Sample using Event Hub Log4j Appender (#482)

* sample added for Log4j Event Hub appender

* updated ReadME

* updated files

samples/Java/Basic/Log4jAppenderSample/README.md

@@ -0,0 +1,14 @@
+# EventHub Appender Java Sample
+
+This sample demonstrates the use of EventHubAppender for streaming/sending log4j2 logs to Azure Event Hub.
+The EventHubAppender extension (Log4j plugin) code can be found at https://github.com/Azure/azure-sdk-for-java/tree/main/sdk/eventhubs/microsoft-azure-eventhubs-extensions
+
+Note : The above extension depends on [this version of Azure Event Hubs library](https://github.com/Azure/azure-sdk-for-java/tree/main/sdk/eventhubs/microsoft-azure-eventhubs).
+
+Steps to run the project :
+  1. Clone the repository.
+  2. Update the value of 'eventHubConnectionString' in src/main/resources/log4j2.xml file. (This is the config file)
+  3. Update the value of 'classpathPrefix' element in the pom.xml file of the project
+  4. Run 'mvn clean'
+  5. Run 'mvn package'
+  6. Run 'java -cp target/my-app-1.0-SNAPSHOT.jar:<classpath-to-jar-dependencies>/*:  com.eventhubappendersample.app.App'

samples/Java/Basic/Log4jAppenderSample/pom.xml

@@ -0,0 +1,74 @@
+<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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <groupId>log4jeventhubappendersample</groupId>
+  <artifactId>log4jeventhubappendersample</artifactId>
+  <packaging>jar</packaging>
+  <version>1.0.0</version>
+  <properties>
+    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+  </properties>
+  <dependencies>
+		<dependency>
+                        <groupId>org.apache.logging.log4j</groupId>
+                        <artifactId>log4j-api</artifactId>
+                        <version>2.13.0</version>
+                </dependency>
+		<dependency>
+                        <groupId>org.apache.logging.log4j</groupId>
+                        <artifactId>log4j-core</artifactId>
+                        <version>[2.13.2,)</version>
+		</dependency>
+		<dependency>
+	 		<groupId>com.microsoft.azure</groupId>
+  			<artifactId>azure-eventhubs-extensions</artifactId>
+ 			<version>3.3.0</version>
+  		</dependency>
+	  	<dependency>
+                        <groupId>org.slf4j</groupId>
+                        <artifactId>slf4j-api</artifactId>
+                        <version>1.7.32</version>
+                </dependency>
+
+                <dependency>
+                        <groupId>org.slf4j</groupId>
+                        <artifactId>slf4j-simple</artifactId>
+                        <version>1.7.32</version>
+                </dependency>
+	</dependencies>
+  <build>
+      <plugins>
+
+	<plugin>
+          <artifactId>maven-compiler-plugin</artifactId>
+	  <version>3.8.0</version>
+	    <configuration>
+                    <source>1.8</source>
+                    <target>1.8</target>
+                    <debug>true</debug>
+                    <debuglevel>lines,vars,source</debuglevel>
+                </configuration>
+        </plugin>
+         <plugin>
+                <artifactId>maven-assembly-plugin</artifactId>
+                <executions>
+                    <execution>
+                        <phase>package</phase>
+                        <goals>
+                            <goal>single</goal>
+                        </goals>
+                    </execution>
+                </executions>
+                <configuration>
+                    <descriptorRefs>
+                        <descriptorRef>jar-with-dependencies</descriptorRef>
+                    </descriptorRefs>
+                    <archive>
+                        <manifest>
+                            <mainClass>com.microsoft.azure.eventhubs.samples.log4jeventhubappendersample.Log4JEventHubAppenderSample</mainClass>
+                        </manifest>
+                    </archive>
+                </configuration>
+            </plugin>	
+      </plugins>
+  </build>
+</project>

samples/Java/Basic/Log4jAppenderSample/src/main/java/com/microsoft/azure/eventhubs/samples/log4jeventhubappendersample/Log4JEventHubAppenderSample.java

@@ -0,0 +1,29 @@
+package com.microsoft.azure.eventhubs.samples.log4jeventhubappendersample;
+
+import java.util.concurrent.TimeUnit;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+
+/**
+ * Hello world!
+ *
+ */
+public class Log4JEventHubAppenderSample
+{
+    private static final Logger logger = LogManager.getLogger(Log4JEventHubAppenderSample.class);
+    public static void main( String[] args )
+    {
+        int i;
+                for(i=0; i<=10;i++)
+                {
+                        try {
+                        TimeUnit.SECONDS.sleep(1);
+                        logger.error("Hello World " + i);
+                        }
+
+                        catch(InterruptedException e)
+                        {
+                        }
+                }
+    }
+}

samples/Java/Basic/Log4jAppenderSample/src/main/resources/log4j2.xml

@@ -0,0 +1,22 @@
+<?xml version="1.0" encoding="UTF-8"?>
+    <Configuration status="all" packages="com.microsoft.azure.eventhubs.extensions.appender">
+	<Appenders>
+		<EventHub name="EventHub" ignoreExceptions="false" eventHubConnectionString="--event-hub-connection-string" immediateFlush="true">
+	    		<JSONLayout />
+		</EventHub>
+
+     		<Console name="console" target="SYSTEM_OUT">
+            		<PatternLayout pattern="%msg%n" />
+    		</Console>
+
+
+	</Appenders>
+
+    	<Loggers>
+       		 <Root level="all">
+			<appender-ref ref="console" />
+			<appender-ref ref="EventHub" />
+		</Root>
+
+      </Loggers>
+    </Configuration>

samples/Java/pom.xml

@@ -30,7 +30,8 @@
         <module>Basic/SendBatch</module>
         <module>Basic/SimpleSend</module>
         <module>Basic/AsyncSend</module>
-        <module>Basic/SimpleProxy</module>
+	<module>Basic/SimpleProxy</module>
+	<module>Basic/Log4jAppenderSample</module>
         <module>Benchmarks/AutoScaleOnIngress</module>
         <module>Benchmarks/IngressBenchmark</module>
     </modules>