View Javadoc
1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *     http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  
18  package org.apache.shardingsphere.proxy.backend.mysql.handler.admin.executor;
19  
20  import lombok.Getter;
21  import org.apache.shardingsphere.authority.rule.AuthorityRule;
22  import org.apache.shardingsphere.infra.executor.sql.execute.result.query.QueryResultMetaData;
23  import org.apache.shardingsphere.infra.executor.sql.execute.result.query.impl.raw.metadata.RawQueryResultColumnMetaData;
24  import org.apache.shardingsphere.infra.executor.sql.execute.result.query.impl.raw.metadata.RawQueryResultMetaData;
25  import org.apache.shardingsphere.infra.merge.result.MergedResult;
26  import org.apache.shardingsphere.infra.merge.result.impl.local.LocalDataMergedResult;
27  import org.apache.shardingsphere.infra.merge.result.impl.local.LocalDataQueryResultRow;
28  import org.apache.shardingsphere.infra.metadata.user.Grantee;
29  import org.apache.shardingsphere.infra.metadata.user.ShardingSphereUser;
30  import org.apache.shardingsphere.proxy.backend.context.ProxyContext;
31  import org.apache.shardingsphere.proxy.backend.handler.admin.executor.DatabaseAdminQueryExecutor;
32  import org.apache.shardingsphere.proxy.backend.session.ConnectionSession;
33  
34  import java.sql.Types;
35  import java.util.Collections;
36  import java.util.Optional;
37  
38  /**
39   * Show current user executor.
40   */
41  @Getter
42  public final class ShowCurrentUserExecutor implements DatabaseAdminQueryExecutor {
43      
44      public static final String FUNCTION_NAME = "current_user()";
45      
46      public static final String FUNCTION_NAME_ALIAS = "current_user";
47      
48      private MergedResult mergedResult;
49      
50      @Override
51      public void execute(final ConnectionSession connectionSession) {
52          AuthorityRule authorityRule = ProxyContext.getInstance().getContextManager().getMetaDataContexts().getMetaData().getGlobalRuleMetaData().getSingleRule(AuthorityRule.class);
53          Optional<Grantee> grantee = authorityRule.findUser(connectionSession.getGrantee()).map(ShardingSphereUser::getGrantee);
54          mergedResult = new LocalDataMergedResult(Collections.singleton(new LocalDataQueryResultRow(grantee.isPresent() ? grantee.get().toString() : "")));
55      }
56      
57      @Override
58      public QueryResultMetaData getQueryResultMetaData() {
59          return new RawQueryResultMetaData(Collections.singletonList(new RawQueryResultColumnMetaData("", FUNCTION_NAME, FUNCTION_NAME, Types.VARCHAR, "VARCHAR", 100, 0)));
60      }
61  }