聊聊PowerJob的OmsLogHandler

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本文主要研究一下PowerJob的OmsLogHandler

OmsLogHandler

tech/powerjob/worker/background/OmsLogHandler.java

@Slf4j
public class OmsLogHandler {

    private final String workerAddress;
    private final Transporter transporter;
    private final ServerDiscoveryService serverDiscoveryService;

    // 处理线程，需要通过线程池启动
    public final Runnable logSubmitter = new LogSubmitter();
    // 上报锁，只需要一个线程上报即可
    private final Lock reportLock = new ReentrantLock();
    // 生产者消费者模式，异步上传日志
    private final BlockingQueue<InstanceLogContent> logQueue = Queues.newLinkedBlockingQueue(10240);

    // 每次上报携带的数据条数
    private static final int BATCH_SIZE = 20;
    // 本地囤积阈值
    private static final int REPORT_SIZE = 1024;

    public OmsLogHandler(String workerAddress, Transporter transporter, ServerDiscoveryService serverDiscoveryService) {
        this.workerAddress = workerAddress;
        this.transporter = transporter;
        this.serverDiscoveryService = serverDiscoveryService;
    }

    /**
     * 提交日志
     * @param instanceId 任务实例ID
     * @param logContent 日志内容
     */
    public void submitLog(long instanceId, LogLevel logLevel, String logContent) {

        if (logQueue.size() > REPORT_SIZE) {
            // 线程的生命周期是个不可循环的过程，一个线程对象结束了不能再次start，只能一直创建和销毁
            new Thread(logSubmitter).start();
        }

        InstanceLogContent tuple = new InstanceLogContent(instanceId, System.currentTimeMillis(), logLevel.getV(), logContent);
        boolean offerRet = logQueue.offer(tuple);
        if (!offerRet) {
            log.warn("[OmsLogHandler] [{}] submit log failed, maybe your log speed is too fast!", instanceId);
        }
    }

    //......
}    

OmsLogHandler提供了submitLog方法，它先判断logQueue大小是否超过REPORT_SIZE(1024)，超过则通过异步线程执行logSubmitter；接着将内容包装为InstanceLogContent，然后放入到logQueue

LogSubmitter

    private class LogSubmitter implements Runnable {

        @Override
        public void run() {

            boolean lockResult = reportLock.tryLock();
            if (!lockResult) {
                return;
            }

            try {

                final String currentServerAddress = serverDiscoveryService.getCurrentServerAddress();
                // 当前无可用 Server
                if (StringUtils.isEmpty(currentServerAddress)) {
                    if (!logQueue.isEmpty()) {
                        logQueue.clear();
                        log.warn("[OmsLogHandler] because there is no available server to report logs which leads to queue accumulation, oms discarded all logs.");
                    }
                    return;
                }

                List<InstanceLogContent> logs = Lists.newLinkedList();

                while (!logQueue.isEmpty()) {
                    try {
                        InstanceLogContent logContent = logQueue.poll(100, TimeUnit.MILLISECONDS);
                        logs.add(logContent);

                        if (logs.size() >= BATCH_SIZE) {
                            WorkerLogReportReq req = new WorkerLogReportReq(workerAddress, Lists.newLinkedList(logs));
                            // 不可靠请求，WEB日志不追求极致
                            TransportUtils.reportLogs(req, currentServerAddress, transporter);
                            logs.clear();
                        }

                    }catch (Exception ignore) {
                        break;
                    }
                }

                if (!logs.isEmpty()) {
                    WorkerLogReportReq req = new WorkerLogReportReq(workerAddress, logs);
                    TransportUtils.reportLogs(req, currentServerAddress, transporter);
                }

            }finally {
                reportLock.unlock();
            }
        }
    }

LogSubmitter实现了Runnable接口，其run方法先通过reportLock加锁，成功才继续，它通过serverDiscoveryService.getCurrentServerAddress()获取当前server的地址，若获取不到则清空logQueue；否则while循环，每次从logQueue拉取InstanceLogContent，放到linkedList，超过BATCH_SIZE(20)则创建WorkerLogReportReq，通过TransportUtils.reportLogs(req, currentServerAddress, transporter)上报，然后清空linkedList，跳出循环之后再上报剩下的日志，最后释放锁

reportLogs

tech/powerjob/worker/common/utils/TransportUtils.java

    public static void reportLogs(WorkerLogReportReq req, String address, Transporter transporter) {
        final URL url = easyBuildUrl(ServerType.SERVER, S4W_PATH, S4W_HANDLER_REPORT_LOG, address);
        transporter.tell(url, req);
    }

    public static URL easyBuildUrl(ServerType serverType, String rootPath, String handlerPath, String address) {
        HandlerLocation handlerLocation = new HandlerLocation()
                .setRootPath(rootPath)
                .setMethodPath(handlerPath);
        return new URL()
                .setServerType(serverType)
                .setAddress(Address.fromIpv4(address))
                .setLocation(handlerLocation);
    }    

reportLogs先通过easyBuildUrl构建URL，再通过transporter.tell(url, req)发送请求，rootPath为server，handlerPath为reportLog

tell

AkkaTransporter

tech/powerjob/remote/akka/AkkaTransporter.java

    public void tell(URL url, PowerSerializable request) {
        ActorSelection actorSelection = fetchActorSelection(url);
        actorSelection.tell(request, null);
    }

AkkaTransporter直接使用actorSelection发送请求

VertxTransporter

tech/powerjob/remote/http/vertx/VertxTransporter.java

    public void tell(URL url, PowerSerializable request) {
        post(url, request, null);
    }

    private <T> CompletionStage<T> post(URL url, PowerSerializable request, Class<T> clz) {
        final String host = url.getAddress().getHost();
        final int port = url.getAddress().getPort();
        final String path = url.getLocation().toPath();
        RequestOptions requestOptions = new RequestOptions()
                .setMethod(HttpMethod.POST)
                .setHost(host)
                .setPort(port)
                .setURI(path);
        // 获取远程服务器的HTTP连接
        Future<HttpClientRequest> httpClientRequestFuture = httpClient.request(requestOptions);
        // 转换 -> 发送请求获取响应
        Future<HttpClientResponse> responseFuture = httpClientRequestFuture.compose(httpClientRequest ->
            httpClientRequest
                .putHeader(HttpHeaderNames.CONTENT_TYPE, HttpHeaderValues.APPLICATION_JSON)
                .send(JsonObject.mapFrom(request).toBuffer())
        );
        return responseFuture.compose(httpClientResponse -> {
            // throw exception
            final int statusCode = httpClientResponse.statusCode();
            if (statusCode != HttpResponseStatus.OK.code()) {
                // CompletableFuture.get() 时会传递抛出该异常
                throw new RemotingException(String.format("request [host:%s,port:%s,url:%s] failed, status: %d, msg: %s",
                       host, port, path, statusCode, httpClientResponse.statusMessage()
                        ));
            }

            return httpClientResponse.body().compose(x -> {

                if (clz == null) {
                    return Future.succeededFuture(null);
                }

                if (clz.equals(String.class)) {
                    return Future.succeededFuture((T) x.toString());
                }

                return Future.succeededFuture(x.toJsonObject().mapTo(clz));
            });
        }).toCompletionStage();
    }    

VertxTransporter则使用post方法通过vertx的httpClient发送请求

processWorkerLogReport

tech/powerjob/server/core/handler/AbWorkerRequestHandler.java

    @Handler(path = S4W_HANDLER_REPORT_LOG, processType = ProcessType.NO_BLOCKING)
    public void processWorkerLogReport(WorkerLogReportReq req) {

        WorkerLogReportEvent event = new WorkerLogReportEvent()
                .setWorkerAddress(req.getWorkerAddress())
                .setLogNum(req.getInstanceLogContents().size());
        try {
            processWorkerLogReport0(req, event);
            event.setStatus(WorkerLogReportEvent.Status.SUCCESS);
        } catch (RejectedExecutionException re) {
            event.setStatus(WorkerLogReportEvent.Status.REJECTED);
        } catch (Throwable t) {
            event.setStatus(WorkerLogReportEvent.Status.EXCEPTION);
            log.warn("[WorkerRequestHandler] process worker report failed!", t);
        } finally {
            monitorService.monitor(event);
        }
    }

processWorkerLogReport通过processWorkerLogReport0进行处理，最后通过monitorService.monitor(event)上报监控

processWorkerLogReport0

tech/powerjob/server/core/handler/WorkerRequestHandlerImpl.java

    @Override
    protected void processWorkerLogReport0(WorkerLogReportReq req, WorkerLogReportEvent event) {
        // 这个效率应该不会拉垮吧...也就是一些判断 + Map#get 吧...
        instanceLogService.submitLogs(req.getWorkerAddress(), req.getInstanceLogContents());
    }

processWorkerLogReport0通过instanceLogService.submitLogs进行上报

submitLogs

tech/powerjob/server/core/instance/InstanceLogService.java

    /**
     * 提交日志记录，持久化到本地数据库中
     * @param workerAddress 上报机器地址
     * @param logs 任务实例运行时日志
     */
    @Async(value = PJThreadPool.LOCAL_DB_POOL)
    public void submitLogs(String workerAddress, List<InstanceLogContent> logs) {

        List<LocalInstanceLogDO> logList = logs.stream().map(x -> {
            instanceId2LastReportTime.put(x.getInstanceId(), System.currentTimeMillis());

            LocalInstanceLogDO y = new LocalInstanceLogDO();
            BeanUtils.copyProperties(x, y);
            y.setWorkerAddress(workerAddress);
            return y;
        }).collect(Collectors.toList());

        try {
            CommonUtils.executeWithRetry0(() -> localInstanceLogRepository.saveAll(logList));
        }catch (Exception e) {
            log.warn("[InstanceLogService] persistent instance logs failed, these logs will be dropped: {}.", logs, e);
        }
    }

InstanceLogService通过PJThreadPool.LOCAL_DB_POOL线程池进行异步，它通过localInstanceLogRepository.saveAll(logList)保存到本地数据库

monitor

tech/powerjob/server/monitor/PowerJobMonitorService.java

    public void monitor(Event event) {
        monitors.forEach(m -> m.record(event));
    }

monitor方法遍历monitors，挨个执行record

LogMonitor

tech/powerjob/server/monitor/monitors/LogMonitor.java

    public void record(Event event) {
        MDC.put(MDC_KEY_SERVER_ID, String.valueOf(serverInfo.getId()));
        LoggerFactory.getLogger(event.type()).info(event.message());
    }

LogMonitor的record方法通过日志打印event信息

小结

PowerJob的OmsLogHandler提供了submitLog方法，它先判断logQueue大小是否超过REPORT_SIZE(1024)，超过则通过异步线程执行logSubmitter；接着将内容包装为InstanceLogContent，然后放入到logQueue；logSubmitter主要是执行reportLogs，它先通过easyBuildUrl构建URL，再通过transporter.tell(url, req)发送请求，rootPath为server，handlerPath为reportLog；服务端的processWorkerLogReport通过processWorkerLogReport0进行处理(通过localInstanceLogRepository.saveAll(logList)保存到本地数据库)，最后通过monitorService.monitor(event)上报监控。