Adding utility class for working with throwables and updating the cause check to limit the number of iterations on the stacktrace

Signed-off-by: Pedro Igor <pigor.craveiro@gmail.com>

common/src/main/java/org/keycloak/common/util/Throwables.java

@@ -0,0 +1,38 @@
+package org.keycloak.common.util;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.Objects;
+
+/**
+ * A utility class for working with {@link Throwable} instances.
+ */
+public final class Throwables {
+
+    /**
+     * Checks if the given {@code throwable} or any of its causes (up to a depth of 3) is an instance of any of the specified exception types.
+     *
+     * @param throwable
+     * @param type
+     * @return
+     */
+    @SafeVarargs
+    public static boolean isCausedBy(Throwable throwable, Class<? extends Exception>... type) {
+        Objects.requireNonNull(throwable, "Throwable must not be null");
+        int limit = 3;
+        List<Class<? extends Exception>> types = Arrays.asList(type);
+        Throwable cause = throwable.getCause();
+
+        while (cause != null) {
+            if (limit-- == 0) {
+                break;
+            }
+            if (types.contains(cause.getClass())) {
+                return true;
+            }
+            cause = cause.getCause();
+        }
+
+        return false;
+    }
+}

federation/ldap/src/main/java/org/keycloak/storage/ldap/idm/query/internal/LDAPQuery.java

@@ -49,6 +49,7 @@ import java.util.List;
 import java.util.Set;
 
 import static java.util.Collections.unmodifiableSet;
+import static org.keycloak.common.util.Throwables.isCausedBy;
 
 /**
  * Default IdentityQuery implementation.
@@ -186,17 +187,9 @@ public class LDAPQuery implements AutoCloseable {
                 result.add(ldapObject);
             }
         } catch (Exception e) {
-            // Check if this is an LDAP connectivity issue
+            if (isCausedBy(e, NameNotFoundException.class, CommunicationException.class, AuthenticationException.class)) {
-            Throwable current = e;
+                throw new StorageUnavailableException("LDAP server is unavailable for provider [" + ldapFedProvider.getModel().getName() + "]", e);
-            while (current != null) {
-                if (current instanceof NameNotFoundException || current instanceof CommunicationException || 
-                    current instanceof AuthenticationException) {
-                    throw new StorageUnavailableException("LDAP server is unavailable for provider [" + 
-                                                          ldapFedProvider.getModel().getName() + "]", e);
-                }
-                current = current.getCause();
             }
-            
             throw new ModelException("Failed to fetch results from the LDAP [" + ldapFedProvider.getModel().getName() + "] provider", e);
         }
 

server-spi/src/main/java/org/keycloak/models/ModelException.java

@@ -17,7 +17,7 @@
 
 package org.keycloak.models;
 
-import java.util.List;
+import org.keycloak.common.util.Throwables;
 
 /**
  * @author <a href="mailto:sthorger@redhat.com">Stian Thorgersen</a>
@@ -52,20 +52,6 @@ public class ModelException extends RuntimeException {
 
     @SafeVarargs
     public final boolean isCausedBy(Class<? extends Exception>... type) {
-        int limit = 3;
+        return Throwables.isCausedBy(this, type);
-        List<Class<? extends Exception>> types = List.of(type);
-        Throwable cause = getCause();
-
-        while (cause != null) {
-            if (limit-- == 0) {
-                break;
-            }
-            if (types.contains(cause.getClass())) {
-                return true;
-            }
-            cause = cause.getCause();
-        }
-
-        return false;
     }
 }