| /* |
| * 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.calcite.avatica.remote; |
| |
| import org.apache.calcite.avatica.AvaticaUtils; |
| |
| import java.io.DataOutputStream; |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.net.HttpURLConnection; |
| import java.net.URL; |
| |
| /** |
| * A common class to invoke HTTP requests against the Avatica server agnostic of the data being |
| * sent and received across the wire. |
| */ |
| public class AvaticaHttpClientImpl implements AvaticaHttpClient { |
| protected final URL url; |
| |
| public AvaticaHttpClientImpl(URL url) { |
| this.url = url; |
| } |
| |
| public byte[] send(byte[] request) { |
| // TODO back-off policy? |
| while (true) { |
| try { |
| final HttpURLConnection connection = openConnection(); |
| connection.setRequestMethod("POST"); |
| connection.setDoInput(true); |
| connection.setDoOutput(true); |
| try (DataOutputStream wr = new DataOutputStream(connection.getOutputStream())) { |
| wr.write(request); |
| wr.flush(); |
| wr.close(); |
| } |
| final int responseCode = connection.getResponseCode(); |
| final InputStream inputStream; |
| if (responseCode == HttpURLConnection.HTTP_UNAVAILABLE) { |
| // Could be sitting behind a load-balancer, try again. |
| continue; |
| } else if (responseCode != HttpURLConnection.HTTP_OK) { |
| inputStream = connection.getErrorStream(); |
| if (inputStream == null) { |
| // HTTP Transport exception that resulted in no content coming back |
| throw new RuntimeException("Failed to read data from the server: HTTP/" + responseCode); |
| } |
| } else { |
| inputStream = connection.getInputStream(); |
| } |
| return AvaticaUtils.readFullyToBytes(inputStream); |
| } catch (IOException e) { |
| throw new RuntimeException(e); |
| } |
| } |
| } |
| |
| HttpURLConnection openConnection() throws IOException { |
| return (HttpURLConnection) url.openConnection(); |
| } |
| } |
| |
| // End AvaticaHttpClientImpl.java |