Adds minimal logging for bus events.

fixes gh-217

spring-cloud-bus/src/main/java/org/springframework/cloud/bus/BusAutoConfiguration.java

@@ -18,6 +18,9 @@ package org.springframework.cloud.bus;
 
 import javax.annotation.PostConstruct;
 
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.actuate.autoconfigure.endpoint.condition.ConditionalOnAvailableEndpoint;
 import org.springframework.boot.actuate.endpoint.annotation.Endpoint;
@@ -69,6 +72,8 @@ import org.springframework.util.PathMatcher;
 // so actuator endpoints have needed dependencies
 public class BusAutoConfiguration implements ApplicationEventPublisherAware {
 
+	private static final Log log = LogFactory.getLog(BusAutoConfiguration.class);
+
 	/**
 	 * Name of the Bus path matcher.
 	 */
@@ -140,6 +145,9 @@ public class BusAutoConfiguration implements ApplicationEventPublisherAware {
 	public void acceptLocal(RemoteApplicationEvent event) {
 		if (this.serviceMatcher.isFromSelf(event)
 				&& !(event instanceof AckRemoteApplicationEvent)) {
+			if (log.isDebugEnabled()) {
+				log.debug("Sending remote event on bus: " + event);
+			}
 			this.cloudBusOutboundChannel.send(MessageBuilder.withPayload(event).build());
 		}
 	}
@@ -154,6 +162,11 @@ public class BusAutoConfiguration implements ApplicationEventPublisherAware {
 			// If it's an ACK we are finished processing at this point
 			return;
 		}
+
+		if (log.isDebugEnabled()) {
+			log.debug("Received remote event from bus: " + event);
+		}
+
 		if (this.serviceMatcher.isForSelf(event)
 				&& this.applicationEventPublisher != null) {
 			if (!this.serviceMatcher.isFromSelf(event)) {

spring-cloud-bus/src/main/java/org/springframework/cloud/bus/event/EnvironmentChangeRemoteApplicationEvent.java

@@ -18,6 +18,8 @@ package org.springframework.cloud.bus.event;
 
 import java.util.Map;
 
+import org.springframework.core.style.ToStringCreator;
+
 /**
  * @author Spencer Gibb
  */
@@ -73,4 +75,13 @@ public class EnvironmentChangeRemoteApplicationEvent extends RemoteApplicationEv
 		return true;
 	}
 
+	@Override
+	public String toString() {
+		return new ToStringCreator(this).append("id", getId())
+				.append("originService", getOriginService())
+				.append("destinationService", getDestinationService())
+				.append("values", values).toString();
+
+	}
+
 }

spring-cloud-bus/src/main/java/org/springframework/cloud/bus/event/RemoteApplicationEvent.java

@@ -22,6 +22,7 @@ import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
 import com.fasterxml.jackson.annotation.JsonTypeInfo;
 
 import org.springframework.context.ApplicationEvent;
+import org.springframework.core.style.ToStringCreator;
 import org.springframework.util.StringUtils;
 
 /**
@@ -134,4 +135,12 @@ public abstract class RemoteApplicationEvent extends ApplicationEvent {
 		return true;
 	}
 
+	@Override
+	public String toString() {
+		return new ToStringCreator(this).append("id", id)
+				.append("originService", originService)
+				.append("destinationService", destinationService).toString();
+
+	}
+
 }

spring-cloud-bus/src/main/java/org/springframework/cloud/bus/event/UnknownRemoteApplicationEvent.java

@@ -16,6 +16,8 @@
 
 package org.springframework.cloud.bus.event;
 
+import org.springframework.core.style.ToStringCreator;
+
 /**
  * @author Stefan Pfeiffer
  */
@@ -49,7 +51,20 @@ public class UnknownRemoteApplicationEvent extends RemoteApplicationEvent {
 	}
 
 	public String getPayloadAsString() {
-		return new String(this.payload);
+		if (this.payload != null) {
+			return new String(this.payload);
+		}
+		return null;
+	}
+
+	@Override
+	public String toString() {
+		return new ToStringCreator(this).append("id", getId())
+				.append("originService", getOriginService())
+				.append("destinationService", getDestinationService())
+				.append("typeInfo", typeInfo).append("payload", getPayloadAsString())
+				.toString();
+
 	}
 
 }