Add registries for components

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

@@ -1,6 +1,5 @@
 package io.jstach.rainbowgum;
 
-import java.net.URI;
 import java.util.List;
 import java.util.concurrent.locks.ReentrantLock;
 import java.util.function.Function;
@@ -20,6 +19,26 @@
  */
 public interface LogAppender extends LogLifecycle, LogEventConsumer {
 
+	/**
+	 * Default Console appender name.
+	 */
+	static final String CONSOLE_APPENDER_NAME = "console";
+
+	/**
+	 * Default output file appender name.
+	 */
+	static final String FILE_APPENDER_NAME = "file";
+
+	/**
+	 * Output appender property.
+	 */
+	static final String APPENDER_OUTPUT_PROPERTY = LogProperties.APPENDER_PREFIX + "output";
+
+	/**
+	 * Encoder appender property.
+	 */
+	static final String APPENDER_ENCODER_PROPERTY = LogProperties.APPENDER_PREFIX + "encoder";
+
 	/**
 	 * Batch of events. <strong>DO NOT MODIFY THE ARRAY</strong>. Do not use the
 	 * <code>length</code> of the passed in array but instead use <code>count</code>
@@ -93,9 +112,19 @@ public static final class Builder {
 
 		protected @Nullable LogEncoder encoder;
 
+		// private final String name;
+
 		private Builder() {
 		}
 
+		//// /**
+		//// * Name of the appender.
+		//// * @return name.
+		//// */
+		//// public String name() {
+		//// return this.name;
+		// }
+
 		/**
 		 * Sets output. If not set defaults to {@link LogOutput#ofStandardOut()}.
 		 * @param output output.
@@ -340,8 +369,6 @@ class DefaultLogAppender extends AbstractLogAppender implements ThreadSafeLogApp
 		return new LockingLogAppender(appender);
 	};
 
-	static final Property<URI> fileProperty = Property.builder().map(URI::new).build(LogProperties.FILE_PROPERTY);
-
 	protected final ReentrantLock lock = new ReentrantLock();
 
 	public DefaultLogAppender(LogOutput output, LogEncoder encoder) {

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

@@ -0,0 +1,142 @@
+package io.jstach.rainbowgum;
+
+import java.net.URI;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+import java.util.Optional;
+import java.util.concurrent.ConcurrentHashMap;
+
+import org.eclipse.jdt.annotation.Nullable;
+
+import io.jstach.rainbowgum.LogAppender.AppenderProvider;
+import io.jstach.rainbowgum.LogProperties.Property;
+
+/**
+ * Register appenders by name.
+ */
+public sealed interface LogAppenderRegistry permits DefaultAppenderRegistry {
+
+	/**
+	 * Finds an appender by name.
+	 * @param name name of the appender.
+	 * @return appender provider to be used for creating the appender.
+	 */
+	Optional<AppenderProvider> appender(String name);
+
+	/**
+	 * Registers an appender provider by name.
+	 * @param name of the appender.
+	 * @param appenderProvider factory to be used for creating appenders.
+	 */
+	void register(String name, AppenderProvider appenderProvider);
+
+	/**
+	 * Creates a log appender registry.
+	 * @return appender registry.
+	 */
+	public static LogAppenderRegistry of() {
+		return new DefaultAppenderRegistry();
+	}
+
+}
+
+final class DefaultAppenderRegistry implements LogAppenderRegistry {
+
+	private final Map<String, AppenderProvider> providers = new ConcurrentHashMap<>();
+
+	static final Property<URI> fileProperty = Property.builder().toURI().build(LogProperties.FILE_PROPERTY);
+
+	static final Property<List<String>> appendersProperty = Property.builder()
+		.map(LogProperties::parseList)
+		.orElse(List.of())
+		.build(LogProperties.APPENDERS_PROPERTY);
+
+	static List<LogAppender> defaultAppenders(LogConfig config) {
+		List<LogAppender> appenders = new ArrayList<>();
+		fileAppender(config).ifPresent(appenders::add);
+		List<String> appenderNames = appendersProperty.get(config.properties()).value(List.of());
+
+		for (String appenderName : appenderNames) {
+			var outputProperty = outputProperty(LogAppender.APPENDER_OUTPUT_PROPERTY, appenderName, config);
+			var encoderProperty = encoderProperty(LogAppender.APPENDER_ENCODER_PROPERTY, appenderName, config);
+			appenders.add(appender(appenderName, outputProperty, encoderProperty, config));
+		}
+		if (appenders.isEmpty()) {
+			var consoleAppender = defaultConsoleAppender(config);
+			appenders.add(consoleAppender);
+		}
+		return appenders;
+	}
+
+	private static LogAppender defaultConsoleAppender(LogConfig config) {
+		var consoleAppender = LogAppender.builder().output(LogOutput.ofStandardOut()).build().provide(config);
+		return consoleAppender;
+	}
+
+	static Optional<LogAppender> fileAppender(LogConfig config) {
+		String name = LogAppender.FILE_APPENDER_NAME;
+		var outputProperty = outputProperty(LogAppender.APPENDER_OUTPUT_PROPERTY, name, config);
+		var encoderProperty = encoderProperty(LogAppender.APPENDER_ENCODER_PROPERTY, name, config);
+		return fileProperty //
+			.map(u -> appender(name, outputProperty, encoderProperty, config))
+			.get(config.properties())
+			.optional();
+	}
+
+	static LogAppender appender( //
+			String name, Property<LogOutput> outputProperty, Property<LogEncoder> encoderProperty, LogConfig config) {
+		var appenderRegistry = config.appenderRegistry();
+		var appender = appenderRegistry.appender(name).map(a -> a.provide(config)).orElse(null);
+		if (appender != null) {
+			return appender;
+		}
+		var builder = LogAppender.builder();
+		LogOutput output = outputProperty.get(config.properties()).valueOrNull();
+		if (output != null) {
+			builder.output(output);
+		}
+		LogEncoder encoder = encoderProperty.get(config.properties()).valueOrNull();
+		if (encoder != null) {
+			builder.encoder(encoder);
+		}
+		return builder.build().provide(config);
+
+	}
+
+	private static @Nullable LogOutput outputForAppender(String propertyName, String name, LogConfig config) {
+		LogOutput output = Property.builder() //
+			.toURI() //
+			.map(u -> config.outputRegistry().output(u, name, config.properties())) //
+			.buildWithName(propertyName, name) //
+			.get(config.properties()) //
+			.valueOrNull();
+		return output;
+	}
+
+	private static Property<LogOutput> outputProperty(String propertyName, String name, LogConfig config) {
+		return Property.builder() //
+			.toURI() //
+			.map(u -> config.outputRegistry().output(u, name, config.properties())) //
+			.buildWithName(propertyName, name);
+	}
+
+	private static Property<LogEncoder> encoderProperty(String propertyName, String name, LogConfig config) {
+		return Property.builder() //
+			.toURI() //
+			.map(u -> config.encoderRegistry().provide(u, name, config.properties())) //
+			.buildWithName(propertyName, name);
+	}
+
+	@Override
+	public Optional<AppenderProvider> appender(String name) {
+		return Optional.ofNullable(providers.get(name));
+	}
+
+	@Override
+	public void register(String name, AppenderProvider appenderProvider) {
+		providers.put(name, appenderProvider);
+
+	}
+
+}

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

@@ -10,9 +10,7 @@
 
 import io.jstach.rainbowgum.LevelResolver.LevelConfig;
 import io.jstach.rainbowgum.LogConfig.ChangePublisher;
-import io.jstach.rainbowgum.LogProperties.Property;
 import io.jstach.rainbowgum.LogProperties.PropertyGetter;
-import io.jstach.rainbowgum.LogProperties.PropertyValue;
 
 /**
  * The configuration of a RainbowGum. In some other logging implementations this is called
@@ -26,16 +24,6 @@ public sealed interface LogConfig {
 	 */
 	public LogProperties properties();
 
-	/**
-	 * Gets a property value from the properties.
-	 * @param <T> property type
-	 * @param property property to look up.
-	 * @return property value nevern <code>null</code>.
-	 */
-	default <T> PropertyValue<T> get(Property<T> property) {
-		return properties().property(property);
-	}
-
 	/**
 	 * Level resolver for resolving levels from logger names.
 	 * @return level resolver.
@@ -54,6 +42,18 @@ default <T> PropertyValue<T> get(Property<T> property) {
 	 */
 	public LogOutputRegistry outputRegistry();
 
+	/**
+	 * Provides appenders by name.
+	 * @return appender registry.
+	 */
+	public LogAppenderRegistry appenderRegistry();
+
+	/**
+	 * Provides encoders by name.
+	 * @return encoder registry.
+	 */
+	public LogEncoderRegistry encoderRegistry();
+
 	/**
 	 * Finds an output from a URI.
 	 * @param uri uri.
@@ -102,7 +102,7 @@ public static Builder builder() {
 	 * initialization process.
 	 * @return registry.
 	 */
-	public ServiceRegistry registry();
+	public ServiceRegistry serviceRegistry();
 
 	/**
 	 * Config Change Publisher.
@@ -230,6 +230,10 @@ final class DefaultLogConfig implements LogConfig {
 
 	private final LogFormatterRegistry formatterRegistry;
 
+	private final LogAppenderRegistry appenderRegistry;
+
+	private final LogEncoderRegistry encoderRegistry;
+
 	public DefaultLogConfig(ServiceRegistry registry, LogProperties properties) {
 		super();
 		this.registry = registry;
@@ -243,6 +247,8 @@ protected LogConfig _config() {
 		};
 		this.outputRegistry = LogOutputRegistry.of();
 		this.formatterRegistry = LogFormatterRegistry.of();
+		this.appenderRegistry = LogAppenderRegistry.of();
+		this.encoderRegistry = LogEncoderRegistry.of();
 	}
 
 	@Override
@@ -256,7 +262,7 @@ public LevelConfig levelResolver() {
 	}
 
 	@Override
-	public ServiceRegistry registry() {
+	public ServiceRegistry serviceRegistry() {
 		return this.registry;
 	}
 
@@ -275,4 +281,14 @@ public LogFormatterRegistry formatterRegistry() {
 		return this.formatterRegistry;
 	}
 
+	@Override
+	public LogAppenderRegistry appenderRegistry() {
+		return this.appenderRegistry;
+	}
+
+	@Override
+	public LogEncoderRegistry encoderRegistry() {
+		return this.encoderRegistry;
+	}
+
 }

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

@@ -1,5 +1,7 @@
 package io.jstach.rainbowgum;
 
+import java.io.IOException;
+import java.net.URI;
 import java.nio.ByteBuffer;
 import java.nio.CharBuffer;
 import java.nio.charset.Charset;
@@ -68,6 +70,23 @@ public static LogEncoder of(LogFormatter formatter) {
 		return new FormatterEncoder(formatter);
 	}
 
+	/**
+	 * Finds output based on URI.
+	 */
+	public interface EncoderProvider {
+
+		/**
+		 * Loads an encoder from a URI.
+		 * @param uri uri.
+		 * @param name name of encoder.
+		 * @param properties key value config.
+		 * @return output.
+		 * @see LogProperties#of(URI)
+		 */
+		LogEncoder provide(URI uri, String name, LogProperties properties);
+
+	}
+
 	/**
 	 * Encoders buffer.
 	 */