Log exception when KeyValueDelegate.getMountInfo(…) fails.

Closes gh-888

Author: mp911de

spring-vault-core/src/main/java/org/springframework/vault/core/util/KeyValueDelegate.java

@@ -20,6 +20,9 @@
 import java.util.Map;
 import java.util.function.Supplier;
 
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+
 import org.springframework.lang.Nullable;
 import org.springframework.util.ConcurrentReferenceHashMap;
 import org.springframework.util.StringUtils;
@@ -40,6 +43,8 @@
  */
 public class KeyValueDelegate {
 
+	private static final Log logger = LogFactory.getLog(KeyValueDelegate.class);
+
 	private final Map<String, MountInfo> mountInfo;
 
 	private final VaultOperations operations;
@@ -125,13 +130,20 @@ public MountInfo getMountInfo(String path) {
 
 		if (mountInfo == null) {
 			try {
-
 				mountInfo = doGetMountInfo(path);
 			}
 			catch (VaultException e) {
+				if (logger.isDebugEnabled()) {
+					logger.debug("Unable to determine mount information for [%s]. Returning unavailable MountInfo: %s"
+						.formatted(path, e.getMessage()), e);
+				}
 				return MountInfo.unavailable();
 			}
 			catch (RuntimeException e) {
+				if (logger.isDebugEnabled()) {
+					logger.debug("Unable to determine mount information for [%s]. Caching unavailable MountInfo: %s"
+						.formatted(path, e.getMessage()), e);
+				}
 				mountInfo = MountInfo.unavailable();
 			}