[auth] UserRegistryImpl: Allow registering additional ManagedProviders & Allow field access for subclasses of GenericUser (#5328)

Signed-off-by: Florian Hotze <dev@florianhotze.com>

bundles/org.openhab.core/src/main/java/org/openhab/core/auth/GenericUser.java

@@ -21,13 +21,11 @@ import org.eclipse.jdt.annotation.NonNullByDefault;
  * Represents a generic {@link User} with a set of roles
  *
  * @author Yannick Schaus - initial contribution
- *
  */
 @NonNullByDefault
 public class GenericUser implements User {
-
-    private String name;
-    private Set<String> roles;
+    protected String name;
+    protected Set<String> roles;
 
     /**
      * Constructs a user attributed with a set of roles.
@@ -63,4 +61,9 @@ public class GenericUser implements User {
     public Set<String> getRoles() {
         return roles;
     }
+
+    @Override
+    public String toString() {
+        return "User (name=" + name + ", roles=" + String.join(", ", roles) + ")";
+    }
 }

bundles/org.openhab.core/src/main/java/org/openhab/core/internal/auth/UserRegistryImpl.java

@@ -26,6 +26,7 @@ import javax.crypto.SecretKeyFactory;
 import javax.crypto.spec.PBEKeySpec;
 
 import org.eclipse.jdt.annotation.NonNullByDefault;
+import org.eclipse.jdt.annotation.Nullable;
 import org.openhab.core.auth.AuthenticatedUser;
 import org.openhab.core.auth.Authentication;
 import org.openhab.core.auth.AuthenticationException;
@@ -39,6 +40,8 @@ import org.openhab.core.auth.UserRegistry;
 import org.openhab.core.auth.UserSession;
 import org.openhab.core.auth.UsernamePasswordCredentials;
 import org.openhab.core.common.registry.AbstractRegistry;
+import org.openhab.core.common.registry.ManagedProvider;
+import org.openhab.core.common.registry.Provider;
 import org.osgi.framework.BundleContext;
 import org.osgi.service.component.annotations.Activate;
 import org.osgi.service.component.annotations.Component;
@@ -256,6 +259,19 @@ public class UserRegistryImpl extends AbstractRegistry<User, String, UserProvide
         update(user);
     }
 
+    @Override
+    public @Nullable User update(User element) {
+        String key = element.getName();
+        Provider<User> provider = getProvider(key);
+        // If the provider of this element is a ManagedProvider,
+        // invoke the update method of that provider instead of the default one
+        // This allows for registering additional ManagedProviders, e.g., for providing LDAP users
+        if (provider instanceof ManagedProvider<User, ?> managedProvider) {
+            return managedProvider.update(element);
+        }
+        return super.update(element);
+    }
+
     @Override
     public boolean supports(Class<? extends Credentials> type) {
         return (UsernamePasswordCredentials.class.isAssignableFrom(type));