Add rabbitmq test

core/src/main/java/io/jstach/rainbowgum/ConfigObject.java

@@ -17,9 +17,10 @@
 
 	/**
 	 * Name of builder.
-	 * @return name of builder.
+	 * @return name of builder by default if not set Builder will be suffixed to
+	 * targetType.
 	 */
-	String name();
+	String name() default "";
 
 	/**
 	 * Property prefix.
@@ -43,4 +44,21 @@
 
 	}
 
+	/**
+	 * Use to set static defaults to parameters.
+	 */
+	@Retention(CLASS)
+	@Target({ ElementType.PARAMETER })
+	@Documented
+	public @interface DefaultParameter {
+
+		/**
+		 * Use as parameter to prefix property names.
+		 * @return by default will use the static field
+		 * <code>DEFAULT_parameterName</code>.
+		 */
+		String value() default "";
+
+	}
+
 }

core/src/main/java/io/jstach/rainbowgum/LogAppender.java

@@ -15,7 +15,7 @@
  *
  * The only exception is if an Appender implements {@link ThreadSafeLogAppender}.
  */
-public interface LogAppender extends AutoCloseable, LogEventConsumer {
+public interface LogAppender extends LogLifecycle, LogEventConsumer {
 
 	/**
 	 * Batch of events. <strong>DO NOT MODIFY THE ARRAY</strong>. Do not use the
@@ -221,6 +221,11 @@ protected void append(LogEvent[] events, int count, Buffer buffer) {
 
 		protected abstract void append(LogEvent event, Buffer buffer);
 
+		@Override
+		public void start(LogConfig config) {
+			output.start(config);
+		}
+
 		@Override
 		public void close() {
 			output.close();
@@ -252,6 +257,13 @@ public void close() {
 		}
 	}
 
+	@Override
+	public void start(LogConfig config) {
+		for (var appender : appenders) {
+			appender.start(config);
+		}
+	}
+
 }
 
 class LockingLogAppender implements ThreadSafeLogAppender {
@@ -288,6 +300,11 @@ public void append(LogEvent event) {
 
 	}
 
+	@Override
+	public void start(LogConfig config) {
+		appender.start(config);
+	}
+
 	@Override
 	public void close() {
 		appender.close();

core/src/main/java/io/jstach/rainbowgum/LogConfig.java

@@ -6,6 +6,8 @@
 import java.util.concurrent.CopyOnWriteArrayList;
 import java.util.function.Consumer;
 
+import org.eclipse.jdt.annotation.Nullable;
+
 import io.jstach.rainbowgum.LevelResolver.LevelConfig;
 import io.jstach.rainbowgum.LogConfig.ChangePublisher;
 import io.jstach.rainbowgum.LogProperties.Property;
@@ -81,6 +83,14 @@ public static LogConfig of(ServiceRegistry registry, LogProperties properties) {
 		return new DefaultLogConfig(registry, properties);
 	}
 
+	/**
+	 * Creates a builder for making LogConfig.
+	 * @return builder.
+	 */
+	public static Builder builder() {
+		return new Builder();
+	}
+
 	/**
 	 * An event publisher to publish configuration changes.
 	 * @return publisher.
@@ -119,6 +129,59 @@ interface ChangePublisher {
 
 	}
 
+	/**
+	 * Builder for LogConfig.
+	 */
+	public static final class Builder {
+
+		private @Nullable ServiceRegistry serviceRegistry;
+
+		private @Nullable LogProperties logProperties;
+
+		/**
+		 * Default constructor
+		 */
+		private Builder() {
+		}
+
+		/**
+		 * Sets log properties
+		 * @param logProperties log properties.
+		 * @return this.
+		 */
+		public Builder logProperties(LogProperties logProperties) {
+			this.logProperties = logProperties;
+			return this;
+		}
+
+		/**
+		 * Sets service registry
+		 * @param serviceRegistry service registry.
+		 * @return this.
+		 */
+		public Builder serviceRegistry(ServiceRegistry serviceRegistry) {
+			this.serviceRegistry = serviceRegistry;
+			return this;
+		}
+
+		/**
+		 * Builds LogConfig using defaults on missing properties.
+		 * @return log config
+		 */
+		public LogConfig build() {
+			ServiceRegistry serviceRegistry = this.serviceRegistry;
+			LogProperties logProperties = this.logProperties;
+			if (serviceRegistry == null) {
+				serviceRegistry = ServiceRegistry.of();
+			}
+			if (logProperties == null) {
+				logProperties = LogProperties.StandardProperties.SYSTEM_PROPERTIES;
+			}
+			return LogConfig.of(serviceRegistry, logProperties);
+		}
+
+	}
+
 }
 
 abstract class AbstractChangePublisher implements ChangePublisher {

core/src/main/java/io/jstach/rainbowgum/LogPublisher.java

@@ -140,11 +140,6 @@ public static SyncLogPublisher.Builder builder() {
 			return new Builder();
 		}
 
-		@Override
-		default void start(LogConfig config) {
-
-		}
-
 		default boolean synchronous() {
 			return true;
 		}
@@ -195,6 +190,11 @@ public void log(LogEvent event) {
 		appender.append(event);
 	}
 
+	@Override
+	public void start(LogConfig config) {
+		appender.start(config);
+	}
+
 	@Override
 	public void close() {
 		appender.close();

core/src/main/java/io/jstach/rainbowgum/LogRouter.java

@@ -459,6 +459,10 @@ public void append(LogEvent event) {
 	public void close() {
 	}
 
+	@Override
+	public void start(LogConfig config) {
+	}
+
 }
 
 enum GlobalLogRouter implements InternalRootRouter, Route {

core/src/main/java/io/jstach/rainbowgum/RainbowGum.java

@@ -24,7 +24,7 @@
  * <p>
  * To register a custom RainbowGum:
  *
- * 
+ *
 {@snippet class="snippets.RainbowGumProviderExample" region="provider" :
 
 class RainbowGumProviderExample implements RainbowGumProvider {
@@ -208,6 +208,10 @@ static RainbowGum get() {
 		finally {
 			lock.readLock().unlock();
 		}
+		if (lock.writeLock().isHeldByCurrentThread()) {
+			throw new IllegalStateException("RainbowGum component tried to log too early. "
+					+ "This is usually caused by dependencies calling logging.");
+		}
 		lock.writeLock().lock();
 		try {
 			var r = rainbowGum;
@@ -228,6 +232,10 @@ static RainbowGum get() {
 
 	static void set(Supplier<RainbowGum> rainbowGumSupplier) {
 		Objects.requireNonNull(rainbowGumSupplier);
+		if (lock.writeLock().isHeldByCurrentThread()) {
+			throw new IllegalStateException("RainbowGum component tried to log too early. "
+					+ "This is usually caused by dependencies calling logging.");
+		}
 		lock.writeLock().lock();
 		try {
 			rainbowGum = null;

core/src/main/java/io/jstach/rainbowgum/appender/SynchronizedLogAppender.java

@@ -5,6 +5,7 @@
 import io.jstach.rainbowgum.LogAppender;
 import io.jstach.rainbowgum.LogAppender.AbstractLogAppender;
 import io.jstach.rainbowgum.LogAppender.ThreadSafeLogAppender;
+import io.jstach.rainbowgum.LogConfig;
 import io.jstach.rainbowgum.LogEncoder;
 import io.jstach.rainbowgum.LogEncoder.Buffer;
 import io.jstach.rainbowgum.LogEvent;
@@ -60,6 +61,11 @@ public synchronized void append(LogEvent event) {
 		appender.append(event);
 	}
 
+	@Override
+	public void start(LogConfig config) {
+		appender.start(config);
+	}
+
 	@Override
 	public void close() {
 		appender.close();

core/src/main/java/io/jstach/rainbowgum/spi/RainbowGumServiceProvider.java

@@ -118,9 +118,13 @@ private static LogConfig provideConfig(ServiceLoader<RainbowGumServiceProvider>
 			.orElseGet(() -> LogConfig.of(registry, properties));
 	}
 
-	private static void runInitializers(ServiceLoader<RainbowGumServiceProvider> loader, ServiceRegistry registry,
-			LogConfig config) {
-		findProviders(loader, Initializer.class).forEach(c -> c.initialize(registry, config));
+	/**
+	 * Runs initializers based on config.
+	 * @param loader service loader to use.
+	 * @param config config before initializers have run.
+	 */
+	public static void runInitializers(ServiceLoader<RainbowGumServiceProvider> loader, LogConfig config) {
+		findProviders(loader, Initializer.class).forEach(c -> c.initialize(config.registry(), config));
 	}
 
 	/**
@@ -132,7 +136,7 @@ public static LogConfig provideConfig(ServiceLoader<RainbowGumServiceProvider> l
 		ServiceRegistry registry = ServiceRegistry.of();
 		var properties = provideProperties(registry, loader);
 		var config = provideConfig(loader, registry, properties);
-		runInitializers(loader, registry, config);
+		runInitializers(loader, config);
 		return config;
 	}
 

core/src/test/java/io/jstach/rainbowgum/TestSyncPublisher.java

@@ -6,15 +6,19 @@
 import io.jstach.rainbowgum.LogPublisher.SyncLogPublisher;
 
 /**
- * 
+ *
  */
 public class TestSyncPublisher implements SyncLogPublisher {
 
 	/**
-	 * 
+	 *
 	 */
 	public Deque<LogEvent> events = new LinkedList<>();
 
+	@Override
+	public void start(LogConfig config) {
+	}
+
 	@Override
 	public void close() {
 	}

pom.xml

@@ -103,10 +103,15 @@
         <artifactId>rainbowgum-avaje-config</artifactId>
         <version>${project.version}</version>
       </dependency>
-       <dependency>
+      <dependency>
         <groupId>${project.groupId}</groupId>
         <artifactId>rainbowgum-config-apt</artifactId>
         <version>${project.version}</version>
+      </dependency>
+       <dependency>
+        <groupId>${project.groupId}</groupId>
+        <artifactId>rainbowgum-rabbitmq</artifactId>
+        <version>${project.version}</version>
       </dependency>
       <!-- to make dependabot check for latest maven version -->
       <dependency>

rainbowgum-config-apt/src/main/java/io/jstach/rainbowgum/apt/BuilderModel.java

@@ -71,6 +71,13 @@ public String convertMethod() {
 			};
 		}
 
+		boolean isLiteralType() {
+			return switch (type) {
+				case INTEGER_TYPE, STRING_TYPE, BOOLEAN_TYPE -> true;
+				default -> false;
+			};
+		}
+
 		public String valueMethod() {
 			return required ? "value" : "valueOrNull";
 		}
@@ -82,6 +89,27 @@ public boolean isNormal() {
 		public boolean isPrefixParameter() {
 			return kind == PropertyKind.NAME_PARAMETER;
 		}
+
+		public String defaultValueDoc() {
+			if (defaultValue.equals("null")) {
+				return "<code>null</code>";
+			}
+			String link = linkStatic(defaultValue);
+			if (isLiteralType()) {
+				return "{@value " + link + " }";
+			}
+			return "{@link " + link + " }";
+		}
+
+		private static String linkStatic(String constant) {
+			int index = constant.lastIndexOf(".");
+			if (index < 0) {
+				return constant;
+			}
+			StringBuilder sb = new StringBuilder(constant);
+			sb.setCharAt(index, '#');
+			return sb.toString();
+		}
 	}
 
 	enum PropertyKind {