Configure log explicitly with custom configuration file

Jetty (used in Prometheus support) is verbose when starting, so the
default Logback configuration isn't used anymore. As PerfTest cannot
embed a logback.xml file at the root of the classpath, a custom file is
provided and used explicitly. This can be overriden by using the
logback.configurationFile system property.

[#158209647]

References #42

Author: acogoluegnes

pom.xml

@@ -121,6 +121,19 @@
       <artifactId>micrometer-registry-prometheus</artifactId>
       <version>${micrometer.version}</version>
     </dependency>
+    <dependency>
+      <groupId>ch.qos.logback</groupId>
+      <artifactId>logback-classic</artifactId>
+      <version>${logback.version}</version>
+      <optional>true</optional>
+    </dependency>
+    <dependency>
+      <groupId>ch.qos.logback</groupId>
+      <artifactId>logback-core</artifactId>
+      <version>${logback.version}</version>
+      <optional>true</optional>
+    </dependency>
+
 
     <dependency>
       <groupId>org.junit.jupiter</groupId>
@@ -179,13 +192,6 @@
       <scope>test</scope>
     </dependency>
 
-    <dependency>
-      <groupId>ch.qos.logback</groupId>
-      <artifactId>logback-classic</artifactId>
-      <version>${logback.version}</version>
-      <scope>test</scope>
-    </dependency>
-
     <dependency>
       <groupId>org.openjdk.jmh</groupId>
       <artifactId>jmh-core</artifactId>
@@ -464,6 +470,12 @@
           <version>${logback.version}</version>
         </dependency>
 
+        <dependency>
+          <groupId>ch.qos.logback</groupId>
+          <artifactId>logback-core</artifactId>
+          <version>${logback.version}</version>
+        </dependency>
+
       </dependencies>
       <build>
         <plugins>

src/main/java/com/rabbitmq/perf/PerfTest.java

@@ -30,6 +30,10 @@
 import java.util.concurrent.TimeUnit;
 import java.util.function.Function;
 
+import ch.qos.logback.classic.LoggerContext;
+import ch.qos.logback.classic.joran.JoranConfigurator;
+import ch.qos.logback.core.joran.spi.JoranException;
+import ch.qos.logback.core.util.StatusPrinter;
 import com.rabbitmq.client.impl.ClientVersion;
 import com.rabbitmq.client.impl.nio.NioParams;
 import io.micrometer.core.instrument.MeterRegistry;
@@ -340,10 +344,29 @@ static MulticastSet.CompletionHandler getCompletionHandler(MulticastParams p) {
         return completionHandler;
     }
 
-    public static void main(String[] args) {
+    public static void main(String[] args) throws IOException {
+        configureLogbackIfNecessary();
         main(args, new PerfTestOptions().setSystemExiter(new JvmSystemExiter()).setSkipSslContextConfiguration(false));
     }
 
+    private static void configureLogbackIfNecessary() throws IOException {
+        if (System.getProperty("logback.configurationFile") == null) {
+            LoggerContext context = (LoggerContext) LoggerFactory.getILoggerFactory();
+            InputStream configurationFile = PerfTest.class.getResourceAsStream("/logback-perf-test.xml");
+            try {
+                JoranConfigurator configurator = new JoranConfigurator();
+                configurator.setContext(context);
+                context.reset();
+                configurator.doConfigure(configurationFile);
+            } catch (JoranException je) {
+                // StatusPrinter will handle this
+            } finally {
+                configurationFile.close();
+            }
+            StatusPrinter.printInCaseOfErrorsOrWarnings(context);
+        }
+    }
+
     private static SSLContext getSslContextIfNecessary(CommandLineProxy cmd, Properties systemProperties) throws NoSuchAlgorithmException {
         SSLContext sslContext = null;
         if (hasOption(cmd, "udsc") || hasOption(cmd,"useDefaultSslContext")) {