build Spark Monitor plugin into a separate jar

Author: Vincent Ye

README.md

@@ -80,6 +80,59 @@ This results in 2 packages.
 
 NOTE: `make release` uses `docker`. Please refer to `docker` installation instructions for your system.
 
+## Building Individual Components
+
+### Main Toree Assembly
+To build just the main Toree assembly jar (without spark-monitor-plugin):
+```
+sbt assembly
+```
+This creates: `target/scala-2.12/toree-assembly-<VERSION>.jar`
+
+### Spark Monitor Plugin
+To build the spark-monitor-plugin as a separate jar:
+```
+sbt sparkMonitorPlugin/assembly
+```
+This creates: `spark-monitor-plugin/target/scala-2.12/spark-monitor-plugin-<VERSION>.jar`
+
+### Build All Components
+To compile all projects including both the main assembly and spark-monitor-plugin:
+```
+sbt compile
+```
+
+**Note**: The spark-monitor-plugin is now built as a separate jar and is not included in the main Toree assembly.
+
+## Using the Spark Monitor Plugin
+
+To enable the Spark Monitor Plugin in your Toree application, you need to specify the path to the plugin JAR when starting Toree:
+
+### Option 1: Command Line Parameter
+```bash
+# Start Toree with spark-monitor-plugin enabled
+java -jar target/scala-2.12/toree-assembly-<VERSION>.jar --magic-url file:///path/to/spark-monitor-plugin/target/scala-2.12/spark-monitor-plugin-<VERSION>.jar [other-options]
+```
+
+### Option 2: Jupyter Kernel Installation
+When installing Toree as a Jupyter kernel, you can specify the plugin:
+```bash
+jupyter toree install --spark_home=<YOUR_SPARK_PATH> --kernel_name=toree_with_monitor --toree_opts="--magic-url file:///path/to/spark-monitor-plugin-<VERSION>.jar"
+```
+
+### Option 3: Configuration File
+You can also specify the plugin in a configuration file and use the `--profile` option:
+```json
+{
+  "magic_urls": ["file:///path/to/spark-monitor-plugin-<VERSION>.jar"]
+}
+```
+Then start with: `java -jar toree-assembly.jar --profile config.json`
+
+**Important**:
+- Make sure to use the absolute path to the spark-monitor-plugin JAR file and ensure the JAR is accessible from the location where Toree is running.
+- The JAR file name does not contain "toree" prefix to avoid automatic loading as an internal plugin. This allows you to control when the SparkMonitorPlugin is enabled via the `--magic-url` parameter.
+
 Run Examples
 ============
 To play with the example notebooks, run

build.sbt

@@ -123,7 +123,7 @@ lazy val root = (project in file("."))
     macros,protocol,plugins,sparkMonitorPlugin,communication,kernelApi,client,scalaInterpreter,sqlInterpreter,kernel
   )
   .dependsOn(
-    macros,protocol,communication,kernelApi,client,scalaInterpreter,sqlInterpreter,kernel,sparkMonitorPlugin
+    macros,protocol,communication,kernelApi,client,scalaInterpreter,sqlInterpreter,kernel
   )
 
 /**
@@ -146,7 +146,7 @@ lazy val protocol = (project in file("protocol"))
   */
 lazy val plugins = (project in file("plugins"))
   .settings(name := "toree-plugins")
-  .dependsOn(macros, protocol)
+  .dependsOn(macros)
 
 /**
   * Project representing the SparkMonitor plugin for Toree.

spark-monitor-plugin/build.sbt

@@ -25,4 +25,24 @@ libraryDependencies ++= Seq(
 )
 
 // Test dependencies
-libraryDependencies += Dependencies.scalaCompiler.value % "test"
+libraryDependencies += Dependencies.scalaCompiler.value % "test"
+
+// Assembly configuration for separate jar
+enablePlugins(AssemblyPlugin)
+
+assembly / assemblyJarName := s"spark-monitor-plugin-${version.value}.jar"
+
+assembly / assemblyMergeStrategy := {
+  case "module-info.class" => MergeStrategy.discard
+  case PathList("META-INF", "versions", "9", "module-info.class") => MergeStrategy.discard
+  case PathList("META-INF", xs @ _*) => MergeStrategy.discard
+  case x =>
+    val oldStrategy = (assembly / assemblyMergeStrategy).value
+    oldStrategy(x)
+}
+
+assembly / assemblyOption ~= {
+  _.withIncludeScala(false)
+}
+
+assembly / test := {}