RSocket Proxy for Prometheus monitoring

- Rename spring-cloud-dataflow-samples/tree/master/micrometer to spring-cloud-dataflow-samples/tree/master/micrometer-samples
 - Rename spring-cloud-dataflow-samples/tree/master/micrometer/tasks to spring-cloud-dataflow-samples/tree/master/micrometer-samples/task-apps
 - Add the apps under spring-cloud-dataflow-samples/tree/master/micrometer/stream-apps
 - Describe or cross-link the description of the new architecture in the root README
 - Add microsite SCDF monitoring links

 Resolves #122

monitoring-samples/README.md

@@ -0,0 +1,34 @@
+# Monitoring Architecture: Spring Cloud Data Flow + Prometheus RSocket Proxy
+
+The Data Flow metrics architecture is designed around the [Micrometer](https://micrometer.io/) library - vendor-neutral application metrics facade.
+The Spring Cloud Data Flow server leverages the [Prometheus RSocket Proxy](https://github.com/micrometer-metrics/prometheus-rsocket-proxy), 
+for monitoring of `tasks`, which are short lived, as well as long lived `stream` applications. 
+The RSocket based monitoring architecture is reusable across the Local, Kubernetes and Cloud Foundry platforms. 
+
+The prebuilt `stream` and `task` applications support the Prometheus Proxy RSocket monitoring architecture. 
+
+The [stream-apps](./stream-apps/) samples shows how to enable monitoring for custom built `source`, `processor` and `sink` apps.  
+
+The [task-apps](./task-apps/) sample shows how to enable monitoring for custom built `task` apps.
+
+The following image shows the general architecture of how the Stream applications are monitored:
+
+![Stream App Monitoring](./images/SCDF-monitoring-prometheus-streams.png)
+
+and the same architecture is used for monitoring the tasks as well. 
+ 
+![Stream App Monitoring](./images/SCDF-monitoring-prometheus-tasks.png)
+
+Prometheus is configured to scrape each rsocket-proxy instance. 
+Proxies in turn use the RSocket connection to pull metrics from each application. 
+The scraped metrics are then viewable through Grafana dashboards. 
+
+Following animated diagram shows the metrics collection flow:
+ 
+![Stream App Monitoring](./images/SCDF-monitoring-promethesu-proxy.gif)
+
+#### Spring Cloud Data Flow Monitoring Related Documentation
+
+- [SCDF Monitoring](https://dataflow.spring.io/docs/2.3.0.SNAPSHOT/concepts/monitoring/)
+- [Stream Monitoring with Prometheus and InfluxDB](https://dataflow.spring.io/docs/2.3.0.SNAPSHOT/feature-guides/streams/monitoring/).
+- [Task and Batch Monitoring with Prometheus and InfluxDB](https://dataflow.spring.io/docs/2.3.0.SNAPSHOT/feature-guides/batch/monitoring/#task-and-batch-monitoring-with-prometheus-and-influxdb)

monitoring-samples/stream-apps/README.md

@@ -0,0 +1,43 @@
+# Stream Apps Monitoring
+
+Add `org.springframework.cloud:spring-cloud-stream` and `org.springframework.cloud:spring-cloud-starter-stream-rabbit` to your Spring Boot application 
+POM to turn it into Stream Cloud Stream Application:
+
+```xml
+    <dependency>
+        <groupId>org.springframework.cloud</groupId>
+        <artifactId>spring-cloud-stream</artifactId>
+    </dependency>
+    
+    <dependency>
+        <groupId>org.springframework.cloud</groupId>
+        <artifactId>spring-cloud-starter-stream-rabbit</artifactId>
+    </dependency>
+```
+
+To replace Rabbit by Kafka binder use the `org.springframework.cloud:spring-cloud-starter-stream-kafka` dependency instead instead.
+
+To enable SCDF Prometheus Proxy monitoring for your application you would need to add the following additional additional dependencies: 
+
+```xml
+    <dependency>
+        <groupId>org.springframework.cloud.stream.app</groupId>
+        <artifactId>app-starters-micrometer-common</artifactId>
+        <version>2.1.2.RELEASE</version>
+    </dependency>
+    <dependency>
+        <groupId>io.micrometer</groupId>
+        <artifactId>micrometer-registry-prometheus</artifactId>
+    </dependency>    
+    <dependency>
+        <groupId>io.micrometer.prometheus</groupId>
+        <artifactId>prometheus-rsocket-spring</artifactId>
+        <version>0.9.0</version>
+    </dependency>
+```
+
+The `micrometer-registry-prometheus` amd `prometheus-rsocket-spring` activate the Micrometer Prometheus support for RSocket Proxy meter registry.
+The `app-starters-micrometer-common` would inject some common metrics Tags such as `stream.name`, `stream.app.label`, `application.type` and `application.guid`.
+Later are used in the SCDF Grafna Dashboards to visualize the Stream Application rates, throughput and so on.  
+
+To find more about the Spring Cloud Data Flow Monitoring architecture visit the [Stream Monitoring with Prometheus and InfluxDB](https://dataflow.spring.io/docs/2.3.0.SNAPSHOT/feature-guides/streams/monitoring/) documentation. 

monitoring-samples/stream-apps/demo-processor/.mvn/wrapper/MavenWrapperDownloader.java

@@ -0,0 +1,118 @@
+/*
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements.  See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership.  The ASF licenses this file
+to you 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
+
+  https://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.
+*/
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.net.URL;
+import java.nio.channels.Channels;
+import java.nio.channels.ReadableByteChannel;
+import java.util.Properties;
+
+public class MavenWrapperDownloader {
+
+	/**
+	 * Default URL to download the maven-wrapper.jar from, if no 'downloadUrl' is provided.
+	 */
+	private static final String DEFAULT_DOWNLOAD_URL =
+			"https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.4.2/maven-wrapper-0.4.2.jar";
+
+	/**
+	 * Path to the maven-wrapper.properties file, which might contain a downloadUrl property to
+	 * use instead of the default one.
+	 */
+	private static final String MAVEN_WRAPPER_PROPERTIES_PATH =
+			".mvn/wrapper/maven-wrapper.properties";
+
+	/**
+	 * Path where the maven-wrapper.jar will be saved to.
+	 */
+	private static final String MAVEN_WRAPPER_JAR_PATH =
+			".mvn/wrapper/maven-wrapper.jar";
+
+	/**
+	 * Name of the property which should be used to override the default download url for the wrapper.
+	 */
+	private static final String PROPERTY_NAME_WRAPPER_URL = "wrapperUrl";
+
+	public static void main(String args[]) {
+		System.out.println("- Downloader started");
+		File baseDirectory = new File(args[0]);
+		System.out.println("- Using base directory: " + baseDirectory.getAbsolutePath());
+
+		// If the maven-wrapper.properties exists, read it and check if it contains a custom
+		// wrapperUrl parameter.
+		File mavenWrapperPropertyFile = new File(baseDirectory, MAVEN_WRAPPER_PROPERTIES_PATH);
+		String url = DEFAULT_DOWNLOAD_URL;
+		if (mavenWrapperPropertyFile.exists()) {
+			FileInputStream mavenWrapperPropertyFileInputStream = null;
+			try {
+				mavenWrapperPropertyFileInputStream = new FileInputStream(mavenWrapperPropertyFile);
+				Properties mavenWrapperProperties = new Properties();
+				mavenWrapperProperties.load(mavenWrapperPropertyFileInputStream);
+				url = mavenWrapperProperties.getProperty(PROPERTY_NAME_WRAPPER_URL, url);
+			}
+			catch (IOException e) {
+				System.out.println("- ERROR loading '" + MAVEN_WRAPPER_PROPERTIES_PATH + "'");
+			}
+			finally {
+				try {
+					if (mavenWrapperPropertyFileInputStream != null) {
+						mavenWrapperPropertyFileInputStream.close();
+					}
+				}
+				catch (IOException e) {
+					// Ignore ...
+				}
+			}
+		}
+		System.out.println("- Downloading from: : " + url);
+
+		File outputFile = new File(baseDirectory.getAbsolutePath(), MAVEN_WRAPPER_JAR_PATH);
+		if (!outputFile.getParentFile().exists()) {
+			if (!outputFile.getParentFile().mkdirs()) {
+				System.out.println(
+						"- ERROR creating output direcrory '" + outputFile.getParentFile().getAbsolutePath() + "'");
+			}
+		}
+		System.out.println("- Downloading to: " + outputFile.getAbsolutePath());
+		try {
+			downloadFileFromURL(url, outputFile);
+			System.out.println("Done");
+			System.exit(0);
+		}
+		catch (Throwable e) {
+			System.out.println("- Error downloading");
+			e.printStackTrace();
+			System.exit(1);
+		}
+	}
+
+	private static void downloadFileFromURL(String urlString, File destination) throws Exception {
+		URL website = new URL(urlString);
+		ReadableByteChannel rbc;
+		rbc = Channels.newChannel(website.openStream());
+		FileOutputStream fos = new FileOutputStream(destination);
+		fos.getChannel().transferFrom(rbc, 0, Long.MAX_VALUE);
+		fos.close();
+		rbc.close();
+	}
+
+}

monitoring-samples/stream-apps/demo-processor/mvnw

@@ -0,0 +1,298 @@
+#!/bin/sh
+# ----------------------------------------------------------------------------
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you 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
+#
+#    https://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.
+# ----------------------------------------------------------------------------
+
+# ----------------------------------------------------------------------------
+# Maven2 Start Up Batch script
+#
+# Required ENV vars:
+# ------------------
+#   JAVA_HOME - location of a JDK home dir
+#
+# Optional ENV vars
+# -----------------
+#   M2_HOME - location of maven2's installed home dir
+#   MAVEN_OPTS - parameters passed to the Java VM when running Maven
+#     e.g. to debug Maven itself, use
+#       set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+#   MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+# ----------------------------------------------------------------------------
+
+if [ -z "$MAVEN_SKIP_RC" ]; then
+
+  if [ -f /etc/mavenrc ]; then
+    . /etc/mavenrc
+  fi
+
+  if [ -f "$HOME/.mavenrc" ]; then
+    . "$HOME/.mavenrc"
+  fi
+
+fi
+
+# OS specific support.  $var _must_ be set to either true or false.
+cygwin=false
+darwin=false
+mingw=false
+case "$(uname)" in
+CYGWIN*) cygwin=true ;;
+MINGW*) mingw=true ;;
+Darwin*)
+  darwin=true
+  # Use /usr/libexec/java_home if available, otherwise fall back to /Library/Java/Home
+  # See https://developer.apple.com/library/mac/qa/qa1170/_index.html
+  if [ -z "$JAVA_HOME" ]; then
+    if [ -x "/usr/libexec/java_home" ]; then
+      export JAVA_HOME="$(/usr/libexec/java_home)"
+    else
+      export JAVA_HOME="/Library/Java/Home"
+    fi
+  fi
+  ;;
+esac
+
+if [ -z "$JAVA_HOME" ]; then
+  if [ -r /etc/gentoo-release ]; then
+    JAVA_HOME=$(java-config --jre-home)
+  fi
+fi
+
+if [ -z "$M2_HOME" ]; then
+  ## resolve links - $0 may be a link to maven's home
+  PRG="$0"
+
+  # need this for relative symlinks
+  while [ -h "$PRG" ]; do
+    ls=$(ls -ld "$PRG")
+    link=$(expr "$ls" : '.*-> \(.*\)$')
+    if expr "$link" : '/.*' >/dev/null; then
+      PRG="$link"
+    else
+      PRG="$(dirname "$PRG")/$link"
+    fi
+  done
+
+  saveddir=$(pwd)
+
+  M2_HOME=$(dirname "$PRG")/..
+
+  # make it fully qualified
+  M2_HOME=$(cd "$M2_HOME" && pwd)
+
+  cd "$saveddir"
+  # echo Using m2 at $M2_HOME
+fi
+
+# For Cygwin, ensure paths are in UNIX format before anything is touched
+if $cygwin; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=$(cygpath --unix "$M2_HOME")
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=$(cygpath --unix "$JAVA_HOME")
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=$(cygpath --path --unix "$CLASSPATH")
+fi
+
+# For Mingw, ensure paths are in UNIX format before anything is touched
+if $mingw; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME="$( (
+      cd "$M2_HOME"
+      pwd
+    ))"
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME="$( (
+      cd "$JAVA_HOME"
+      pwd
+    ))"
+  # TODO classpath?
+fi
+
+if [ -z "$JAVA_HOME" ]; then
+  javaExecutable="$(which javac)"
+  if [ -n "$javaExecutable" ] && ! [ "$(expr \"$javaExecutable\" : '\([^ ]*\)')" = "no" ]; then
+    # readlink(1) is not available as standard on Solaris 10.
+    readLink=$(which readlink)
+    if [ ! $(expr "$readLink" : '\([^ ]*\)') = "no" ]; then
+      if $darwin; then
+        javaHome="$(dirname \"$javaExecutable\")"
+        javaExecutable="$(cd \"$javaHome\" && pwd -P)/javac"
+      else
+        javaExecutable="$(readlink -f \"$javaExecutable\")"
+      fi
+      javaHome="$(dirname \"$javaExecutable\")"
+      javaHome=$(expr "$javaHome" : '\(.*\)/bin')
+      JAVA_HOME="$javaHome"
+      export JAVA_HOME
+    fi
+  fi
+fi
+
+if [ -z "$JAVACMD" ]; then
+  if [ -n "$JAVA_HOME" ]; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ]; then
+      # IBM's JDK on AIX uses strange locations for the executables
+      JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+      JAVACMD="$JAVA_HOME/bin/java"
+    fi
+  else
+    JAVACMD="$(which java)"
+  fi
+fi
+
+if [ ! -x "$JAVACMD" ]; then
+  echo "Error: JAVA_HOME is not defined correctly." >&2
+  echo "  We cannot execute $JAVACMD" >&2
+  exit 1
+fi
+
+if [ -z "$JAVA_HOME" ]; then
+  echo "Warning: JAVA_HOME environment variable is not set."
+fi
+
+CLASSWORLDS_LAUNCHER=org.codehaus.plexus.classworlds.launcher.Launcher
+
+# traverses directory structure from process work directory to filesystem root
+# first directory with .mvn subdirectory is considered project base directory
+find_maven_basedir() {
+
+  if [ -z "$1" ]; then
+    echo "Path not specified to find_maven_basedir"
+    return 1
+  fi
+
+  basedir="$1"
+  wdir="$1"
+  while [ "$wdir" != '/' ]; do
+    if [ -d "$wdir"/.mvn ]; then
+      basedir=$wdir
+      break
+    fi
+    # workaround for JBEAP-8937 (on Solaris 10/Sparc)
+    if [ -d "${wdir}" ]; then
+      wdir=$(
+        cd "$wdir/.."
+        pwd
+      )
+    fi
+    # end of workaround
+  done
+  echo "${basedir}"
+}
+
+# concatenates all lines of a file
+concat_lines() {
+  if [ -f "$1" ]; then
+    echo "$(tr -s '\n' ' ' <"$1")"
+  fi
+}
+
+BASE_DIR=$(find_maven_basedir "$(pwd)")
+if [ -z "$BASE_DIR" ]; then
+  exit 1
+fi
+
+##########################################################################################
+# Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+# This allows using the maven wrapper in projects that prohibit checking in binary data.
+##########################################################################################
+if [ -r "$BASE_DIR/.mvn/wrapper/maven-wrapper.jar" ]; then
+  if [ "$MVNW_VERBOSE" = true ]; then
+    echo "Found .mvn/wrapper/maven-wrapper.jar"
+  fi
+else
+  if [ "$MVNW_VERBOSE" = true ]; then
+    echo "Couldn't find .mvn/wrapper/maven-wrapper.jar, downloading it ..."
+  fi
+  jarUrl="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.4.2/maven-wrapper-0.4.2.jar"
+  while IFS="=" read key value; do
+    case "$key" in wrapperUrl)
+      jarUrl="$value"
+      break
+      ;;
+    esac
+  done <"$BASE_DIR/.mvn/wrapper/maven-wrapper.properties"
+  if [ "$MVNW_VERBOSE" = true ]; then
+    echo "Downloading from: $jarUrl"
+  fi
+  wrapperJarPath="$BASE_DIR/.mvn/wrapper/maven-wrapper.jar"
+
+  if command -v wget >/dev/null; then
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Found wget ... using wget"
+    fi
+    wget "$jarUrl" -O "$wrapperJarPath"
+  elif command -v curl >/dev/null; then
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Found curl ... using curl"
+    fi
+    curl -o "$wrapperJarPath" "$jarUrl"
+  else
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Falling back to using Java to download"
+    fi
+    javaClass="$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.java"
+    if [ -e "$javaClass" ]; then
+      if [ ! -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo " - Compiling MavenWrapperDownloader.java ..."
+        fi
+        # Compiling the Java class
+        ("$JAVA_HOME/bin/javac" "$javaClass")
+      fi
+      if [ -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then
+        # Running the downloader
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo " - Running MavenWrapperDownloader.java ..."
+        fi
+        ("$JAVA_HOME/bin/java" -cp .mvn/wrapper MavenWrapperDownloader "$MAVEN_PROJECTBASEDIR")
+      fi
+    fi
+  fi
+fi
+##########################################################################################
+# End of extension
+##########################################################################################
+
+export MAVEN_PROJECTBASEDIR=${MAVEN_BASEDIR:-"$BASE_DIR"}
+if [ "$MVNW_VERBOSE" = true ]; then
+  echo $MAVEN_PROJECTBASEDIR
+fi
+MAVEN_OPTS="$(concat_lines "$MAVEN_PROJECTBASEDIR/.mvn/jvm.config") $MAVEN_OPTS"
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=$(cygpath --path --windows "$M2_HOME")
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=$(cygpath --path --windows "$JAVA_HOME")
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=$(cygpath --path --windows "$CLASSPATH")
+  [ -n "$MAVEN_PROJECTBASEDIR" ] &&
+    MAVEN_PROJECTBASEDIR=$(cygpath --path --windows "$MAVEN_PROJECTBASEDIR")
+fi
+
+WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+exec "$JAVACMD" \
+  $MAVEN_OPTS \
+  -classpath "$MAVEN_PROJECTBASEDIR/.mvn/wrapper/maven-wrapper.jar" \
+  "-Dmaven.home=${M2_HOME}" "-Dmaven.multiModuleProjectDirectory=${MAVEN_PROJECTBASEDIR}" \
+  ${WRAPPER_LAUNCHER} $MAVEN_CONFIG "$@"

monitoring-samples/stream-apps/demo-processor/pom.xml

@@ -0,0 +1,82 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<parent>
+		<groupId>org.springframework.boot</groupId>
+		<artifactId>spring-boot-starter-parent</artifactId>
+		<version>2.1.8.RELEASE</version>
+		<relativePath/> <!-- lookup parent from repository -->
+	</parent>
+	<groupId>com.example</groupId>
+	<artifactId>demo-processor</artifactId>
+	<version>0.0.1-SNAPSHOT</version>
+	<name>demo-processor</name>
+	<description>Demo project for Spring Boot</description>
+
+	<properties>
+		<java.version>1.8</java.version>
+		<spring-cloud.version>Greenwich.SR3</spring-cloud.version>
+	</properties>
+
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework.cloud</groupId>
+			<artifactId>spring-cloud-stream</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.cloud</groupId>
+			<artifactId>spring-cloud-starter-stream-rabbit</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.cloud.stream.app</groupId>
+			<artifactId>app-starters-micrometer-common</artifactId>
+			<version>2.1.2.RELEASE</version>
+		</dependency>
+
+		<dependency>
+			<groupId>io.micrometer</groupId>
+			<artifactId>micrometer-registry-prometheus</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>io.micrometer.prometheus</groupId>
+			<artifactId>prometheus-rsocket-spring</artifactId>
+			<version>0.9.0</version>
+		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.cloud</groupId>
+			<artifactId>spring-cloud-stream-test-support</artifactId>
+			<scope>test</scope>
+		</dependency>
+	</dependencies>
+
+	<dependencyManagement>
+		<dependencies>
+			<dependency>
+				<groupId>org.springframework.cloud</groupId>
+				<artifactId>spring-cloud-dependencies</artifactId>
+				<version>${spring-cloud.version}</version>
+				<type>pom</type>
+				<scope>import</scope>
+			</dependency>
+		</dependencies>
+	</dependencyManagement>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.springframework.boot</groupId>
+				<artifactId>spring-boot-maven-plugin</artifactId>
+			</plugin>
+		</plugins>
+	</build>
+
+</project>

monitoring-samples/stream-apps/demo-processor/src/main/java/com/example/demoprocessor/DemoProcessorApplication.java

@@ -0,0 +1,23 @@
+package com.example.demoprocessor;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.cloud.stream.annotation.EnableBinding;
+import org.springframework.cloud.stream.annotation.StreamListener;
+import org.springframework.cloud.stream.messaging.Processor;
+import org.springframework.messaging.handler.annotation.SendTo;
+
+@SpringBootApplication
+@EnableBinding(Processor.class)
+public class DemoProcessorApplication {
+
+	@StreamListener(Processor.INPUT)
+	@SendTo(Processor.OUTPUT)
+	public String myProcessor(String payload) {
+		return "Processed: " + payload;
+	}
+
+	public static void main(String[] args) {
+		SpringApplication.run(DemoProcessorApplication.class, args);
+	}
+}

monitoring-samples/stream-apps/demo-processor/src/main/resources/application.properties

@@ -0,0 +1 @@
+

monitoring-samples/stream-apps/demo-processor/src/test/java/com/example/demoprocessor/DemoProcessorApplicationTests.java

@@ -0,0 +1,17 @@
+package com.example.demoprocessor;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.junit4.SpringRunner;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest
+public class DemoProcessorApplicationTests {
+
+	@Test
+	public void contextLoads() {
+	}
+
+}

monitoring-samples/stream-apps/demo-sink/.mvn/wrapper/MavenWrapperDownloader.java

@@ -0,0 +1,118 @@
+/*
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements.  See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership.  The ASF licenses this file
+to you 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
+
+  https://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.
+*/
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.net.URL;
+import java.nio.channels.Channels;
+import java.nio.channels.ReadableByteChannel;
+import java.util.Properties;
+
+public class MavenWrapperDownloader {
+
+	/**
+	 * Default URL to download the maven-wrapper.jar from, if no 'downloadUrl' is provided.
+	 */
+	private static final String DEFAULT_DOWNLOAD_URL =
+			"https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.4.2/maven-wrapper-0.4.2.jar";
+
+	/**
+	 * Path to the maven-wrapper.properties file, which might contain a downloadUrl property to
+	 * use instead of the default one.
+	 */
+	private static final String MAVEN_WRAPPER_PROPERTIES_PATH =
+			".mvn/wrapper/maven-wrapper.properties";
+
+	/**
+	 * Path where the maven-wrapper.jar will be saved to.
+	 */
+	private static final String MAVEN_WRAPPER_JAR_PATH =
+			".mvn/wrapper/maven-wrapper.jar";
+
+	/**
+	 * Name of the property which should be used to override the default download url for the wrapper.
+	 */
+	private static final String PROPERTY_NAME_WRAPPER_URL = "wrapperUrl";
+
+	public static void main(String args[]) {
+		System.out.println("- Downloader started");
+		File baseDirectory = new File(args[0]);
+		System.out.println("- Using base directory: " + baseDirectory.getAbsolutePath());
+
+		// If the maven-wrapper.properties exists, read it and check if it contains a custom
+		// wrapperUrl parameter.
+		File mavenWrapperPropertyFile = new File(baseDirectory, MAVEN_WRAPPER_PROPERTIES_PATH);
+		String url = DEFAULT_DOWNLOAD_URL;
+		if (mavenWrapperPropertyFile.exists()) {
+			FileInputStream mavenWrapperPropertyFileInputStream = null;
+			try {
+				mavenWrapperPropertyFileInputStream = new FileInputStream(mavenWrapperPropertyFile);
+				Properties mavenWrapperProperties = new Properties();
+				mavenWrapperProperties.load(mavenWrapperPropertyFileInputStream);
+				url = mavenWrapperProperties.getProperty(PROPERTY_NAME_WRAPPER_URL, url);
+			}
+			catch (IOException e) {
+				System.out.println("- ERROR loading '" + MAVEN_WRAPPER_PROPERTIES_PATH + "'");
+			}
+			finally {
+				try {
+					if (mavenWrapperPropertyFileInputStream != null) {
+						mavenWrapperPropertyFileInputStream.close();
+					}
+				}
+				catch (IOException e) {
+					// Ignore ...
+				}
+			}
+		}
+		System.out.println("- Downloading from: : " + url);
+
+		File outputFile = new File(baseDirectory.getAbsolutePath(), MAVEN_WRAPPER_JAR_PATH);
+		if (!outputFile.getParentFile().exists()) {
+			if (!outputFile.getParentFile().mkdirs()) {
+				System.out.println(
+						"- ERROR creating output direcrory '" + outputFile.getParentFile().getAbsolutePath() + "'");
+			}
+		}
+		System.out.println("- Downloading to: " + outputFile.getAbsolutePath());
+		try {
+			downloadFileFromURL(url, outputFile);
+			System.out.println("Done");
+			System.exit(0);
+		}
+		catch (Throwable e) {
+			System.out.println("- Error downloading");
+			e.printStackTrace();
+			System.exit(1);
+		}
+	}
+
+	private static void downloadFileFromURL(String urlString, File destination) throws Exception {
+		URL website = new URL(urlString);
+		ReadableByteChannel rbc;
+		rbc = Channels.newChannel(website.openStream());
+		FileOutputStream fos = new FileOutputStream(destination);
+		fos.getChannel().transferFrom(rbc, 0, Long.MAX_VALUE);
+		fos.close();
+		rbc.close();
+	}
+
+}

monitoring-samples/stream-apps/demo-sink/mvnw

@@ -0,0 +1,298 @@
+#!/bin/sh
+# ----------------------------------------------------------------------------
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you 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
+#
+#    https://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.
+# ----------------------------------------------------------------------------
+
+# ----------------------------------------------------------------------------
+# Maven2 Start Up Batch script
+#
+# Required ENV vars:
+# ------------------
+#   JAVA_HOME - location of a JDK home dir
+#
+# Optional ENV vars
+# -----------------
+#   M2_HOME - location of maven2's installed home dir
+#   MAVEN_OPTS - parameters passed to the Java VM when running Maven
+#     e.g. to debug Maven itself, use
+#       set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+#   MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+# ----------------------------------------------------------------------------
+
+if [ -z "$MAVEN_SKIP_RC" ]; then
+
+  if [ -f /etc/mavenrc ]; then
+    . /etc/mavenrc
+  fi
+
+  if [ -f "$HOME/.mavenrc" ]; then
+    . "$HOME/.mavenrc"
+  fi
+
+fi
+
+# OS specific support.  $var _must_ be set to either true or false.
+cygwin=false
+darwin=false
+mingw=false
+case "$(uname)" in
+CYGWIN*) cygwin=true ;;
+MINGW*) mingw=true ;;
+Darwin*)
+  darwin=true
+  # Use /usr/libexec/java_home if available, otherwise fall back to /Library/Java/Home
+  # See https://developer.apple.com/library/mac/qa/qa1170/_index.html
+  if [ -z "$JAVA_HOME" ]; then
+    if [ -x "/usr/libexec/java_home" ]; then
+      export JAVA_HOME="$(/usr/libexec/java_home)"
+    else
+      export JAVA_HOME="/Library/Java/Home"
+    fi
+  fi
+  ;;
+esac
+
+if [ -z "$JAVA_HOME" ]; then
+  if [ -r /etc/gentoo-release ]; then
+    JAVA_HOME=$(java-config --jre-home)
+  fi
+fi
+
+if [ -z "$M2_HOME" ]; then
+  ## resolve links - $0 may be a link to maven's home
+  PRG="$0"
+
+  # need this for relative symlinks
+  while [ -h "$PRG" ]; do
+    ls=$(ls -ld "$PRG")
+    link=$(expr "$ls" : '.*-> \(.*\)$')
+    if expr "$link" : '/.*' >/dev/null; then
+      PRG="$link"
+    else
+      PRG="$(dirname "$PRG")/$link"
+    fi
+  done
+
+  saveddir=$(pwd)
+
+  M2_HOME=$(dirname "$PRG")/..
+
+  # make it fully qualified
+  M2_HOME=$(cd "$M2_HOME" && pwd)
+
+  cd "$saveddir"
+  # echo Using m2 at $M2_HOME
+fi
+
+# For Cygwin, ensure paths are in UNIX format before anything is touched
+if $cygwin; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=$(cygpath --unix "$M2_HOME")
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=$(cygpath --unix "$JAVA_HOME")
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=$(cygpath --path --unix "$CLASSPATH")
+fi
+
+# For Mingw, ensure paths are in UNIX format before anything is touched
+if $mingw; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME="$( (
+      cd "$M2_HOME"
+      pwd
+    ))"
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME="$( (
+      cd "$JAVA_HOME"
+      pwd
+    ))"
+  # TODO classpath?
+fi
+
+if [ -z "$JAVA_HOME" ]; then
+  javaExecutable="$(which javac)"
+  if [ -n "$javaExecutable" ] && ! [ "$(expr \"$javaExecutable\" : '\([^ ]*\)')" = "no" ]; then
+    # readlink(1) is not available as standard on Solaris 10.
+    readLink=$(which readlink)
+    if [ ! $(expr "$readLink" : '\([^ ]*\)') = "no" ]; then
+      if $darwin; then
+        javaHome="$(dirname \"$javaExecutable\")"
+        javaExecutable="$(cd \"$javaHome\" && pwd -P)/javac"
+      else
+        javaExecutable="$(readlink -f \"$javaExecutable\")"
+      fi
+      javaHome="$(dirname \"$javaExecutable\")"
+      javaHome=$(expr "$javaHome" : '\(.*\)/bin')
+      JAVA_HOME="$javaHome"
+      export JAVA_HOME
+    fi
+  fi
+fi
+
+if [ -z "$JAVACMD" ]; then
+  if [ -n "$JAVA_HOME" ]; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ]; then
+      # IBM's JDK on AIX uses strange locations for the executables
+      JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+      JAVACMD="$JAVA_HOME/bin/java"
+    fi
+  else
+    JAVACMD="$(which java)"
+  fi
+fi
+
+if [ ! -x "$JAVACMD" ]; then
+  echo "Error: JAVA_HOME is not defined correctly." >&2
+  echo "  We cannot execute $JAVACMD" >&2
+  exit 1
+fi
+
+if [ -z "$JAVA_HOME" ]; then
+  echo "Warning: JAVA_HOME environment variable is not set."
+fi
+
+CLASSWORLDS_LAUNCHER=org.codehaus.plexus.classworlds.launcher.Launcher
+
+# traverses directory structure from process work directory to filesystem root
+# first directory with .mvn subdirectory is considered project base directory
+find_maven_basedir() {
+
+  if [ -z "$1" ]; then
+    echo "Path not specified to find_maven_basedir"
+    return 1
+  fi
+
+  basedir="$1"
+  wdir="$1"
+  while [ "$wdir" != '/' ]; do
+    if [ -d "$wdir"/.mvn ]; then
+      basedir=$wdir
+      break
+    fi
+    # workaround for JBEAP-8937 (on Solaris 10/Sparc)
+    if [ -d "${wdir}" ]; then
+      wdir=$(
+        cd "$wdir/.."
+        pwd
+      )
+    fi
+    # end of workaround
+  done
+  echo "${basedir}"
+}
+
+# concatenates all lines of a file
+concat_lines() {
+  if [ -f "$1" ]; then
+    echo "$(tr -s '\n' ' ' <"$1")"
+  fi
+}
+
+BASE_DIR=$(find_maven_basedir "$(pwd)")
+if [ -z "$BASE_DIR" ]; then
+  exit 1
+fi
+
+##########################################################################################
+# Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+# This allows using the maven wrapper in projects that prohibit checking in binary data.
+##########################################################################################
+if [ -r "$BASE_DIR/.mvn/wrapper/maven-wrapper.jar" ]; then
+  if [ "$MVNW_VERBOSE" = true ]; then
+    echo "Found .mvn/wrapper/maven-wrapper.jar"
+  fi
+else
+  if [ "$MVNW_VERBOSE" = true ]; then
+    echo "Couldn't find .mvn/wrapper/maven-wrapper.jar, downloading it ..."
+  fi
+  jarUrl="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.4.2/maven-wrapper-0.4.2.jar"
+  while IFS="=" read key value; do
+    case "$key" in wrapperUrl)
+      jarUrl="$value"
+      break
+      ;;
+    esac
+  done <"$BASE_DIR/.mvn/wrapper/maven-wrapper.properties"
+  if [ "$MVNW_VERBOSE" = true ]; then
+    echo "Downloading from: $jarUrl"
+  fi
+  wrapperJarPath="$BASE_DIR/.mvn/wrapper/maven-wrapper.jar"
+
+  if command -v wget >/dev/null; then
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Found wget ... using wget"
+    fi
+    wget "$jarUrl" -O "$wrapperJarPath"
+  elif command -v curl >/dev/null; then
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Found curl ... using curl"
+    fi
+    curl -o "$wrapperJarPath" "$jarUrl"
+  else
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Falling back to using Java to download"
+    fi
+    javaClass="$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.java"
+    if [ -e "$javaClass" ]; then
+      if [ ! -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo " - Compiling MavenWrapperDownloader.java ..."
+        fi
+        # Compiling the Java class
+        ("$JAVA_HOME/bin/javac" "$javaClass")
+      fi
+      if [ -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then
+        # Running the downloader
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo " - Running MavenWrapperDownloader.java ..."
+        fi
+        ("$JAVA_HOME/bin/java" -cp .mvn/wrapper MavenWrapperDownloader "$MAVEN_PROJECTBASEDIR")
+      fi
+    fi
+  fi
+fi
+##########################################################################################
+# End of extension
+##########################################################################################
+
+export MAVEN_PROJECTBASEDIR=${MAVEN_BASEDIR:-"$BASE_DIR"}
+if [ "$MVNW_VERBOSE" = true ]; then
+  echo $MAVEN_PROJECTBASEDIR
+fi
+MAVEN_OPTS="$(concat_lines "$MAVEN_PROJECTBASEDIR/.mvn/jvm.config") $MAVEN_OPTS"
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=$(cygpath --path --windows "$M2_HOME")
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=$(cygpath --path --windows "$JAVA_HOME")
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=$(cygpath --path --windows "$CLASSPATH")
+  [ -n "$MAVEN_PROJECTBASEDIR" ] &&
+    MAVEN_PROJECTBASEDIR=$(cygpath --path --windows "$MAVEN_PROJECTBASEDIR")
+fi
+
+WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+exec "$JAVACMD" \
+  $MAVEN_OPTS \
+  -classpath "$MAVEN_PROJECTBASEDIR/.mvn/wrapper/maven-wrapper.jar" \
+  "-Dmaven.home=${M2_HOME}" "-Dmaven.multiModuleProjectDirectory=${MAVEN_PROJECTBASEDIR}" \
+  ${WRAPPER_LAUNCHER} $MAVEN_CONFIG "$@"

monitoring-samples/stream-apps/demo-sink/pom.xml

@@ -0,0 +1,83 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<parent>
+		<groupId>org.springframework.boot</groupId>
+		<artifactId>spring-boot-starter-parent</artifactId>
+		<version>2.1.8.RELEASE</version>
+		<relativePath/> <!-- lookup parent from repository -->
+	</parent>
+	<groupId>com.example</groupId>
+	<artifactId>demo-sink</artifactId>
+	<version>0.0.1-SNAPSHOT</version>
+	<name>demo-sink</name>
+	<description>Demo project for Spring Boot</description>
+
+	<properties>
+		<java.version>1.8</java.version>
+		<spring-cloud.version>Greenwich.SR3</spring-cloud.version>
+	</properties>
+
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework.cloud</groupId>
+			<artifactId>spring-cloud-stream</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.cloud</groupId>
+			<artifactId>spring-cloud-starter-stream-rabbit</artifactId>
+		</dependency>
+
+
+		<dependency>
+			<groupId>org.springframework.cloud.stream.app</groupId>
+			<artifactId>app-starters-micrometer-common</artifactId>
+			<version>2.1.2.RELEASE</version>
+		</dependency>
+		<dependency>
+			<groupId>io.micrometer</groupId>
+			<artifactId>micrometer-registry-prometheus</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>io.micrometer.prometheus</groupId>
+			<artifactId>prometheus-rsocket-spring</artifactId>
+			<version>0.9.0</version>
+		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.cloud</groupId>
+			<artifactId>spring-cloud-stream-test-support</artifactId>
+			<scope>test</scope>
+		</dependency>
+	</dependencies>
+
+	<dependencyManagement>
+		<dependencies>
+			<dependency>
+				<groupId>org.springframework.cloud</groupId>
+				<artifactId>spring-cloud-dependencies</artifactId>
+				<version>${spring-cloud.version}</version>
+				<type>pom</type>
+				<scope>import</scope>
+			</dependency>
+		</dependencies>
+	</dependencyManagement>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.springframework.boot</groupId>
+				<artifactId>spring-boot-maven-plugin</artifactId>
+			</plugin>
+		</plugins>
+	</build>
+
+</project>

monitoring-samples/stream-apps/demo-sink/src/main/java/com/example/demosink/DemoSinkApplication.java

@@ -0,0 +1,27 @@
+package com.example.demosink;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.cloud.stream.annotation.EnableBinding;
+import org.springframework.cloud.stream.annotation.StreamListener;
+import org.springframework.cloud.stream.messaging.Sink;
+
+@SpringBootApplication
+@EnableBinding(Sink.class)
+public class DemoSinkApplication {
+
+	private static final Logger logger = LoggerFactory.getLogger(DemoSinkApplication.class);
+
+	@StreamListener(Sink.INPUT)
+	public void myMessageHandler(String payload) {
+		logger.info("Received: " + payload);
+	}
+
+	public static void main(String[] args) {
+		SpringApplication.run(DemoSinkApplication.class, args);
+	}
+
+}

monitoring-samples/stream-apps/demo-sink/src/main/resources/application.properties

@@ -0,0 +1 @@
+

monitoring-samples/stream-apps/demo-sink/src/test/java/com/example/demosink/DemoSinkApplicationTests.java

@@ -0,0 +1,17 @@
+package com.example.demosink;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.junit4.SpringRunner;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest
+public class DemoSinkApplicationTests {
+
+	@Test
+	public void contextLoads() {
+	}
+
+}

monitoring-samples/stream-apps/demo-source/.gitignore

@@ -0,0 +1,31 @@
+HELP.md
+target/
+!.mvn/wrapper/maven-wrapper.jar
+!**/src/main/**
+!**/src/test/**
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+build/
+
+### VS Code ###
+.vscode/

monitoring-samples/stream-apps/demo-source/.mvn/wrapper/MavenWrapperDownloader.java

@@ -0,0 +1,118 @@
+/*
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements.  See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership.  The ASF licenses this file
+to you 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
+
+  https://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.
+*/
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.net.URL;
+import java.nio.channels.Channels;
+import java.nio.channels.ReadableByteChannel;
+import java.util.Properties;
+
+public class MavenWrapperDownloader {
+
+	/**
+	 * Default URL to download the maven-wrapper.jar from, if no 'downloadUrl' is provided.
+	 */
+	private static final String DEFAULT_DOWNLOAD_URL =
+			"https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.4.2/maven-wrapper-0.4.2.jar";
+
+	/**
+	 * Path to the maven-wrapper.properties file, which might contain a downloadUrl property to
+	 * use instead of the default one.
+	 */
+	private static final String MAVEN_WRAPPER_PROPERTIES_PATH =
+			".mvn/wrapper/maven-wrapper.properties";
+
+	/**
+	 * Path where the maven-wrapper.jar will be saved to.
+	 */
+	private static final String MAVEN_WRAPPER_JAR_PATH =
+			".mvn/wrapper/maven-wrapper.jar";
+
+	/**
+	 * Name of the property which should be used to override the default download url for the wrapper.
+	 */
+	private static final String PROPERTY_NAME_WRAPPER_URL = "wrapperUrl";
+
+	public static void main(String args[]) {
+		System.out.println("- Downloader started");
+		File baseDirectory = new File(args[0]);
+		System.out.println("- Using base directory: " + baseDirectory.getAbsolutePath());
+
+		// If the maven-wrapper.properties exists, read it and check if it contains a custom
+		// wrapperUrl parameter.
+		File mavenWrapperPropertyFile = new File(baseDirectory, MAVEN_WRAPPER_PROPERTIES_PATH);
+		String url = DEFAULT_DOWNLOAD_URL;
+		if (mavenWrapperPropertyFile.exists()) {
+			FileInputStream mavenWrapperPropertyFileInputStream = null;
+			try {
+				mavenWrapperPropertyFileInputStream = new FileInputStream(mavenWrapperPropertyFile);
+				Properties mavenWrapperProperties = new Properties();
+				mavenWrapperProperties.load(mavenWrapperPropertyFileInputStream);
+				url = mavenWrapperProperties.getProperty(PROPERTY_NAME_WRAPPER_URL, url);
+			}
+			catch (IOException e) {
+				System.out.println("- ERROR loading '" + MAVEN_WRAPPER_PROPERTIES_PATH + "'");
+			}
+			finally {
+				try {
+					if (mavenWrapperPropertyFileInputStream != null) {
+						mavenWrapperPropertyFileInputStream.close();
+					}
+				}
+				catch (IOException e) {
+					// Ignore ...
+				}
+			}
+		}
+		System.out.println("- Downloading from: : " + url);
+
+		File outputFile = new File(baseDirectory.getAbsolutePath(), MAVEN_WRAPPER_JAR_PATH);
+		if (!outputFile.getParentFile().exists()) {
+			if (!outputFile.getParentFile().mkdirs()) {
+				System.out.println(
+						"- ERROR creating output direcrory '" + outputFile.getParentFile().getAbsolutePath() + "'");
+			}
+		}
+		System.out.println("- Downloading to: " + outputFile.getAbsolutePath());
+		try {
+			downloadFileFromURL(url, outputFile);
+			System.out.println("Done");
+			System.exit(0);
+		}
+		catch (Throwable e) {
+			System.out.println("- Error downloading");
+			e.printStackTrace();
+			System.exit(1);
+		}
+	}
+
+	private static void downloadFileFromURL(String urlString, File destination) throws Exception {
+		URL website = new URL(urlString);
+		ReadableByteChannel rbc;
+		rbc = Channels.newChannel(website.openStream());
+		FileOutputStream fos = new FileOutputStream(destination);
+		fos.getChannel().transferFrom(rbc, 0, Long.MAX_VALUE);
+		fos.close();
+		rbc.close();
+	}
+
+}

monitoring-samples/stream-apps/demo-source/.mvn/wrapper/maven-wrapper.properties

@@ -0,0 +1 @@
+distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.6.0/apache-maven-3.6.0-bin.zip

monitoring-samples/stream-apps/demo-source/mvnw

@@ -0,0 +1,298 @@
+#!/bin/sh
+# ----------------------------------------------------------------------------
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you 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
+#
+#    https://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.
+# ----------------------------------------------------------------------------
+
+# ----------------------------------------------------------------------------
+# Maven2 Start Up Batch script
+#
+# Required ENV vars:
+# ------------------
+#   JAVA_HOME - location of a JDK home dir
+#
+# Optional ENV vars
+# -----------------
+#   M2_HOME - location of maven2's installed home dir
+#   MAVEN_OPTS - parameters passed to the Java VM when running Maven
+#     e.g. to debug Maven itself, use
+#       set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+#   MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+# ----------------------------------------------------------------------------
+
+if [ -z "$MAVEN_SKIP_RC" ]; then
+
+  if [ -f /etc/mavenrc ]; then
+    . /etc/mavenrc
+  fi
+
+  if [ -f "$HOME/.mavenrc" ]; then
+    . "$HOME/.mavenrc"
+  fi
+
+fi
+
+# OS specific support.  $var _must_ be set to either true or false.
+cygwin=false
+darwin=false
+mingw=false
+case "$(uname)" in
+CYGWIN*) cygwin=true ;;
+MINGW*) mingw=true ;;
+Darwin*)
+  darwin=true
+  # Use /usr/libexec/java_home if available, otherwise fall back to /Library/Java/Home
+  # See https://developer.apple.com/library/mac/qa/qa1170/_index.html
+  if [ -z "$JAVA_HOME" ]; then
+    if [ -x "/usr/libexec/java_home" ]; then
+      export JAVA_HOME="$(/usr/libexec/java_home)"
+    else
+      export JAVA_HOME="/Library/Java/Home"
+    fi
+  fi
+  ;;
+esac
+
+if [ -z "$JAVA_HOME" ]; then
+  if [ -r /etc/gentoo-release ]; then
+    JAVA_HOME=$(java-config --jre-home)
+  fi
+fi
+
+if [ -z "$M2_HOME" ]; then
+  ## resolve links - $0 may be a link to maven's home
+  PRG="$0"
+
+  # need this for relative symlinks
+  while [ -h "$PRG" ]; do
+    ls=$(ls -ld "$PRG")
+    link=$(expr "$ls" : '.*-> \(.*\)$')
+    if expr "$link" : '/.*' >/dev/null; then
+      PRG="$link"
+    else
+      PRG="$(dirname "$PRG")/$link"
+    fi
+  done
+
+  saveddir=$(pwd)
+
+  M2_HOME=$(dirname "$PRG")/..
+
+  # make it fully qualified
+  M2_HOME=$(cd "$M2_HOME" && pwd)
+
+  cd "$saveddir"
+  # echo Using m2 at $M2_HOME
+fi
+
+# For Cygwin, ensure paths are in UNIX format before anything is touched
+if $cygwin; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=$(cygpath --unix "$M2_HOME")
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=$(cygpath --unix "$JAVA_HOME")
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=$(cygpath --path --unix "$CLASSPATH")
+fi
+
+# For Mingw, ensure paths are in UNIX format before anything is touched
+if $mingw; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME="$( (
+      cd "$M2_HOME"
+      pwd
+    ))"
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME="$( (
+      cd "$JAVA_HOME"
+      pwd
+    ))"
+  # TODO classpath?
+fi
+
+if [ -z "$JAVA_HOME" ]; then
+  javaExecutable="$(which javac)"
+  if [ -n "$javaExecutable" ] && ! [ "$(expr \"$javaExecutable\" : '\([^ ]*\)')" = "no" ]; then
+    # readlink(1) is not available as standard on Solaris 10.
+    readLink=$(which readlink)
+    if [ ! $(expr "$readLink" : '\([^ ]*\)') = "no" ]; then
+      if $darwin; then
+        javaHome="$(dirname \"$javaExecutable\")"
+        javaExecutable="$(cd \"$javaHome\" && pwd -P)/javac"
+      else
+        javaExecutable="$(readlink -f \"$javaExecutable\")"
+      fi
+      javaHome="$(dirname \"$javaExecutable\")"
+      javaHome=$(expr "$javaHome" : '\(.*\)/bin')
+      JAVA_HOME="$javaHome"
+      export JAVA_HOME
+    fi
+  fi
+fi
+
+if [ -z "$JAVACMD" ]; then
+  if [ -n "$JAVA_HOME" ]; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ]; then
+      # IBM's JDK on AIX uses strange locations for the executables
+      JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+      JAVACMD="$JAVA_HOME/bin/java"
+    fi
+  else
+    JAVACMD="$(which java)"
+  fi
+fi
+
+if [ ! -x "$JAVACMD" ]; then
+  echo "Error: JAVA_HOME is not defined correctly." >&2
+  echo "  We cannot execute $JAVACMD" >&2
+  exit 1
+fi
+
+if [ -z "$JAVA_HOME" ]; then
+  echo "Warning: JAVA_HOME environment variable is not set."
+fi
+
+CLASSWORLDS_LAUNCHER=org.codehaus.plexus.classworlds.launcher.Launcher
+
+# traverses directory structure from process work directory to filesystem root
+# first directory with .mvn subdirectory is considered project base directory
+find_maven_basedir() {
+
+  if [ -z "$1" ]; then
+    echo "Path not specified to find_maven_basedir"
+    return 1
+  fi
+
+  basedir="$1"
+  wdir="$1"
+  while [ "$wdir" != '/' ]; do
+    if [ -d "$wdir"/.mvn ]; then
+      basedir=$wdir
+      break
+    fi
+    # workaround for JBEAP-8937 (on Solaris 10/Sparc)
+    if [ -d "${wdir}" ]; then
+      wdir=$(
+        cd "$wdir/.."
+        pwd
+      )
+    fi
+    # end of workaround
+  done
+  echo "${basedir}"
+}
+
+# concatenates all lines of a file
+concat_lines() {
+  if [ -f "$1" ]; then
+    echo "$(tr -s '\n' ' ' <"$1")"
+  fi
+}
+
+BASE_DIR=$(find_maven_basedir "$(pwd)")
+if [ -z "$BASE_DIR" ]; then
+  exit 1
+fi
+
+##########################################################################################
+# Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+# This allows using the maven wrapper in projects that prohibit checking in binary data.
+##########################################################################################
+if [ -r "$BASE_DIR/.mvn/wrapper/maven-wrapper.jar" ]; then
+  if [ "$MVNW_VERBOSE" = true ]; then
+    echo "Found .mvn/wrapper/maven-wrapper.jar"
+  fi
+else
+  if [ "$MVNW_VERBOSE" = true ]; then
+    echo "Couldn't find .mvn/wrapper/maven-wrapper.jar, downloading it ..."
+  fi
+  jarUrl="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.4.2/maven-wrapper-0.4.2.jar"
+  while IFS="=" read key value; do
+    case "$key" in wrapperUrl)
+      jarUrl="$value"
+      break
+      ;;
+    esac
+  done <"$BASE_DIR/.mvn/wrapper/maven-wrapper.properties"
+  if [ "$MVNW_VERBOSE" = true ]; then
+    echo "Downloading from: $jarUrl"
+  fi
+  wrapperJarPath="$BASE_DIR/.mvn/wrapper/maven-wrapper.jar"
+
+  if command -v wget >/dev/null; then
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Found wget ... using wget"
+    fi
+    wget "$jarUrl" -O "$wrapperJarPath"
+  elif command -v curl >/dev/null; then
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Found curl ... using curl"
+    fi
+    curl -o "$wrapperJarPath" "$jarUrl"
+  else
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Falling back to using Java to download"
+    fi
+    javaClass="$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.java"
+    if [ -e "$javaClass" ]; then
+      if [ ! -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo " - Compiling MavenWrapperDownloader.java ..."
+        fi
+        # Compiling the Java class
+        ("$JAVA_HOME/bin/javac" "$javaClass")
+      fi
+      if [ -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then
+        # Running the downloader
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo " - Running MavenWrapperDownloader.java ..."
+        fi
+        ("$JAVA_HOME/bin/java" -cp .mvn/wrapper MavenWrapperDownloader "$MAVEN_PROJECTBASEDIR")
+      fi
+    fi
+  fi
+fi
+##########################################################################################
+# End of extension
+##########################################################################################
+
+export MAVEN_PROJECTBASEDIR=${MAVEN_BASEDIR:-"$BASE_DIR"}
+if [ "$MVNW_VERBOSE" = true ]; then
+  echo $MAVEN_PROJECTBASEDIR
+fi
+MAVEN_OPTS="$(concat_lines "$MAVEN_PROJECTBASEDIR/.mvn/jvm.config") $MAVEN_OPTS"
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=$(cygpath --path --windows "$M2_HOME")
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=$(cygpath --path --windows "$JAVA_HOME")
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=$(cygpath --path --windows "$CLASSPATH")
+  [ -n "$MAVEN_PROJECTBASEDIR" ] &&
+    MAVEN_PROJECTBASEDIR=$(cygpath --path --windows "$MAVEN_PROJECTBASEDIR")
+fi
+
+WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+exec "$JAVACMD" \
+  $MAVEN_OPTS \
+  -classpath "$MAVEN_PROJECTBASEDIR/.mvn/wrapper/maven-wrapper.jar" \
+  "-Dmaven.home=${M2_HOME}" "-Dmaven.multiModuleProjectDirectory=${MAVEN_PROJECTBASEDIR}" \
+  ${WRAPPER_LAUNCHER} $MAVEN_CONFIG "$@"

monitoring-samples/stream-apps/demo-source/mvnw.cmd

@@ -0,0 +1,161 @@
+@REM ----------------------------------------------------------------------------
+@REM Licensed to the Apache Software Foundation (ASF) under one
+@REM or more contributor license agreements.  See the NOTICE file
+@REM distributed with this work for additional information
+@REM regarding copyright ownership.  The ASF licenses this file
+@REM to you under the Apache License, Version 2.0 (the
+@REM "License"); you may not use this file except in compliance
+@REM with the License.  You may obtain a copy of the License at
+@REM
+@REM    https://www.apache.org/licenses/LICENSE-2.0
+@REM
+@REM Unless required by applicable law or agreed to in writing,
+@REM software distributed under the License is distributed on an
+@REM "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+@REM KIND, either express or implied.  See the License for the
+@REM specific language governing permissions and limitations
+@REM under the License.
+@REM ----------------------------------------------------------------------------
+
+@REM ----------------------------------------------------------------------------
+@REM Maven2 Start Up Batch script
+@REM
+@REM Required ENV vars:
+@REM JAVA_HOME - location of a JDK home dir
+@REM
+@REM Optional ENV vars
+@REM M2_HOME - location of maven2's installed home dir
+@REM MAVEN_BATCH_ECHO - set to 'on' to enable the echoing of the batch commands
+@REM MAVEN_BATCH_PAUSE - set to 'on' to wait for a key stroke before ending
+@REM MAVEN_OPTS - parameters passed to the Java VM when running Maven
+@REM     e.g. to debug Maven itself, use
+@REM set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+@REM MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+@REM ----------------------------------------------------------------------------
+
+@REM Begin all REM lines with '@' in case MAVEN_BATCH_ECHO is 'on'
+@echo off
+@REM set title of command window
+title %0
+@REM enable echoing my setting MAVEN_BATCH_ECHO to 'on'
+@if "%MAVEN_BATCH_ECHO%" == "on"  echo %MAVEN_BATCH_ECHO%
+
+@REM set %HOME% to equivalent of $HOME
+if "%HOME%" == "" (set "HOME=%HOMEDRIVE%%HOMEPATH%")
+
+@REM Execute a user defined script before this one
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPre
+@REM check for pre script, once with legacy .bat ending and once with .cmd ending
+if exist "%HOME%\mavenrc_pre.bat" call "%HOME%\mavenrc_pre.bat"
+if exist "%HOME%\mavenrc_pre.cmd" call "%HOME%\mavenrc_pre.cmd"
+:skipRcPre
+
+@setlocal
+
+set ERROR_CODE=0
+
+@REM To isolate internal variables from possible post scripts, we use another setlocal
+@setlocal
+
+@REM ==== START VALIDATION ====
+if not "%JAVA_HOME%" == "" goto OkJHome
+
+echo.
+echo Error: JAVA_HOME not found in your environment. >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+:OkJHome
+if exist "%JAVA_HOME%\bin\java.exe" goto init
+
+echo.
+echo Error: JAVA_HOME is set to an invalid directory. >&2
+echo JAVA_HOME = "%JAVA_HOME%" >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+@REM ==== END VALIDATION ====
+
+:init
+
+@REM Find the project base dir, i.e. the directory that contains the folder ".mvn".
+@REM Fallback to current working directory if not found.
+
+set MAVEN_PROJECTBASEDIR=%MAVEN_BASEDIR%
+IF NOT "%MAVEN_PROJECTBASEDIR%"=="" goto endDetectBaseDir
+
+set EXEC_DIR=%CD%
+set WDIR=%EXEC_DIR%
+:findBaseDir
+IF EXIST "%WDIR%"\.mvn goto baseDirFound
+cd ..
+IF "%WDIR%"=="%CD%" goto baseDirNotFound
+set WDIR=%CD%
+goto findBaseDir
+
+:baseDirFound
+set MAVEN_PROJECTBASEDIR=%WDIR%
+cd "%EXEC_DIR%"
+goto endDetectBaseDir
+
+:baseDirNotFound
+set MAVEN_PROJECTBASEDIR=%EXEC_DIR%
+cd "%EXEC_DIR%"
+
+:endDetectBaseDir
+
+IF NOT EXIST "%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config" goto endReadAdditionalConfig
+
+@setlocal EnableExtensions EnableDelayedExpansion
+for /F "usebackq delims=" %%a in ("%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config") do set JVM_CONFIG_MAVEN_PROPS=!JVM_CONFIG_MAVEN_PROPS! %%a
+@endlocal & set JVM_CONFIG_MAVEN_PROPS=%JVM_CONFIG_MAVEN_PROPS%
+
+:endReadAdditionalConfig
+
+SET MAVEN_JAVA_EXE="%JAVA_HOME%\bin\java.exe"
+set WRAPPER_JAR="%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.jar"
+set WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+set DOWNLOAD_URL="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.4.2/maven-wrapper-0.4.2.jar"
+FOR /F "tokens=1,2 delims==" %%A IN (%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.properties) DO (
+	IF "%%A"=="wrapperUrl" SET DOWNLOAD_URL=%%B 
+)
+
+@REM Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+@REM This allows using the maven wrapper in projects that prohibit checking in binary data.
+if exist %WRAPPER_JAR% (
+    echo Found %WRAPPER_JAR%
+) else (
+    echo Couldn't find %WRAPPER_JAR%, downloading it ...
+	echo Downloading from: %DOWNLOAD_URL%
+    powershell -Command "(New-Object Net.WebClient).DownloadFile('%DOWNLOAD_URL%', '%WRAPPER_JAR%')"
+    echo Finished downloading %WRAPPER_JAR%
+)
+@REM End of extension
+
+%MAVEN_JAVA_EXE% %JVM_CONFIG_MAVEN_PROPS% %MAVEN_OPTS% %MAVEN_DEBUG_OPTS% -classpath %WRAPPER_JAR% "-Dmaven.multiModuleProjectDirectory=%MAVEN_PROJECTBASEDIR%" %WRAPPER_LAUNCHER% %MAVEN_CONFIG% %*
+if ERRORLEVEL 1 goto error
+goto end
+
+:error
+set ERROR_CODE=1
+
+:end
+@endlocal & set ERROR_CODE=%ERROR_CODE%
+
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPost
+@REM check for post script, once with legacy .bat ending and once with .cmd ending
+if exist "%HOME%\mavenrc_post.bat" call "%HOME%\mavenrc_post.bat"
+if exist "%HOME%\mavenrc_post.cmd" call "%HOME%\mavenrc_post.cmd"
+:skipRcPost
+
+@REM pause the script if MAVEN_BATCH_PAUSE is set to 'on'
+if "%MAVEN_BATCH_PAUSE%" == "on" pause
+
+if "%MAVEN_TERMINATE_CMD%" == "on" exit %ERROR_CODE%
+
+exit /B %ERROR_CODE%

monitoring-samples/stream-apps/demo-source/pom.xml

@@ -0,0 +1,82 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<parent>
+		<groupId>org.springframework.boot</groupId>
+		<artifactId>spring-boot-starter-parent</artifactId>
+		<version>2.1.8.RELEASE</version>
+		<relativePath/> <!-- lookup parent from repository -->
+	</parent>
+	<groupId>com.example</groupId>
+	<artifactId>demo-source</artifactId>
+	<version>0.0.1-SNAPSHOT</version>
+	<name>demo-source</name>
+	<description>Demo project for Spring Boot</description>
+
+	<properties>
+		<java.version>1.8</java.version>
+		<spring-cloud.version>Greenwich.SR3</spring-cloud.version>
+	</properties>
+
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework.cloud</groupId>
+			<artifactId>spring-cloud-stream</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.cloud</groupId>
+			<artifactId>spring-cloud-starter-stream-rabbit</artifactId>
+		</dependency>
+
+
+		<dependency>
+			<groupId>org.springframework.cloud.stream.app</groupId>
+			<artifactId>app-starters-micrometer-common</artifactId>
+			<version>2.1.2.RELEASE</version>
+		</dependency>
+		<dependency>
+			<groupId>io.micrometer</groupId>
+			<artifactId>micrometer-registry-prometheus</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>io.micrometer.prometheus</groupId>
+			<artifactId>prometheus-rsocket-spring</artifactId>
+			<version>0.9.0</version>
+		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.cloud</groupId>
+			<artifactId>spring-cloud-stream-test-support</artifactId>
+			<scope>test</scope>
+		</dependency>
+	</dependencies>
+
+	<dependencyManagement>
+		<dependencies>
+			<dependency>
+				<groupId>org.springframework.cloud</groupId>
+				<artifactId>spring-cloud-dependencies</artifactId>
+				<version>${spring-cloud.version}</version>
+				<type>pom</type>
+				<scope>import</scope>
+			</dependency>
+		</dependencies>
+	</dependencyManagement>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.springframework.boot</groupId>
+				<artifactId>spring-boot-maven-plugin</artifactId>
+			</plugin>
+		</plugins>
+	</build>
+</project>

monitoring-samples/stream-apps/demo-source/src/main/java/com/example/demosource/DemoSourceApplication.java

@@ -0,0 +1,31 @@
+package com.example.demosource;
+
+import java.util.Date;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.cloud.stream.annotation.EnableBinding;
+import org.springframework.cloud.stream.messaging.Source;
+import org.springframework.messaging.support.MessageBuilder;
+import org.springframework.scheduling.annotation.EnableScheduling;
+import org.springframework.scheduling.annotation.Scheduled;
+
+@EnableScheduling
+@EnableBinding(Source.class)
+@SpringBootApplication
+public class DemoSourceApplication {
+
+	@Autowired
+	private Source source;
+
+	@Scheduled(fixedDelay = 1000)
+	public void sendGreetingEvents() {
+		this.source.output().send(MessageBuilder.withPayload("Greeting: " + new Date().toString()).build());
+	}
+
+	public static void main(String[] args) {
+		SpringApplication.run(DemoSourceApplication.class, args);
+	}
+
+}

monitoring-samples/stream-apps/demo-source/src/main/resources/application.properties

@@ -0,0 +1 @@
+

monitoring-samples/stream-apps/demo-source/src/test/java/com/example/demosource/DemoSourceApplicationTests.java

@@ -0,0 +1,17 @@
+package com.example.demosource;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.junit4.SpringRunner;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest
+public class DemoSourceApplicationTests {
+
+	@Test
+	public void contextLoads() {
+	}
+
+}

monitoring-samples/task-apps/task-demo-metrics-influxdb/.gitignore

@@ -0,0 +1,31 @@
+HELP.md
+target/
+!.mvn/wrapper/maven-wrapper.jar
+!**/src/main/**
+!**/src/test/**
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+build/
+
+### VS Code ###
+.vscode/

monitoring-samples/task-apps/task-demo-metrics-influxdb/.mvn/wrapper/maven-wrapper.properties

@@ -0,0 +1 @@
+distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.6.0/apache-maven-3.6.0-bin.zip

monitoring-samples/task-apps/task-demo-metrics-influxdb/mvnw.cmd

@@ -0,0 +1,161 @@
+@REM ----------------------------------------------------------------------------
+@REM Licensed to the Apache Software Foundation (ASF) under one
+@REM or more contributor license agreements.  See the NOTICE file
+@REM distributed with this work for additional information
+@REM regarding copyright ownership.  The ASF licenses this file
+@REM to you under the Apache License, Version 2.0 (the
+@REM "License"); you may not use this file except in compliance
+@REM with the License.  You may obtain a copy of the License at
+@REM
+@REM    https://www.apache.org/licenses/LICENSE-2.0
+@REM
+@REM Unless required by applicable law or agreed to in writing,
+@REM software distributed under the License is distributed on an
+@REM "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+@REM KIND, either express or implied.  See the License for the
+@REM specific language governing permissions and limitations
+@REM under the License.
+@REM ----------------------------------------------------------------------------
+
+@REM ----------------------------------------------------------------------------
+@REM Maven2 Start Up Batch script
+@REM
+@REM Required ENV vars:
+@REM JAVA_HOME - location of a JDK home dir
+@REM
+@REM Optional ENV vars
+@REM M2_HOME - location of maven2's installed home dir
+@REM MAVEN_BATCH_ECHO - set to 'on' to enable the echoing of the batch commands
+@REM MAVEN_BATCH_PAUSE - set to 'on' to wait for a key stroke before ending
+@REM MAVEN_OPTS - parameters passed to the Java VM when running Maven
+@REM     e.g. to debug Maven itself, use
+@REM set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+@REM MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+@REM ----------------------------------------------------------------------------
+
+@REM Begin all REM lines with '@' in case MAVEN_BATCH_ECHO is 'on'
+@echo off
+@REM set title of command window
+title %0
+@REM enable echoing my setting MAVEN_BATCH_ECHO to 'on'
+@if "%MAVEN_BATCH_ECHO%" == "on"  echo %MAVEN_BATCH_ECHO%
+
+@REM set %HOME% to equivalent of $HOME
+if "%HOME%" == "" (set "HOME=%HOMEDRIVE%%HOMEPATH%")
+
+@REM Execute a user defined script before this one
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPre
+@REM check for pre script, once with legacy .bat ending and once with .cmd ending
+if exist "%HOME%\mavenrc_pre.bat" call "%HOME%\mavenrc_pre.bat"
+if exist "%HOME%\mavenrc_pre.cmd" call "%HOME%\mavenrc_pre.cmd"
+:skipRcPre
+
+@setlocal
+
+set ERROR_CODE=0
+
+@REM To isolate internal variables from possible post scripts, we use another setlocal
+@setlocal
+
+@REM ==== START VALIDATION ====
+if not "%JAVA_HOME%" == "" goto OkJHome
+
+echo.
+echo Error: JAVA_HOME not found in your environment. >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+:OkJHome
+if exist "%JAVA_HOME%\bin\java.exe" goto init
+
+echo.
+echo Error: JAVA_HOME is set to an invalid directory. >&2
+echo JAVA_HOME = "%JAVA_HOME%" >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+@REM ==== END VALIDATION ====
+
+:init
+
+@REM Find the project base dir, i.e. the directory that contains the folder ".mvn".
+@REM Fallback to current working directory if not found.
+
+set MAVEN_PROJECTBASEDIR=%MAVEN_BASEDIR%
+IF NOT "%MAVEN_PROJECTBASEDIR%"=="" goto endDetectBaseDir
+
+set EXEC_DIR=%CD%
+set WDIR=%EXEC_DIR%
+:findBaseDir
+IF EXIST "%WDIR%"\.mvn goto baseDirFound
+cd ..
+IF "%WDIR%"=="%CD%" goto baseDirNotFound
+set WDIR=%CD%
+goto findBaseDir
+
+:baseDirFound
+set MAVEN_PROJECTBASEDIR=%WDIR%
+cd "%EXEC_DIR%"
+goto endDetectBaseDir
+
+:baseDirNotFound
+set MAVEN_PROJECTBASEDIR=%EXEC_DIR%
+cd "%EXEC_DIR%"
+
+:endDetectBaseDir
+
+IF NOT EXIST "%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config" goto endReadAdditionalConfig
+
+@setlocal EnableExtensions EnableDelayedExpansion
+for /F "usebackq delims=" %%a in ("%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config") do set JVM_CONFIG_MAVEN_PROPS=!JVM_CONFIG_MAVEN_PROPS! %%a
+@endlocal & set JVM_CONFIG_MAVEN_PROPS=%JVM_CONFIG_MAVEN_PROPS%
+
+:endReadAdditionalConfig
+
+SET MAVEN_JAVA_EXE="%JAVA_HOME%\bin\java.exe"
+set WRAPPER_JAR="%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.jar"
+set WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+set DOWNLOAD_URL="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.4.2/maven-wrapper-0.4.2.jar"
+FOR /F "tokens=1,2 delims==" %%A IN (%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.properties) DO (
+	IF "%%A"=="wrapperUrl" SET DOWNLOAD_URL=%%B 
+)
+
+@REM Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+@REM This allows using the maven wrapper in projects that prohibit checking in binary data.
+if exist %WRAPPER_JAR% (
+    echo Found %WRAPPER_JAR%
+) else (
+    echo Couldn't find %WRAPPER_JAR%, downloading it ...
+	echo Downloading from: %DOWNLOAD_URL%
+    powershell -Command "(New-Object Net.WebClient).DownloadFile('%DOWNLOAD_URL%', '%WRAPPER_JAR%')"
+    echo Finished downloading %WRAPPER_JAR%
+)
+@REM End of extension
+
+%MAVEN_JAVA_EXE% %JVM_CONFIG_MAVEN_PROPS% %MAVEN_OPTS% %MAVEN_DEBUG_OPTS% -classpath %WRAPPER_JAR% "-Dmaven.multiModuleProjectDirectory=%MAVEN_PROJECTBASEDIR%" %WRAPPER_LAUNCHER% %MAVEN_CONFIG% %*
+if ERRORLEVEL 1 goto error
+goto end
+
+:error
+set ERROR_CODE=1
+
+:end
+@endlocal & set ERROR_CODE=%ERROR_CODE%
+
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPost
+@REM check for post script, once with legacy .bat ending and once with .cmd ending
+if exist "%HOME%\mavenrc_post.bat" call "%HOME%\mavenrc_post.bat"
+if exist "%HOME%\mavenrc_post.cmd" call "%HOME%\mavenrc_post.cmd"
+:skipRcPost
+
+@REM pause the script if MAVEN_BATCH_PAUSE is set to 'on'
+if "%MAVEN_BATCH_PAUSE%" == "on" pause
+
+if "%MAVEN_TERMINATE_CMD%" == "on" exit %ERROR_CODE%
+
+exit /B %ERROR_CODE%

monitoring-samples/task-apps/task-demo-metrics-prometheus/.gitignore

@@ -0,0 +1,31 @@
+HELP.md
+target/
+!.mvn/wrapper/maven-wrapper.jar
+!**/src/main/**
+!**/src/test/**
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+build/
+
+### VS Code ###
+.vscode/

monitoring-samples/task-apps/task-demo-metrics-prometheus/.mvn/wrapper/maven-wrapper.properties

@@ -0,0 +1 @@
+distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.6.0/apache-maven-3.6.0-bin.zip

monitoring-samples/task-apps/task-demo-metrics-prometheus/mvnw.cmd

@@ -0,0 +1,161 @@
+@REM ----------------------------------------------------------------------------
+@REM Licensed to the Apache Software Foundation (ASF) under one
+@REM or more contributor license agreements.  See the NOTICE file
+@REM distributed with this work for additional information
+@REM regarding copyright ownership.  The ASF licenses this file
+@REM to you under the Apache License, Version 2.0 (the
+@REM "License"); you may not use this file except in compliance
+@REM with the License.  You may obtain a copy of the License at
+@REM
+@REM    https://www.apache.org/licenses/LICENSE-2.0
+@REM
+@REM Unless required by applicable law or agreed to in writing,
+@REM software distributed under the License is distributed on an
+@REM "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+@REM KIND, either express or implied.  See the License for the
+@REM specific language governing permissions and limitations
+@REM under the License.
+@REM ----------------------------------------------------------------------------
+
+@REM ----------------------------------------------------------------------------
+@REM Maven2 Start Up Batch script
+@REM
+@REM Required ENV vars:
+@REM JAVA_HOME - location of a JDK home dir
+@REM
+@REM Optional ENV vars
+@REM M2_HOME - location of maven2's installed home dir
+@REM MAVEN_BATCH_ECHO - set to 'on' to enable the echoing of the batch commands
+@REM MAVEN_BATCH_PAUSE - set to 'on' to wait for a key stroke before ending
+@REM MAVEN_OPTS - parameters passed to the Java VM when running Maven
+@REM     e.g. to debug Maven itself, use
+@REM set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+@REM MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+@REM ----------------------------------------------------------------------------
+
+@REM Begin all REM lines with '@' in case MAVEN_BATCH_ECHO is 'on'
+@echo off
+@REM set title of command window
+title %0
+@REM enable echoing my setting MAVEN_BATCH_ECHO to 'on'
+@if "%MAVEN_BATCH_ECHO%" == "on"  echo %MAVEN_BATCH_ECHO%
+
+@REM set %HOME% to equivalent of $HOME
+if "%HOME%" == "" (set "HOME=%HOMEDRIVE%%HOMEPATH%")
+
+@REM Execute a user defined script before this one
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPre
+@REM check for pre script, once with legacy .bat ending and once with .cmd ending
+if exist "%HOME%\mavenrc_pre.bat" call "%HOME%\mavenrc_pre.bat"
+if exist "%HOME%\mavenrc_pre.cmd" call "%HOME%\mavenrc_pre.cmd"
+:skipRcPre
+
+@setlocal
+
+set ERROR_CODE=0
+
+@REM To isolate internal variables from possible post scripts, we use another setlocal
+@setlocal
+
+@REM ==== START VALIDATION ====
+if not "%JAVA_HOME%" == "" goto OkJHome
+
+echo.
+echo Error: JAVA_HOME not found in your environment. >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+:OkJHome
+if exist "%JAVA_HOME%\bin\java.exe" goto init
+
+echo.
+echo Error: JAVA_HOME is set to an invalid directory. >&2
+echo JAVA_HOME = "%JAVA_HOME%" >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+@REM ==== END VALIDATION ====
+
+:init
+
+@REM Find the project base dir, i.e. the directory that contains the folder ".mvn".
+@REM Fallback to current working directory if not found.
+
+set MAVEN_PROJECTBASEDIR=%MAVEN_BASEDIR%
+IF NOT "%MAVEN_PROJECTBASEDIR%"=="" goto endDetectBaseDir
+
+set EXEC_DIR=%CD%
+set WDIR=%EXEC_DIR%
+:findBaseDir
+IF EXIST "%WDIR%"\.mvn goto baseDirFound
+cd ..
+IF "%WDIR%"=="%CD%" goto baseDirNotFound
+set WDIR=%CD%
+goto findBaseDir
+
+:baseDirFound
+set MAVEN_PROJECTBASEDIR=%WDIR%
+cd "%EXEC_DIR%"
+goto endDetectBaseDir
+
+:baseDirNotFound
+set MAVEN_PROJECTBASEDIR=%EXEC_DIR%
+cd "%EXEC_DIR%"
+
+:endDetectBaseDir
+
+IF NOT EXIST "%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config" goto endReadAdditionalConfig
+
+@setlocal EnableExtensions EnableDelayedExpansion
+for /F "usebackq delims=" %%a in ("%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config") do set JVM_CONFIG_MAVEN_PROPS=!JVM_CONFIG_MAVEN_PROPS! %%a
+@endlocal & set JVM_CONFIG_MAVEN_PROPS=%JVM_CONFIG_MAVEN_PROPS%
+
+:endReadAdditionalConfig
+
+SET MAVEN_JAVA_EXE="%JAVA_HOME%\bin\java.exe"
+set WRAPPER_JAR="%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.jar"
+set WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+set DOWNLOAD_URL="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.4.2/maven-wrapper-0.4.2.jar"
+FOR /F "tokens=1,2 delims==" %%A IN (%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.properties) DO (
+	IF "%%A"=="wrapperUrl" SET DOWNLOAD_URL=%%B 
+)
+
+@REM Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+@REM This allows using the maven wrapper in projects that prohibit checking in binary data.
+if exist %WRAPPER_JAR% (
+    echo Found %WRAPPER_JAR%
+) else (
+    echo Couldn't find %WRAPPER_JAR%, downloading it ...
+	echo Downloading from: %DOWNLOAD_URL%
+    powershell -Command "(New-Object Net.WebClient).DownloadFile('%DOWNLOAD_URL%', '%WRAPPER_JAR%')"
+    echo Finished downloading %WRAPPER_JAR%
+)
+@REM End of extension
+
+%MAVEN_JAVA_EXE% %JVM_CONFIG_MAVEN_PROPS% %MAVEN_OPTS% %MAVEN_DEBUG_OPTS% -classpath %WRAPPER_JAR% "-Dmaven.multiModuleProjectDirectory=%MAVEN_PROJECTBASEDIR%" %WRAPPER_LAUNCHER% %MAVEN_CONFIG% %*
+if ERRORLEVEL 1 goto error
+goto end
+
+:error
+set ERROR_CODE=1
+
+:end
+@endlocal & set ERROR_CODE=%ERROR_CODE%
+
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPost
+@REM check for post script, once with legacy .bat ending and once with .cmd ending
+if exist "%HOME%\mavenrc_post.bat" call "%HOME%\mavenrc_post.bat"
+if exist "%HOME%\mavenrc_post.cmd" call "%HOME%\mavenrc_post.cmd"
+:skipRcPost
+
+@REM pause the script if MAVEN_BATCH_PAUSE is set to 'on'
+if "%MAVEN_BATCH_PAUSE%" == "on" pause
+
+if "%MAVEN_TERMINATE_CMD%" == "on" exit %ERROR_CODE%
+
+exit /B %ERROR_CODE%

monitoring-samples/task-apps/task-demo-metrics-prometheus/pom.xml

@@ -18,7 +18,7 @@
 		<java.version>1.8</java.version>
 		<spring-cloud.version>Hoxton.M2</spring-cloud.version>
 		<spring-cloud-task.version>2.2.0.M2</spring-cloud-task.version>
-		<prometheus-rsocket-spring.version>0.8.0</prometheus-rsocket-spring.version>
+		<prometheus-rsocket-spring.version>0.9.0</prometheus-rsocket-spring.version>
 	</properties>
 
 	<dependencies>