Use Apache Commons Logging instead of SLF4J.

Align logging API use with Spring Boot and Spring Cloud. Drop slf4j dependency from pom files.

Closes gh-84.

spring-cloud-vault-config/pom.xml

@@ -1,5 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<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">
+<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>
 
 	<parent>
@@ -19,7 +21,13 @@
 			<artifactId>spring-vault-core</artifactId>
 		</dependency>
 
- 		<dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-logging</artifactId>
+			<optional>true</optional>
+		</dependency>
+
+		<dependency>
 			<groupId>org.springframework.boot</groupId>
 			<artifactId>spring-boot-starter-actuator</artifactId>
 			<optional>true</optional>
@@ -35,11 +43,6 @@
 			<artifactId>spring-web</artifactId>
 		</dependency>
 
-		<dependency>
-			<groupId>org.slf4j</groupId>
-			<artifactId>slf4j-api</artifactId>
-		</dependency>
-
 		<dependency>
 			<groupId>org.apache.httpcomponents</groupId>
 			<artifactId>httpclient</artifactId>

spring-cloud-vault-config/src/main/java/org/springframework/cloud/vault/config/LeasingVaultPropertySource.java

@@ -25,9 +25,7 @@ import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicReference;
 
-import lombok.extern.slf4j.Slf4j;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
+import lombok.extern.apachecommons.CommonsLog;
 
 import org.springframework.beans.factory.DisposableBean;
 import org.springframework.http.HttpMethod;
@@ -54,7 +52,7 @@ import org.springframework.web.client.RestOperations;
  *
  * @author Mark Paluch
  */
-@Slf4j
+@CommonsLog
 class LeasingVaultPropertySource extends VaultPropertySource implements DisposableBean {
 
 	private final LeaseRenewalScheduler leaseRenewal;
@@ -197,8 +195,8 @@ class LeasingVaultPropertySource extends VaultPropertySource implements Disposab
 				return null;
 			}
 
-			return Lease.of(leaseId, leaseDuration != null ? leaseDuration.longValue()
-					: 0, renewable);
+			return Lease.of(leaseId,
+					leaseDuration != null ? leaseDuration.longValue() : 0, renewable);
 		}
 		catch (HttpStatusCodeException e) {
 			throw new VaultException(String.format("Cannot renew lease: %s",
@@ -242,10 +240,9 @@ class LeasingVaultPropertySource extends VaultPropertySource implements Disposab
 	 * a newer {@link Lease} for renewal, the previously registered renewal task will skip
 	 * renewal.
 	 */
+	@CommonsLog
 	private static class LeaseRenewalScheduler {
 
-		private final Logger logger = LoggerFactory.getLogger(getClass());
-
 		private final TaskScheduler taskScheduler;
 
 		private final AtomicReference<Lease> currentLease = new AtomicReference<>();
@@ -273,8 +270,11 @@ class LeasingVaultPropertySource extends VaultPropertySource implements Disposab
 		void scheduleRenewal(final RenewLease renewLease, final Lease lease,
 				final int minRenewalSeconds, final int expiryThresholdSeconds) {
 
-			logger.debug("Scheduling renewal for lease {}, lease duration {}",
-					lease.getLeaseId(), lease.getLeaseDuration());
+			if (log.isDebugEnabled()) {
+				log.debug(String.format(
+						"Scheduling renewal for lease %s, lease duration %d",
+						lease.getLeaseId(), lease.getLeaseDuration()));
+			}
 
 			Lease currentLease = this.currentLease.get();
 			this.currentLease.set(lease);
@@ -283,32 +283,35 @@ class LeasingVaultPropertySource extends VaultPropertySource implements Disposab
 				cancelSchedule(currentLease);
 			}
 
-			ScheduledFuture<?> scheduledFuture = taskScheduler.schedule(
-					new Runnable() {
+			ScheduledFuture<?> scheduledFuture = taskScheduler.schedule(new Runnable() {
 
-						@Override
-						public void run() {
+				@Override
+				public void run() {
 
-							try {
-								schedules.remove(lease);
+					try {
 
-								if (LeaseRenewalScheduler.this.currentLease.get() != lease) {
-									logger.debug("Current lease has changed. Skipping renewal");
-									return;
-								}
+						schedules.remove(lease);
 
-								logger.debug("Renewing lease {}", lease.getLeaseId());
-								LeaseRenewalScheduler.this.currentLease.compareAndSet(
-										lease, renewLease.renewLease(lease));
-							}
-							catch (Exception e) {
-								logger.error("Cannot renew lease {}", lease.getLeaseId(),
-										e);
-							}
+						if (LeaseRenewalScheduler.this.currentLease.get() != lease) {
+							log.debug("Current lease has changed. Skipping renewal");
+							return;
 						}
-					},
-					new OneShotTrigger(getRenewalSeconds(lease, minRenewalSeconds,
-							expiryThresholdSeconds)));
+
+						if (log.isDebugEnabled()) {
+							log.debug(String.format("Renewing lease %s",
+									lease.getLeaseId()));
+						}
+
+						LeaseRenewalScheduler.this.currentLease.compareAndSet(lease,
+								renewLease.renewLease(lease));
+					}
+					catch (Exception e) {
+						log.error(String.format("Cannot renew lease %s",
+								lease.getLeaseId()), e);
+					}
+				}
+			}, new OneShotTrigger(
+					getRenewalSeconds(lease, minRenewalSeconds, expiryThresholdSeconds)));
 
 			schedules.put(lease, scheduledFuture);
 		}
@@ -317,8 +320,13 @@ class LeasingVaultPropertySource extends VaultPropertySource implements Disposab
 
 			ScheduledFuture<?> scheduledFuture = schedules.get(lease);
 			if (scheduledFuture != null) {
-				logger.debug("Canceling previously registered schedule for lease {}",
-						lease.getLeaseId());
+
+				if (log.isDebugEnabled()) {
+					log.debug(String.format(
+							"Canceling previously registered schedule for lease %s",
+							lease.getLeaseId()));
+				}
+
 				scheduledFuture.cancel(false);
 			}
 		}
@@ -339,8 +347,8 @@ class LeasingVaultPropertySource extends VaultPropertySource implements Disposab
 
 		private long getRenewalSeconds(Lease lease, int minRenewalSeconds,
 				int expiryThresholdSeconds) {
-			return Math.max(minRenewalSeconds, lease.getLeaseDuration()
-					- expiryThresholdSeconds);
+			return Math.max(minRenewalSeconds,
+					lease.getLeaseDuration() - expiryThresholdSeconds);
 		}
 
 		private boolean isLeaseRenewable(Lease lease) {
@@ -367,8 +375,8 @@ class LeasingVaultPropertySource extends VaultPropertySource implements Disposab
 		public Date nextExecutionTime(TriggerContext triggerContext) {
 
 			if (fired.compareAndSet(false, true)) {
-				return new Date(System.currentTimeMillis()
-						+ TimeUnit.SECONDS.toMillis(seconds));
+				return new Date(
+						System.currentTimeMillis() + TimeUnit.SECONDS.toMillis(seconds));
 			}
 
 			return null;

spring-cloud-vault-config/src/main/java/org/springframework/cloud/vault/config/LeasingVaultPropertySourceLocator.java

@@ -19,13 +19,13 @@ import java.util.Collection;
 import java.util.HashSet;
 import java.util.Set;
 
+import lombok.extern.apachecommons.CommonsLog;
+
 import org.springframework.beans.factory.DisposableBean;
 import org.springframework.core.env.PropertySource;
 import org.springframework.scheduling.TaskScheduler;
 import org.springframework.util.Assert;
 
-import lombok.extern.slf4j.Slf4j;
-
 /**
  * Extension to {@link LeasingVaultPropertySourceLocator} that creates
  * {@link LeasingVaultPropertySource}s.
@@ -33,7 +33,7 @@ import lombok.extern.slf4j.Slf4j;
  * @author Mark Paluch
  * @see LeasingVaultPropertySource
  */
-@Slf4j
+@CommonsLog
 class LeasingVaultPropertySourceLocator extends VaultPropertySourceLocator
 		implements DisposableBean {
 
@@ -97,8 +97,8 @@ class LeasingVaultPropertySourceLocator extends VaultPropertySourceLocator
 					((LeasingVaultPropertySource) propertySource).destroy();
 				}
 				catch (Exception e) {
-					log.warn("Cannot destroy property source {}",
-							propertySource.getName(), e);
+					log.warn(String.format("Cannot destroy property source %s",
+							propertySource.getName()), e);
 				}
 			}
 		}

spring-cloud-vault-config/src/main/java/org/springframework/cloud/vault/config/SecretBackendFactories.java

@@ -20,7 +20,7 @@ import java.util.Collection;
 import java.util.List;
 
 import lombok.experimental.UtilityClass;
-import lombok.extern.slf4j.Slf4j;
+import lombok.extern.apachecommons.CommonsLog;
 
 /**
  * Utility class to create {@link SecretBackendMetadata} from a
@@ -28,7 +28,7 @@ import lombok.extern.slf4j.Slf4j;
  *
  * @author Mark Paluch
  */
-@Slf4j
+@CommonsLog
 @UtilityClass
 class SecretBackendFactories {
 

spring-cloud-vault-config/src/main/java/org/springframework/cloud/vault/config/VaultConfigTemplate.java

@@ -18,7 +18,7 @@ package org.springframework.cloud.vault.config;
 import java.net.URI;
 import java.util.Map;
 
-import lombok.extern.slf4j.Slf4j;
+import lombok.extern.apachecommons.CommonsLog;
 
 import org.springframework.util.Assert;
 import org.springframework.vault.VaultException;
@@ -34,7 +34,7 @@ import org.springframework.web.util.DefaultUriTemplateHandler;
  * @author Mark Paluch
  * @see VaultOperations
  */
-@Slf4j
+@CommonsLog
 public class VaultConfigTemplate implements VaultConfigOperations {
 
 	private final DefaultUriTemplateHandler templateHandler = new DefaultUriTemplateHandler();
@@ -47,7 +47,8 @@ public class VaultConfigTemplate implements VaultConfigOperations {
 	 * @param vaultOperations must not be {@literal null}.
 	 * @param properties must not be {@literal null}.
 	 */
-	public VaultConfigTemplate(VaultOperations vaultOperations, VaultProperties properties) {
+	public VaultConfigTemplate(VaultOperations vaultOperations,
+			VaultProperties properties) {
 
 		Assert.notNull(vaultOperations, "VaultOperations must not be null!");
 		Assert.notNull(properties, "VaultProperties must not be null!");

spring-cloud-vault-config/src/main/java/org/springframework/cloud/vault/config/VaultPropertySource.java

@@ -19,18 +19,18 @@ import java.util.LinkedHashMap;
 import java.util.Map;
 import java.util.Set;
 
+import lombok.extern.apachecommons.CommonsLog;
+
 import org.springframework.core.env.EnumerablePropertySource;
 import org.springframework.util.Assert;
 
-import lombok.extern.slf4j.Slf4j;
-
 /**
  * A {@link EnumerablePropertySource} backed by {@link VaultConfigTemplate}.
  *
  * @author Spencer Gibb
  * @author Mark Paluch
  */
-@Slf4j
+@CommonsLog
 class VaultPropertySource extends EnumerablePropertySource<VaultConfigOperations> {
 
 	private final boolean failFast;

spring-cloud-vault-dependencies/pom.xml

@@ -25,7 +25,6 @@
 		<netty.version>4.1.6.Final</netty.version>
 		<okhttp.version>2.7.5</okhttp.version>
 		<okhttp3.version>3.5.0</okhttp3.version>
-		<slf4j.version>1.7.21</slf4j.version>
 	</properties>
 
 	<dependencyManagement>
@@ -140,12 +139,6 @@
 				<optional>true</optional>
 			</dependency>
 
-			<!-- Logging -->
-			<dependency>
-				<groupId>org.slf4j</groupId>
-				<artifactId>slf4j-api</artifactId>
-				<version>${slf4j.version}</version>
-			</dependency>
 		</dependencies>
 	</dependencyManagement>