Slim Jenkinsfile Runner bundle ZIP (~1.5MB).
+  This archive needs to be unzipped, there is an executable in `bin/jenkinsfile-runner`
+* `war/jenkins.war` - Jenkins WAR file, based on the `jenkins.version` property.
+  This file needs to be unzipped for consumption in the `-w` option.
+* `plugins` - List of plugins based on the declared dependencies.
+  Parent POM automatically includes the minimum dependencies declared in plugin POM.
+
+== Usage in Docker
+
+See link:../packaging/docker/unix/adoptopenjdk-8-hotspot/Dockerfile-dev-slim[Dockerfile-dev-slim] for example.
+This example also uses additional optimization tricks.
+
+== Status
+
+The packaging tool is under active development,
+and it may be changed in incompatible way.