Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you 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 org.apache.kylin.rest.controller; import java.io.IOException; import java.sql.SQLException; import java.text.SimpleDateFormat; import java.util.ArrayList; import java.util.Date; import java.util.List; import java.util.Map; import javax.servlet.http.HttpServletResponse; import org.apache.commons.io.IOUtils; import org.apache.kylin.common.debug.BackdoorToggles; import org.apache.kylin.metadata.querymeta.SelectedColumnMeta; import org.apache.kylin.metadata.querymeta.TableMeta; import org.apache.kylin.rest.exception.InternalErrorException; import org.apache.kylin.rest.model.Query; import org.apache.kylin.rest.request.MetaRequest; import org.apache.kylin.rest.request.PrepareSqlRequest; import org.apache.kylin.rest.request.SQLRequest; import org.apache.kylin.rest.request.SaveSqlRequest; import org.apache.kylin.rest.response.SQLResponse; import org.apache.kylin.rest.service.QueryService; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.beans.factory.annotation.Qualifier; import org.springframework.security.core.context.SecurityContextHolder; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.PathVariable; import org.springframework.web.bind.annotation.RequestBody; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestMethod; import org.springframework.web.bind.annotation.ResponseBody; import org.supercsv.io.CsvListWriter; import org.supercsv.io.ICsvListWriter; import org.supercsv.prefs.CsvPreference; import com.google.common.collect.Maps; /** * Handle query requests. * * @author xduo */ @Controller public class QueryController extends BasicController { @SuppressWarnings("unused") private static final Logger logger = LoggerFactory.getLogger(QueryController.class); @Autowired @Qualifier("queryService") private QueryService queryService; @RequestMapping(value = "/query", method = RequestMethod.POST, produces = { "application/json" }) @ResponseBody public SQLResponse query(@RequestBody SQLRequest sqlRequest) { return queryService.doQueryWithCache(sqlRequest); } // TODO should be just "prepare" a statement, get back expected ResultSetMetaData @RequestMapping(value = "/query/prestate", method = RequestMethod.POST, produces = "application/json") @ResponseBody public SQLResponse prepareQuery(@RequestBody PrepareSqlRequest sqlRequest) { Map<String, String> toggles = Maps.newHashMap(); toggles.put(BackdoorToggles.DEBUG_TOGGLE_PREPARE_ONLY, "true"); BackdoorToggles.addToggles(toggles); return queryService.doQueryWithCache(sqlRequest); } @RequestMapping(value = "/saved_queries", method = RequestMethod.POST, produces = { "application/json" }) @ResponseBody public void saveQuery(@RequestBody SaveSqlRequest sqlRequest) throws IOException { String creator = SecurityContextHolder.getContext().getAuthentication().getName(); Query newQuery = new Query(sqlRequest.getName(), sqlRequest.getProject(), sqlRequest.getSql(), sqlRequest.getDescription()); queryService.saveQuery(creator, newQuery); } @RequestMapping(value = "/saved_queries/{id}", method = RequestMethod.DELETE, produces = { "application/json" }) @ResponseBody public void removeQuery(@PathVariable String id) throws IOException { String creator = SecurityContextHolder.getContext().getAuthentication().getName(); queryService.removeQuery(creator, id); } @RequestMapping(value = "/saved_queries", method = RequestMethod.GET, produces = { "application/json" }) @ResponseBody public List<Query> getQueries() throws IOException { String creator = SecurityContextHolder.getContext().getAuthentication().getName(); return queryService.getQueries(creator); } @RequestMapping(value = "/query/format/{format}", method = RequestMethod.GET, produces = { "application/json" }) @ResponseBody public void downloadQueryResult(@PathVariable String format, SQLRequest sqlRequest, HttpServletResponse response) { SQLResponse result = queryService.doQueryWithCache(sqlRequest); response.setContentType("text/" + format + ";charset=utf-8"); SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMddHHmmssSSS"); Date now = new Date(); String nowStr = sdf.format(now); response.setHeader("Content-Disposition", "attachment; filename=\"" + nowStr + ".result." + format + "\""); ICsvListWriter csvWriter = null; try { csvWriter = new CsvListWriter(response.getWriter(), CsvPreference.STANDARD_PREFERENCE); List<String> headerList = new ArrayList<String>(); for (SelectedColumnMeta column : result.getColumnMetas()) { headerList.add(column.getName()); } String[] headers = new String[headerList.size()]; csvWriter.writeHeader(headerList.toArray(headers)); for (List<String> row : result.getResults()) { csvWriter.write(row); } } catch (IOException e) { throw new InternalErrorException(e); } finally { IOUtils.closeQuietly(csvWriter); } } @RequestMapping(value = "/tables_and_columns", method = RequestMethod.GET, produces = { "application/json" }) @ResponseBody public List<TableMeta> getMetadata(MetaRequest metaRequest) { try { return queryService.getMetadata(metaRequest.getProject()); } catch (SQLException e) { throw new InternalErrorException(e.getLocalizedMessage(), e); } } public void setQueryService(QueryService queryService) { this.queryService = queryService; } }