| /* |
| * 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.drill.test; |
| |
| import java.util.concurrent.BlockingQueue; |
| |
| import org.apache.drill.common.exceptions.UserException; |
| import org.apache.drill.exec.proto.UserBitShared.QueryId; |
| import org.apache.drill.exec.proto.UserBitShared.QueryResult.QueryState; |
| import org.apache.drill.exec.rpc.ConnectionThrottle; |
| import org.apache.drill.exec.rpc.user.QueryDataBatch; |
| import org.apache.drill.exec.rpc.user.UserResultsListener; |
| |
| import org.apache.drill.shaded.guava.com.google.common.collect.Queues; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| /** |
| * Drill query event listener that buffers rows into a producer-consumer |
| * queue. Allows rows to be received asynchronously, but processed by |
| * a synchronous reader. |
| * <p> |
| * Query messages are transformed into events: query ID, batch, |
| * EOF or error. |
| */ |
| public class BufferingQueryEventListener implements UserResultsListener { |
| private static final Logger logger = LoggerFactory.getLogger(BufferingQueryEventListener.class); |
| |
| public static class QueryEvent { |
| public enum Type { QUERY_ID, BATCH, EOF, ERROR } |
| |
| public final Type type; |
| public QueryId queryId; |
| public QueryDataBatch batch; |
| public Exception error; |
| public QueryState state; |
| |
| public QueryEvent(QueryId queryId) { |
| this.queryId = queryId; |
| this.type = Type.QUERY_ID; |
| } |
| |
| public QueryEvent(Exception ex) { |
| error = ex; |
| type = Type.ERROR; |
| } |
| |
| public QueryEvent(QueryDataBatch batch) { |
| this.batch = batch; |
| type = Type.BATCH; |
| } |
| |
| public QueryEvent(QueryState state) { |
| this.type = Type.EOF; |
| this.state = state; |
| } |
| } |
| |
| private final BlockingQueue<QueryEvent> queue = Queues.newLinkedBlockingQueue(); |
| |
| @Override |
| public void queryIdArrived(QueryId queryId) { |
| silentPut(new QueryEvent(queryId)); |
| } |
| |
| @Override |
| public void submissionFailed(UserException ex) { |
| silentPut(new QueryEvent(ex)); |
| } |
| |
| @Override |
| public void dataArrived(QueryDataBatch result, ConnectionThrottle throttle) { |
| silentPut(new QueryEvent(result)); |
| } |
| |
| @Override |
| public void queryCompleted(QueryState state) { |
| silentPut(new QueryEvent(state)); |
| } |
| |
| private void silentPut(QueryEvent event) { |
| try { |
| queue.put(event); |
| } catch (InterruptedException e) { |
| logger.error("Exception:", e); |
| } |
| } |
| |
| public QueryEvent get() { |
| try { |
| return queue.take(); |
| } catch (InterruptedException e) { |
| // Should not occur, but if it does, just pass along the error. |
| return new QueryEvent(e); |
| } |
| } |
| } |