Github user zentol commented on a diff in the pull request:
https://github.com/apache/flink/pull/3460#discussion_r104635328
--- Diff:
flink-runtime-web/src/main/java/org/apache/flink/runtime/webmonitor/history/HistoryServer.java
---
@@ -0,0 +1,411 @@
+/*
+ * 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.flink.runtime.webmonitor.history;
+
+import com.fasterxml.jackson.core.JsonFactory;
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import io.netty.handler.codec.http.router.Router;
+import org.apache.flink.api.java.utils.ParameterTool;
+import org.apache.flink.configuration.Configuration;
+import org.apache.flink.configuration.GlobalConfiguration;
+import org.apache.flink.configuration.HistoryServerOptions;
+import org.apache.flink.core.fs.FileStatus;
+import org.apache.flink.core.fs.FileSystem;
+import org.apache.flink.core.fs.Path;
+import org.apache.flink.runtime.filecache.FileCache;
+import org.apache.flink.runtime.net.SSLUtils;
+import org.apache.flink.runtime.util.ExecutorThreadFactory;
+import
org.apache.flink.runtime.webmonitor.handlers.CurrentJobsOverviewHandler;
+import org.apache.flink.runtime.webmonitor.handlers.DashboardConfigHandler;
+import org.apache.flink.runtime.webmonitor.utils.NettySetup;
+import org.apache.flink.util.FileUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import javax.net.ssl.SSLContext;
+import java.io.File;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.TimerTask;
+import java.util.UUID;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.TimeUnit;
+
+public class HistoryServer {
+
+ private static final Logger LOG =
LoggerFactory.getLogger(HistoryServer.class);
+ private static final JsonFactory jacksonFactory = new JsonFactory();
+ private static final ObjectMapper mapper = new ObjectMapper();
+
+ private static final String OVERVIEWS_FOLDER_NAME = "overviews";
+
+ private final String webAddress;
+ private final int webPort;
+ private final long webRefreshIntervalMillis;
+ private final File webDir;
+
+ private final long refreshIntervalMillis;
+ private final List<Path> refreshDirs = new ArrayList<>();
+
+ /** Map containing the JobID of all fetched jobs and the refreshDir
from with they originate. */
+ private final Map<String, Path> cachedArchives = new
ConcurrentHashMap<>();
+
+ private final SSLContext serverSSLContext;
+ private NettySetup netty;
+ private final Object startupShutdownLock = new Object();
+
+ private final ScheduledExecutorService executor =
Executors.newSingleThreadScheduledExecutor(
+ new ExecutorThreadFactory("Flink-HistoryServer-FileFetcher"));
+ private final JobArchiveFetcherTask fetcherTask;
+
+ public static void main(String[] args) throws Exception {
+ ParameterTool pt = ParameterTool.fromArgs(args);
+ String configDir = pt.getRequired("configDir");
+
+ LOG.info("Loading configuration from {}", configDir);
+ Configuration flinkConfig =
GlobalConfiguration.loadConfiguration(configDir);
+
+ HistoryServer hs = new HistoryServer(flinkConfig);
+ hs.run();
+ }
+
+ public HistoryServer(Configuration config) throws IOException {
+ if
(config.getBoolean(HistoryServerOptions.HISTORY_SERVER_WEB_SSL_ENABLED) &&
SSLUtils.getSSLEnabled(config)) {
+ LOG.info("Enabling ssl for the history server.");
+ try {
+ this.serverSSLContext =
SSLUtils.createSSLServerContext(config);
+ } catch (Exception e) {
+ throw new IOException("Failed to initialize
SSLContext for the history server.", e);
+ }
+ } else {
+ this.serverSSLContext = null;
+ }
+
+ webAddress =
config.getString(HistoryServerOptions.HISTRY_SERVER_WEB_ADDRESS);
+ webPort =
config.getInteger(HistoryServerOptions.HISTORY_SERVER_WEB_PORT);
+ webRefreshIntervalMillis =
config.getLong(HistoryServerOptions.HISTORY_SERVER_WEB_REFRESH_INTERVAL);
+
+ String webDirectory =
config.getString(HistoryServerOptions.HISTORY_SERVER_WEB_DIR);
+ if (webDirectory == null) {
+ webDirectory = System.getProperty("java.io.tmpdir") +
"flink-web-history-" + UUID.randomUUID();
+ }
+ webDir = new File(webDirectory);
+
+ String refreshDirectories =
config.getString(HistoryServerOptions.HISTORY_SERVER_DIR);
+ if (refreshDirectories == null) {
+ throw new
IOException(HistoryServerOptions.HISTORY_SERVER_DIR + " was not configured.");
+ }
+ for (String refreshDirectory : refreshDirectories.split(",")) {
+ refreshDirs.add(new Path(refreshDirectory));
+ }
+ refreshIntervalMillis =
config.getLong(HistoryServerOptions.HISTORY_SERVER_REFRESH_INTERVAL);
+
+ this.fetcherTask = new JobArchiveFetcherTask(refreshDirs,
cachedArchives, webDir);
+
+ // add shutdown hook for deleting the directories and remaining
temp files on shutdown
+ try {
+ Runtime.getRuntime().addShutdownHook(new Thread() {
+ @Override
+ public void run() {
+ HistoryServer.this.stop();
+ }
+ });
+ } catch (IllegalStateException e) {
+ // race, JVM is in shutdown already, we can safely
ignore this
+ LOG.debug("Unable to add shutdown hook, shutdown
already in progress", e);
+ } catch (Throwable t) {
+ // these errors usually happen when the shutdown is
already in progress
+ LOG.warn("Error while adding shutdown hook", t);
+ }
+ }
+
+ public void run() {
+ try {
+ start();
+ while (true) {
+ try {
+ new CountDownLatch(1).await();
+ } catch (InterruptedException e) {
+ Thread.currentThread().interrupt();
+ }
+ }
+ } catch (Exception e) {
+ LOG.error("Failure while running HistoryServer.", e);
+ } finally {
+ stop();
+ }
+ }
+
+ //
=================================================================================================================
+ // Life-cycle
+ //
=================================================================================================================
+ private void start() throws IOException, InterruptedException {
+ synchronized (startupShutdownLock) {
+ LOG.info("Starting history server.");
+
+ Files.createDirectories(webDir.toPath());
+ LOG.info("Using directory {} as local cache.", webDir);
+ if (LOG.isInfoEnabled()) {
+ for (Path refreshDir : refreshDirs) {
+ LOG.info("Monitoring directory {} for
archived jobs.", refreshDir);
+ }
+ }
+
+ Router router = new Router();
+ router.GET("/:*", new
HistoryServerStaticFileServerHandler(webDir, new JobFileFetcher(new
Path(webDir.getAbsolutePath()), cachedArchives)));
+
+ netty = new NettySetup(router, LOG, webDir,
serverSSLContext, webAddress, webPort);
+
+ createDashboardConfigFile();
+ updateJobOverview(webDir);
+
+ executor.scheduleWithFixedDelay(fetcherTask,
refreshIntervalMillis, refreshIntervalMillis, TimeUnit.MILLISECONDS);
+ }
+ }
+
+ private void stop() {
+ synchronized (startupShutdownLock) {
+ LOG.info("Stopping history server.");
+ netty.shutdown();
+ shutdownExecutor();
+ try {
+ LOG.info("Removing web dashboard root cache
directory {}", webDir);
+ FileUtils.deleteDirectory(webDir);
+ } catch (Throwable t) {
+ LOG.warn("Error while deleting web root
directory {}", webDir, t);
+ }
+
+ LOG.info("Stopped history server.");
+ }
+ }
+
+ private void shutdownExecutor() {
+ if (executor != null) {
+ executor.shutdown();
+
+ try {
+ if (!executor.awaitTermination(1,
TimeUnit.SECONDS)) {
+ executor.shutdownNow();
+ }
+ } catch (InterruptedException ignored) {
+ executor.shutdownNow();
+ }
+ }
+ }
+
+ //
=================================================================================================================
+ // File-fetching
+ //
=================================================================================================================
+
+ /**
+ * {@link TimerTask} that polls the directories configured as {@link
HistoryServerOptions#HISTORY_SERVER_DIR} for
+ * new job archives.
+ */
+ private static class JobArchiveFetcherTask extends TimerTask {
+ private final List<Path> refreshDirs;
+ private final Map<String, Path> cachedArchives;
+ private final File webDir;
+ private final Path webJobDir;
+ private final Path webOverviewDir;
+
+ public JobArchiveFetcherTask(List<Path> refreshDirs,
Map<String, Path> cachedArchives, File webDir) {
+ this.refreshDirs = refreshDirs;
+ this.cachedArchives = cachedArchives;
+ this.webDir = webDir;
+ this.webJobDir = new Path(webDir.getAbsolutePath(),
"jobs");
+ this.webOverviewDir = new
Path(webDir.getAbsolutePath(), OVERVIEWS_FOLDER_NAME);
+ }
+
+ @Override
+ public void run() {
+ for (Iterator<Path> iterator = refreshDirs.iterator();
iterator.hasNext();) {
+ Path refreshDir = iterator.next();
+ FileSystem fs;
+ try {
+ fs = refreshDir.getFileSystem();
+ } catch (IOException e) {
+ LOG.error("Failed to create FileSystem
for path {}.", refreshDir, e);
+ // there's most likely something wrong
with the path itself
+ try {
+ iterator.remove();
+ } catch (Exception ignored) {
+ //well, we tried
+ }
+ continue;
+ }
+
+ /**
+ * The expected directory structure is as
follows:
+ * /:refreshDir/:jobid/jobs/:jobid/...
+ * /:refreshDir/:jobid/jobs/:jobid.json
+ * /:refreshDir/:jobid/joboverview.json
+ */
+ // contents of /:refreshDir
+ FileStatus[] jobArchives;
+ try {
+ jobArchives = fs.listStatus(refreshDir);
+ } catch (IOException e) {
+ LOG.error("Failed to access job archive
location for path {}.", refreshDir, e);
+ continue;
+ }
+ boolean updateOverview = false;
+ for (FileStatus jobArchive : jobArchives) {
+ Path jobArchivePath =
jobArchive.getPath();
+ String jobID = jobArchivePath.getName();
+ if (cachedArchives.put(jobID,
refreshDir) == null) {
+ try {
+ // contents of
/:refreshDir/:jobid
+ FileStatus[]
archiveFiles = fs.listStatus(jobArchivePath);
+ for (FileStatus
archiveFile : archiveFiles) {
+ if
(archiveFile.isDir()) {
+ //
contents of /:refreshDir/:jobid/jobs
+ for
(FileStatus jobFile : fs.listStatus(archiveFile.getPath())) {
+
/**
+
* src: /:refreshDir/:jobid/jobs/X
+
* dst: /:webDir/jobs/X
+
*
+
* X is either :jobid.json or the :jobid directory.
+
*/
+
FileCache.copy(jobFile.getPath(), new Path(webJobDir + "/" +
jobFile.getPath().getName()), false);
+ }
+ } else {
+ /**
+ * src:
/:refreshDir/:jobid/joboverview.json
+ * dst:
/:webDir/joboverviews/:jobid.json
+ */
+
FileCache.copy(archiveFile.getPath(), new Path(webOverviewDir, jobID +
".json"), false);
+
updateOverview = true;
+ }
+ }
+ } catch (IOException e) {
+ LOG.error("Failed to
fetch archive file.", e);
+
cachedArchives.remove(jobID);
+ continue;
+ }
+ }
+ }
+ if (updateOverview) {
+ updateJobOverview(webDir);
+ }
+ }
+ }
+ }
+
+ /**
+ * Backup file fetcher that is used by the {@link
HistoryServerStaticFileServerHandler} if it cannot find a file
+ * within a job archive. This class does not share code with the {@link
JobArchiveFetcherTask} since the former
+ * fetches entire archives at a given location based on a path whereas
this class only fetches one specific file
+ * based on a REST URL.
+ */
+ public static class JobFileFetcher {
+ private final Path webDir;
+ private final Map<String, Path> cachedArchives;
+
+ public JobFileFetcher(Path webDir, Map<String, Path>
cachedArchives) {
+ this.webDir = webDir;
+ this.cachedArchives = cachedArchives;
+ }
+
+ public void fetchFileForRestRequest(String requestPath) throws
IOException {
+ /**
+ * Here we extract the job ID from the request path. We
are either missing a file that resides
+ * under /jobs/:jobid/* or /jobs/:jobid.json. In the
latter case indexOf will
+ * return -1 so we manually set 'to' to the index
before '.json'.
+ */
+ int from = 6;
+ int to = requestPath.indexOf('/', 7);
+ if (to == -1) {
+ to = requestPath.length() - 5;
+ }
+ String jobID = requestPath.substring(from, to);
+ Path sourcePath = new Path(new
Path(cachedArchives.get(jobID), jobID), requestPath);
+ try {
+ FileCache.copy(sourcePath, new Path(webDir,
requestPath), false);
+ } catch (Exception e) {
+ LOG.debug("Failed to retrieve file {} for job
{}. This may indicate an incomplete or corrupt job archive.", sourcePath, e);
+ LOG.error("Failed to retrieve file {} for job
{}. This may indicate an incomplete or corrupt job archive.", sourcePath,
jobID);
+ }
+ }
+ }
+
+ //
=================================================================================================================
+ // File generation
+ //
=================================================================================================================
+ private static FileWriter createOrGetFile(File folder, String name)
throws IOException {
+ File file = new File(folder, name + ".json");
+ if (!file.exists()) {
+ Files.createFile(file.toPath());
+ }
+ FileWriter fr = new FileWriter(file);
+ return fr;
+ }
+
+ private void createDashboardConfigFile() throws IOException {
+ try (FileWriter fw = createOrGetFile(webDir, "config")) {
+
fw.write(DashboardConfigHandler.createConfigJson(webRefreshIntervalMillis));
+ fw.flush();
+ } catch (IOException ioe) {
+ LOG.error("Failed to write config file.");
+ throw ioe;
+ }
+ }
+
+ /**
+ * This method replicates the JSON response that would be given by the
{@link CurrentJobsOverviewHandler} when
+ * listing both running and finished jobs.
+ *
+ * Every job archive contains a joboverview.json file containing the
same structure. Since jobs are archived on
+ * their own however the list of finished jobs only contains a single
job.
+ *
+ * For the display in the HistoryServer WebFrontend we have to combine
these overviews.
+ */
+ private static void updateJobOverview(File webDir) {
--- End diff --
The CurrentJobsOverhandler is hard-wired to use akka; it sends a
```RequestJobDetails``` request. Dealing with that is more complicated than the
current approach.
We could add a new in-memory handler for this though. The entire
implementation would be basically the ```updateJobOverview``` method; without
the file writing.
---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at infrastruct...@apache.org or file a JIRA ticket
with INFRA.
---
