Merge branch 'flush-user-cache' of https://github.com/dlin2028/security into flush-user-cache

Signed-off-by: David Lin <dlin2028@gmail.com>

Author: dlin2028

src/main/java/org/opensearch/security/dlic/rest/api/FlushCacheApiAction.java

@@ -62,6 +62,21 @@ public List<Route> routes() {
     }
 
     private void flushCacheApiRequestHandlers(RequestHandler.RequestHandlersBuilder requestHandlersBuilder) {
+        requestHandlersBuilder.allMethodsNotImplemented().override(Method.DELETE, (channel, request, client) -> {
+            final ConfigUpdateRequest configUpdateRequest;
+            if (request.path().contains("/user/")) {
+                // Extract the username from the request
+                final String username = request.param("username");
+                if (username == null || username.isEmpty()) {
+                    internalSeverError(channel, "No username provided for cache invalidation.");
+                    return;
+                }
+                // Validate and handle user-specific cache invalidation
+                configUpdateRequest = new ConfigUpdateRequest(CType.INTERNALUSERS.toLCString(), new String[] { username });
+            } else {
+                configUpdateRequest = new ConfigUpdateRequest(CType.lcStringValues().toArray(new String[0]));
+            }
+            client.execute(ConfigUpdateAction.INSTANCE, configUpdateRequest, new ActionListener<>() {
         requestHandlersBuilder.allMethodsNotImplemented().override(Method.DELETE, (channel, request, client) -> {
             final ConfigUpdateRequest configUpdateRequest;
             if (request.path().contains("/user/")) {
@@ -105,16 +120,11 @@ public void onResponse(ConfigUpdateResponse configUpdateResponse) {
                             ok(channel, "Cache flushed successfully.");
                         }
 
-                                @Override
-                                public void onFailure(final Exception e) {
-                                    LOGGER.error("Cannot flush cache due to", e);
-                                    internalSeverError(channel, "Cannot flush cache due to " + e.getMessage() + ".");
-                                }
-                        @Override
-                        public void onFailure(final Exception e) {
-                            LOGGER.error("Cannot flush cache due to", e);
-                            internalServerError(channel, "Cannot flush cache due to " + e.getMessage() + ".");
-                        }
+                @Override
+                public void onFailure(final Exception e) {
+                    LOGGER.error("Cannot flush cache due to", e);
+                    internalSeverError(channel, "Cannot flush cache due to " + e.getMessage() + ".");
+                }
 
             });
         });