[ISSUE #13023]Add Unit Test for ConfigQueryHandlerChainn and optimize…

… the logic (#13024)

 optimize Config Query Chain logic

config/src/main/java/com/alibaba/nacos/config/server/controller/ConfigServletInner.java

@@ -30,9 +30,9 @@
 import com.alibaba.nacos.config.server.model.ConfigCacheGray;
 import com.alibaba.nacos.config.server.model.gray.BetaGrayRule;
 import com.alibaba.nacos.config.server.model.gray.TagGrayRule;
+import com.alibaba.nacos.config.server.service.LongPollingService;
 import com.alibaba.nacos.config.server.service.query.ConfigChainRequestExtractorService;
 import com.alibaba.nacos.config.server.service.query.ConfigQueryChainService;
-import com.alibaba.nacos.config.server.service.LongPollingService;
 import com.alibaba.nacos.config.server.service.query.enums.ResponseCode;
 import com.alibaba.nacos.config.server.service.query.model.ConfigQueryChainRequest;
 import com.alibaba.nacos.config.server.service.query.model.ConfigQueryChainResponse;
@@ -81,6 +81,12 @@ public ConfigServletInner(LongPollingService longPollingService, ConfigQueryChai
         this.configQueryChainService = configQueryChainService;
     }
 
+    private static String getDecryptContent(ConfigQueryChainResponse chainResponse, String dataId) {
+        Pair<String, String> pair = EncryptionHandler.decryptHandler(dataId, chainResponse.getEncryptedDataKey(),
+                chainResponse.getContent());
+        return pair.getSecond();
+    }
+
     /**
      * long polling the config.
      */
@@ -142,6 +148,7 @@ public String doGetConfig(HttpServletRequest request, HttpServletResponse respon
 
         switch (chainResponse.getStatus()) {
             case CONFIG_NOT_FOUND:
+            case SPECIAL_TAG_CONFIG_NOT_FOUND:
                 return handlerConfigNotFound(response, apiVersion);
             case CONFIG_QUERY_CONFLICT:
                 return handlerConfigConflict(response, apiVersion);
@@ -162,9 +169,11 @@ private String handlerConfigNotFound(HttpServletResponse response, ApiVersionEnu
     private String handlerConfigConflict(HttpServletResponse response, ApiVersionEnum apiVersion) throws IOException {
         response.setStatus(HttpServletResponse.SC_CONFLICT);
         if (apiVersion == ApiVersionEnum.V1) {
-            return writeResponseForV1(response, Result.failure(ErrorCode.RESOURCE_CONFLICT, "requested file is being modified, please try later."));
+            return writeResponseForV1(response,
+                    Result.failure(ErrorCode.RESOURCE_CONFLICT, "requested file is being modified, please try later."));
         } else {
-            return writeResponseForV2(response, Result.failure(ErrorCode.RESOURCE_CONFLICT, "requested file is being modified, please try later."));
+            return writeResponseForV2(response,
+                    Result.failure(ErrorCode.RESOURCE_CONFLICT, "requested file is being modified, please try later."));
         }
     }
 
@@ -204,10 +213,11 @@ private String handleResponseForV2(HttpServletResponse response, ConfigQueryChai
     }
 
     private void setResponseHeadForV1(HttpServletResponse response, ConfigQueryChainResponse chainResponse) {
-        String contentType = chainResponse.getContentType() != null ? chainResponse.getContentType() : FileTypeEnum.TEXT.getFileType();
-        FileTypeEnum fileTypeEnum = FileTypeEnum.getFileTypeEnumByFileExtensionOrFileType(contentType);
-        String contentTypeHeader = fileTypeEnum.getContentType();
-        response.setHeader(HttpHeaderConsts.CONTENT_TYPE, contentTypeHeader);
+        String contentType = chainResponse.getContentType();
+        if (StringUtils.isBlank(contentType)) {
+            contentType = FileTypeEnum.TEXT.getContentType();
+        }
+        response.setHeader(HttpHeaderConsts.CONTENT_TYPE, contentType);
     }
 
     private void setResponseHeadForV2(HttpServletResponse response) {
@@ -238,12 +248,6 @@ private void writeContentForV2(HttpServletResponse response, ConfigQueryChainRes
         }
     }
 
-    private static String getDecryptContent(ConfigQueryChainResponse chainResponse, String dataId) {
-        Pair<String, String> pair = EncryptionHandler.decryptHandler(dataId, chainResponse.getEncryptedDataKey(),
-                chainResponse.getContent());
-        return pair.getSecond();
-    }
-
     private String writeResponseForV1(HttpServletResponse response, Result<String> result) throws IOException {
         PrintWriter writer = response.getWriter();
         writer.println(result.getData());
@@ -282,20 +286,23 @@ private void logPullEvent(String dataId, String group, String tenant, String req
         if (status == ConfigQueryChainResponse.ConfigQueryStatus.CONFIG_QUERY_CONFLICT) {
             ConfigTraceService.logPullEvent(dataId, group, tenant, requestIpApp, -1, pullEvent,
                     ConfigTraceService.PULL_TYPE_CONFLICT, -1, clientIp, notify, "http");
-        } else if (status == ConfigQueryChainResponse.ConfigQueryStatus.CONFIG_NOT_FOUND || chainResponse.getContent() == null) {
+        } else if (status == ConfigQueryChainResponse.ConfigQueryStatus.CONFIG_NOT_FOUND
+                || chainResponse.getContent() == null) {
             ConfigTraceService.logPullEvent(dataId, group, tenant, requestIpApp, -1, pullEvent,
                     ConfigTraceService.PULL_TYPE_NOTFOUND, -1, clientIp, notify, "http");
         } else {
             long delayed = notify ? -1 : System.currentTimeMillis() - chainResponse.getLastModified();
-            ConfigTraceService.logPullEvent(dataId, group, tenant, requestIpApp, chainResponse.getLastModified(), pullEvent,
-                    ConfigTraceService.PULL_TYPE_OK, delayed, clientIp, notify, "http");
+            ConfigTraceService.logPullEvent(dataId, group, tenant, requestIpApp, chainResponse.getLastModified(),
+                    pullEvent, ConfigTraceService.PULL_TYPE_OK, delayed, clientIp, notify, "http");
         }
     }
 
-    private void setCommonResponseHead(HttpServletResponse response, ConfigQueryChainResponse chainResponse, String tag) {
-        String contentType = chainResponse.getContentType() != null ? chainResponse.getContentType() : FileTypeEnum.TEXT.getFileType();
+    private void setCommonResponseHead(HttpServletResponse response, ConfigQueryChainResponse chainResponse,
+            String tag) {
+        String configType = chainResponse.getConfigType() != null ? chainResponse.getConfigType()
+                : FileTypeEnum.TEXT.getFileType();
 
-        response.setHeader(CONFIG_TYPE, contentType);
+        response.setHeader(CONFIG_TYPE, configType);
         response.setHeader(CONTENT_MD5, chainResponse.getMd5());
         response.setHeader("Pragma", "no-cache");
         response.setDateHeader("Expires", 0);
@@ -312,8 +319,9 @@ private void setCommonResponseHead(HttpServletResponse response, ConfigQueryChai
                 response.setHeader("isBeta", "true");
             } else if (TagGrayRule.TYPE_TAG.equals(chainResponse.getMatchedGray().getGrayRule().getType())) {
                 try {
-                    response.setHeader(TagGrayRule.TYPE_TAG, URLEncoder.encode(chainResponse.getMatchedGray().getGrayRule().getRawGrayRuleExp(),
-                            StandardCharsets.UTF_8.displayName()));
+                    response.setHeader(TagGrayRule.TYPE_TAG,
+                            URLEncoder.encode(chainResponse.getMatchedGray().getGrayRule().getRawGrayRuleExp(),
+                                    StandardCharsets.UTF_8.displayName()));
                 } catch (Exception e) {
                     LOGGER.error("Error encoding tag", e);
                 }

config/src/main/java/com/alibaba/nacos/config/server/remote/ConfigQueryRequestHandler.java

@@ -114,6 +114,7 @@ public ConfigQueryResponse handle(ConfigQueryRequest request, RequestMeta meta)
             response.setMd5(chainResponse.getMd5());
             response.setEncryptedDataKey(chainResponse.getEncryptedDataKey());
             response.setContent(chainResponse.getContent());
+            response.setContentType(chainResponse.getConfigType());
             response.setLastModified(chainResponse.getLastModified());
 
             String pullType = ConfigTraceService.PULL_TYPE_OK;

config/src/main/java/com/alibaba/nacos/config/server/service/query/DefaultConfigQueryHandlerChainBuilder.java

@@ -17,6 +17,7 @@
 package com.alibaba.nacos.config.server.service.query;
 
 import com.alibaba.nacos.config.server.service.query.handler.ConfigChainEntryHandler;
+import com.alibaba.nacos.config.server.service.query.handler.ConfigContentTypeHandler;
 import com.alibaba.nacos.config.server.service.query.handler.FormalHandler;
 import com.alibaba.nacos.config.server.service.query.handler.GrayRuleMatchHandler;
 import com.alibaba.nacos.config.server.service.query.handler.SpecialTagNotFoundHandler;
@@ -32,6 +33,7 @@ public class DefaultConfigQueryHandlerChainBuilder implements ConfigQueryHandler
     public ConfigQueryHandlerChain build() {
         ConfigQueryHandlerChain chain = new ConfigQueryHandlerChain();
         chain.addHandler(new ConfigChainEntryHandler())
+                .addHandler(new ConfigContentTypeHandler())
                 .addHandler(new GrayRuleMatchHandler())
                 .addHandler(new SpecialTagNotFoundHandler())
                 .addHandler(new FormalHandler());

config/src/main/java/com/alibaba/nacos/config/server/service/query/handler/AbstractConfigQueryHandler.java

@@ -17,22 +17,23 @@
 package com.alibaba.nacos.config.server.service.query.handler;
 
 /**
- * AbstractConfigQueryHandler.
- * This abstract class provides a base implementation for configuration query handlers.
- * It implements the {@link ConfigQueryHandler} interface and handles the chaining of handlers.
+ * AbstractConfigQueryHandler. This abstract class provides a base implementation for configuration query handlers. It
+ * implements the {@link ConfigQueryHandler} interface and handles the chaining of handlers.
  *
  * @author Nacos
  */
 public abstract class AbstractConfigQueryHandler implements ConfigQueryHandler {
 
     public ConfigQueryHandler nextHandler;
 
-    public void setNextHandler(ConfigQueryHandler nextHandler) {
-        this.nextHandler = nextHandler;
-    }
-
+    @Override
     public ConfigQueryHandler getNextHandler() {
         return this.nextHandler;
     }
 
+    @Override
+    public void setNextHandler(ConfigQueryHandler nextHandler) {
+        this.nextHandler = nextHandler;
+    }
+
 }

config/src/main/java/com/alibaba/nacos/config/server/service/query/handler/ConfigContentTypeHandler.java

@@ -0,0 +1,52 @@
+/*
+ * Copyright 1999-2024 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.config.server.service.query.handler;
+
+import com.alibaba.nacos.config.server.enums.FileTypeEnum;
+import com.alibaba.nacos.config.server.service.query.model.ConfigQueryChainRequest;
+import com.alibaba.nacos.config.server.service.query.model.ConfigQueryChainResponse;
+
+import java.io.IOException;
+
+/**
+ * The type Config content type handler.
+ * @author Sunrisea
+ */
+public class ConfigContentTypeHandler extends AbstractConfigQueryHandler {
+
+    private static final String CONFIG_CONTENT_TYPE_HANDLER_NAME = "ConfigContentTypeHandler";
+
+    @Override
+    public String getName() {
+        return CONFIG_CONTENT_TYPE_HANDLER_NAME;
+    }
+
+    @Override
+    public ConfigQueryChainResponse handle(ConfigQueryChainRequest request) throws IOException {
+        ConfigQueryChainResponse response = getNextHandler().handle(request);
+        if (response.getStatus() == ConfigQueryChainResponse.ConfigQueryStatus.CONFIG_NOT_FOUND
+                || response.getStatus() == ConfigQueryChainResponse.ConfigQueryStatus.SPECIAL_TAG_CONFIG_NOT_FOUND) {
+            return response;
+        }
+        String contentType =
+                response.getContentType() != null ? response.getContentType() : FileTypeEnum.TEXT.getFileType();
+        FileTypeEnum fileTypeEnum = FileTypeEnum.getFileTypeEnumByFileExtensionOrFileType(contentType);
+        String contentTypeHeader = fileTypeEnum.getContentType();
+        response.setContentType(contentTypeHeader);
+        return response;
+    }
+}

config/src/main/java/com/alibaba/nacos/config/server/service/query/handler/FormalHandler.java

@@ -16,6 +16,7 @@
 
 package com.alibaba.nacos.config.server.service.query.handler;
 
+import com.alibaba.nacos.common.utils.StringUtils;
 import com.alibaba.nacos.config.server.model.CacheItem;
 import com.alibaba.nacos.config.server.service.dump.disk.ConfigDiskServiceFactory;
 import com.alibaba.nacos.config.server.service.query.model.ConfigQueryChainRequest;
@@ -24,9 +25,9 @@
 import java.io.IOException;
 
 /**
- * Formal Handler.
- * This class represents a formal handler in the configuration query processing chain.
- * If the request has not been processed by previous handlers, it will be handled by this handler.
+ * Formal Handler. This class represents a formal handler in the configuration query processing chain. If the request
+ * has not been processed by previous handlers, it will be handled by this handler.
+ *
  * @author Nacos
  */
 public class FormalHandler extends AbstractConfigQueryHandler {
@@ -48,16 +49,19 @@ public ConfigQueryChainResponse handle(ConfigQueryChainRequest request) throws I
 
         CacheItem cacheItem = ConfigChainEntryHandler.getThreadLocalCacheItem();
         String md5 = cacheItem.getConfigCache().getMd5();
+        String content = ConfigDiskServiceFactory.getInstance().getContent(dataId, group, tenant);
+        if (StringUtils.isBlank(content)) {
+            response.setStatus(ConfigQueryChainResponse.ConfigQueryStatus.CONFIG_NOT_FOUND);
+            return response;
+        }
         long lastModified = cacheItem.getConfigCache().getLastModifiedTs();
         String encryptedDataKey = cacheItem.getConfigCache().getEncryptedDataKey();
-        String contentType = cacheItem.getType();
-        String content = ConfigDiskServiceFactory.getInstance().getContent(dataId, group, tenant);
-
+        String configType = cacheItem.getType();
         response.setContent(content);
         response.setMd5(md5);
         response.setLastModified(lastModified);
         response.setEncryptedDataKey(encryptedDataKey);
-        response.setContentType(contentType);
+        response.setConfigType(configType);
         response.setStatus(ConfigQueryChainResponse.ConfigQueryStatus.CONFIG_FOUND_FORMAL);
 
         return response;

config/src/main/java/com/alibaba/nacos/config/server/service/query/handler/GrayRuleMatchHandler.java

@@ -25,9 +25,8 @@
 import java.io.IOException;
 
 /**
- * GrayRuleMatchHandler.
- * This class represents a gray rule handler in the configuration query processing chain.
- * It checks if the request matches any gray rules and processes the request accordingly.
+ * GrayRuleMatchHandler. This class represents a gray rule handler in the configuration query processing chain. It
+ * checks if the request matches any gray rules and processes the request accordingly.
  *
  * @author Nacos
  */
@@ -69,7 +68,7 @@ public ConfigQueryChainResponse handle(ConfigQueryChainRequest request) throws I
             response.setLastModified(lastModified);
             response.setEncryptedDataKey(encryptedDataKey);
             response.setMatchedGray(matchedGray);
-            response.setContentType(cacheItem.getType());
+            response.setConfigType(cacheItem.getType());
             response.setStatus(ConfigQueryChainResponse.ConfigQueryStatus.CONFIG_FOUND_GRAY);
 
             return response;

config/src/main/java/com/alibaba/nacos/config/server/service/query/handler/SpecialTagNotFoundHandler.java

@@ -17,8 +17,6 @@
 package com.alibaba.nacos.config.server.service.query.handler;
 
 import com.alibaba.nacos.common.utils.StringUtils;
-import com.alibaba.nacos.config.server.model.CacheItem;
-import com.alibaba.nacos.config.server.service.dump.disk.ConfigDiskServiceFactory;
 import com.alibaba.nacos.config.server.service.query.model.ConfigQueryChainRequest;
 import com.alibaba.nacos.config.server.service.query.model.ConfigQueryChainResponse;
 
@@ -43,25 +41,7 @@ public String getName() {
     public ConfigQueryChainResponse handle(ConfigQueryChainRequest request) throws IOException {
         if (StringUtils.isNotBlank(request.getTag())) {
             ConfigQueryChainResponse response = new ConfigQueryChainResponse();
-
-            String dataId = request.getDataId();
-            String group = request.getGroup();
-            String tenant = request.getTenant();
-
-            CacheItem cacheItem = ConfigChainEntryHandler.getThreadLocalCacheItem();
-            String md5 = cacheItem.getConfigCache().getMd5();
-            long lastModified = cacheItem.getConfigCache().getLastModifiedTs();
-            String encryptedDataKey = cacheItem.getConfigCache().getEncryptedDataKey();
-            String contentType = cacheItem.getType();
-            String content = ConfigDiskServiceFactory.getInstance().getContent(dataId, group, tenant);
-
-            response.setContent(content);
-            response.setMd5(md5);
-            response.setLastModified(lastModified);
-            response.setEncryptedDataKey(encryptedDataKey);
-            response.setContentType(contentType);
             response.setStatus(ConfigQueryChainResponse.ConfigQueryStatus.SPECIAL_TAG_CONFIG_NOT_FOUND);
-
             return response;
         } else {
             return nextHandler.handle(request);

config/src/main/java/com/alibaba/nacos/config/server/service/query/model/ConfigQueryChainResponse.java

@@ -32,6 +32,8 @@ public class ConfigQueryChainResponse {
 
     private String contentType;
 
+    private String configType;
+
     private String encryptedDataKey;
 
     private String md5;
@@ -89,6 +91,14 @@ public void setContentType(String contentType) {
         this.contentType = contentType;
     }
 
+    public String getConfigType() {
+        return configType;
+    }
+
+    public void setConfigType(String configType) {
+        this.configType = configType;
+    }
+
     public String getEncryptedDataKey() {
         return encryptedDataKey;
     }

config/src/test/java/com/alibaba/nacos/config/server/remote/ConfigQueryRequestHandlerTest.java

@@ -26,10 +26,10 @@
 import com.alibaba.nacos.config.server.model.gray.ConfigGrayPersistInfo;
 import com.alibaba.nacos.config.server.model.gray.GrayRuleManager;
 import com.alibaba.nacos.config.server.model.gray.TagGrayRule;
-import com.alibaba.nacos.config.server.service.query.ConfigQueryChainService;
 import com.alibaba.nacos.config.server.service.ConfigCacheService;
 import com.alibaba.nacos.config.server.service.dump.disk.ConfigDiskServiceFactory;
 import com.alibaba.nacos.config.server.service.dump.disk.ConfigRocksDbDiskService;
+import com.alibaba.nacos.config.server.service.query.ConfigQueryChainService;
 import com.alibaba.nacos.config.server.utils.GroupKey2;
 import com.alibaba.nacos.config.server.utils.PropertyUtil;
 import com.alibaba.nacos.sys.env.EnvUtil;
@@ -205,9 +205,9 @@ void testGetTagNotFound() throws Exception {
 
         //check content&md5
         assertNull(response.getContent());
-        assertEquals(MD5Utils.md5Hex(content, "UTF-8"), response.getMd5());
+        assertNull(response.getMd5());
         assertEquals(CONFIG_NOT_FOUND, response.getErrorCode());
-        assertEquals("key_testGetTag_NotFound", response.getEncryptedDataKey());
+        assertNull(response.getEncryptedDataKey());
 
         //check flags.
         assertFalse(response.isBeta());