bejancsaba commented on code in PR #6075: URL: https://github.com/apache/nifi/pull/6075#discussion_r899966740
########## minifi/minifi-bootstrap/src/main/java/org/apache/nifi/minifi/bootstrap/service/MiNiFiCommandSender.java: ########## @@ -0,0 +1,131 @@ +/* + * 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.nifi.minifi.bootstrap.service; + +import com.fasterxml.jackson.core.JsonProcessingException; +import com.fasterxml.jackson.databind.ObjectMapper; +import java.io.BufferedReader; +import java.io.EOFException; +import java.io.IOException; +import java.io.InputStreamReader; +import java.io.OutputStream; +import java.net.InetSocketAddress; +import java.net.Socket; +import java.net.SocketTimeoutException; +import java.nio.charset.StandardCharsets; +import java.util.Arrays; +import java.util.Optional; +import java.util.stream.Collectors; +import org.apache.nifi.minifi.bootstrap.MiNiFiParameters; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +public class MiNiFiCommandSender { + + private static final Logger LOGGER = LoggerFactory.getLogger(MiNiFiCommandSender.class); + private static final String PING_CMD = "PING"; + private static final int SOCKET_TIMEOUT = 10000; + private static final int CONNECTION_TIMEOUT = 10000; + + private final MiNiFiParameters miNiFiParameters; + private final ObjectMapper objectMapper; + + public MiNiFiCommandSender(MiNiFiParameters miNiFiParameters, ObjectMapper objectMapper) { + this.miNiFiParameters = miNiFiParameters; + this.objectMapper = objectMapper; + } + + public Optional<String> sendCommand(String cmd, Integer port, String... extraParams) throws IOException { + Optional<String> response = Optional.empty(); + + if (port == null) { + LOGGER.info("Apache MiNiFi is not currently running"); + return response; + } + + try (Socket socket = new Socket()) { + LOGGER.debug("Connecting to MiNiFi instance"); + socket.setSoTimeout(SOCKET_TIMEOUT); + socket.connect(new InetSocketAddress("localhost", port), CONNECTION_TIMEOUT); + LOGGER.debug("Established connection to MiNiFi instance."); + + LOGGER.debug("Sending {} Command to port {}", cmd, port); + + String responseString; + try (OutputStream out = socket.getOutputStream()) { + out.write(getCommand(cmd, extraParams)); + out.flush(); + responseString = readResponse(socket); + } + + LOGGER.debug("Received response to {} command: {}", cmd, responseString); + response = Optional.of(responseString); + } catch (EOFException | SocketTimeoutException e) { + String message = "Failed to get response for " + cmd + " Potentially due to the process currently being down (restarting or otherwise)"; + throw new RuntimeException(message); + } + return response; + } + + <T> T sendCommandForObject(String cmd, Integer port, Class<T> clazz, String... extraParams) throws IOException { + return sendCommand(cmd, port, extraParams) + .map(response -> deserialize(cmd, response, clazz)) + .orElse(null); + } + + private String readResponse(Socket socket) throws IOException { + StringBuilder sb = new StringBuilder(); + int numLines = 0; + try (BufferedReader reader = new BufferedReader(new InputStreamReader(socket.getInputStream()))) { + String line; + while ((line = reader.readLine()) != null) { + if (numLines++ > 0) { + sb.append("\n"); + } + sb.append(line); + } + } + + return sb.toString().trim(); + } + + private byte[] getCommand(String cmd, String... args) { + String argsString = Arrays.stream(args).collect(Collectors.joining(" ")); + String commandWithArgs = cmd + " " + miNiFiParameters.getSecretKey() + (args.length > 0 ? " " : "") + argsString + "\n"; + return commandWithArgs.getBytes(StandardCharsets.UTF_8); + } + + private <T> T deserialize(String cmd, String obj, Class<T> clazz) { + T response; + try { + response = objectMapper.readValue(obj, clazz); + } catch (JsonProcessingException e) { + String message = "Failed to deserialize " + cmd + " response"; + LOGGER.error(message); + throw new RuntimeException(message); Review Comment: Added -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
