content: /*
   *
   * Copyright 1999-2021 Alibaba Group Holding Ltd.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   *
   */
  
  package com.alibaba.nacos.core.namespace.filter;
  
  import com.alibaba.nacos.api.exception.NacosException;
  import com.alibaba.nacos.api.remote.request.Request;
  import com.alibaba.nacos.api.remote.request.RequestMeta;
  import com.alibaba.nacos.api.remote.response.Response;
  import com.alibaba.nacos.api.model.v2.ErrorCode;
  import com.alibaba.nacos.common.paramcheck.ParamInfo;
  import com.alibaba.nacos.common.utils.CollectionUtils;
  import com.alibaba.nacos.common.utils.StringUtils;
  import com.alibaba.nacos.core.paramcheck.AbstractRpcParamExtractor;
  import com.alibaba.nacos.core.paramcheck.ExtractorManager;
  import com.alibaba.nacos.core.remote.AbstractRequestFilter;
  import com.alibaba.nacos.core.service.NamespaceOperationService;
  
  import com.alibaba.nacos.core.utils.Loggers;
  import org.springframework.stereotype.Component;
  
  import java.lang.reflect.Method;
  import java.util.List;
  
  /**
   * Namespace validation request filter for NamingRequest.
   *
   * @author FangYuan
   * @since 2025-08-11 21:51:29
   */
  @Component
  public class NamespaceValidationRequestFilter extends AbstractRequestFilter {
  
      private final NamespaceOperationService namespaceOperationService;
  
      public NamespaceValidationRequestFilter(NamespaceOperationService namespaceOperationService) {
          this.namespaceOperationService = namespaceOperationService;
      }
  
      @Override
      protected Response filter(Request request, RequestMeta meta, Class handlerClazz) throws NacosException {
          try {
              // check global namespace validation config
              boolean namespaceValidationEnabled = NamespaceValidationConfig.getInstance().isNamespaceValidationEnabled();
              if (!namespaceValidationEnabled) {
                  return null;
              }
  
              // check namespace validation
              Method method = getHandleMethod(handlerClazz);
              if (method.isAnnotationPresent(NamespaceValidation.class)) {
                  NamespaceValidation namespaceValidation = method.getAnnotation(NamespaceValidation.class);
                  if (!namespaceValidation.enable()) {
                      return null;
                  }
  
                  List<ParamInfo> paramInfoList = extractNamespaceParam(request, handlerClazz);
                  if (CollectionUtils.isEmpty(paramInfoList)) {
                      return null;
                  }
  
                  for (ParamInfo paramInfo : paramInfoList) {
                      // if namespace param is null or '', don't need to check namespace
                      String namespaceId = paramInfo.getNamespaceId();
                      if (StringUtils.isBlank(namespaceId)) {
                          continue;
                      }
  
                      boolean exist = namespaceOperationService.namespaceExists(namespaceId);
                      if (!exist) {
                          Response response = super.getDefaultResponseInstance(handlerClazz);
                          response.setErrorInfo(ErrorCode.NAMESPACE_NOT_EXIST.getCode(),
                                  String.format("Namespace '%s' does not exist. Please create the namespace first.", namespaceId));
  
                          return response;
                      }
                  }
              }
          } catch (Exception e) {
              Loggers.CORE.warn("Namespace validation error for request: {}, exception: {}", request, e);
          }
  
          return null;
      }
  
      @SuppressWarnings("unchecked")
      private List<ParamInfo> extractNamespaceParam(Request request, Class handlerClazz) throws NacosException {
          ExtractorManager.Extractor extractor = getHandleMethod(handlerClazz).getAnnotation(ExtractorManager.Extractor.class);
          if (extractor == null) {
              extractor = (ExtractorManager.Extractor) handlerClazz.getAnnotation(ExtractorManager.Extractor.class);
              if (extractor == null) {
                  return null;
              }
          }
          AbstractRpcParamExtractor paramExtractor = ExtractorManager.getRpcExtractor(extractor);
          return paramExtractor.extractParam(request);
      }
  }