package org.lokra.weed;
import feign.Feign;
import feign.jackson.JacksonDecoder;
import feign.okhttp.OkHttpClient;
import org.lokra.weed.content.Cluster;
import org.lokra.weed.content.Locations;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.HashSet;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import java.util.stream.Collectors;
public class WeedManager {
private final Logger log = LoggerFactory.getLogger(WeedManager.class);
private ConcurrentMap<String, WeedVolumeClient> volumeClients = new ConcurrentHashMap<>();
private ConcurrentMap<String, Set<String>> volumeCollectionIds = new ConcurrentHashMap<>();
private ConcurrentMap<String, WeedMasterClient> peerMasters = new ConcurrentHashMap<>();
private final MasterHealthCheckThread masterHealthCheckThread = new MasterHealthCheckThread();
private final VolumeHealthCheckThread volumeHealthCheckThread = new VolumeHealthCheckThread();
private String leaderMasterUrl;
private WeedMasterClient leaderMaster;
private String host;
private int port;
public WeedManager() {
}
/**
* Construction.
*
* @param host Master server host.
* @param port Master server port.
*/
public WeedManager(String host, int port) {
this.host = host;
this.port = port;
}
/**
* Startup weed manager.
*/
public void start() {
leaderMasterUrl = assembleUrl(host, port);
leaderMaster = Feign.builder()
.client(new OkHttpClient())
.decoder(new JacksonDecoder())
.target(WeedMasterClient.class, String.format("http://%s", leaderMasterUrl));
fetchMasters(leaderMaster.cluster());
masterHealthCheckThread.start();
volumeHealthCheckThread.start();
}
/**
* Shutdown weed manager.
*/
public void shutdown() {
masterHealthCheckThread.interrupt();
volumeHealthCheckThread.interrupt();
}
/**
* Get master server client.
*
* @return client.
*/
public WeedMasterClient getMasterClient() {
return this.leaderMaster;
}
/**
* Get volume server client.
*
* @return client.
*/
public WeedVolumeClient getVolumeClient(int volumeId, String collection) {
Set<String> volumeIds =
volumeCollectionIds.get(String.format("%d#%s", volumeId, collection != null ? collection : ""));
if (volumeIds == null || volumeIds.size() == 0)
volumeIds = fetchVolume(volumeId, collection);
final long millis = System.currentTimeMillis();
final int index = (int) (millis % volumeIds.size());
final String[] ids = new String[volumeIds.size()];
return volumeClients.get(volumeIds.toArray(ids)[index]);
}
/**
* Fetch volume server.
*
* @param volumeId Volume id.
* @param collection Collection.
* @return ids.
*/
private Set<String> fetchVolume(int volumeId, String collection) {
Locations locations = getMasterClient().lookup(volumeId, collection);
Set<String> ids = new HashSet<>();
locations.getLocations().forEach(location -> {
final String id = String.format("%s#%s", location.getUrl(), location.getUrl());
ids.add(id);
volumeClients.putIfAbsent(id, Feign.builder()
.client(new OkHttpClient())
.decoder(new JacksonDecoder())
.target(WeedVolumeClient.class, String.format("http://%s", location.getPublicUrl())));
});
return ids;
}
/**
* Master server host.
*
* @return host.
*/
public String getHost() {
return host;
}
/**
* Master server port.
*
* @return port.
*/
public int getPort() {
return port;
}
/**
* Assemble URL.
*
* @param host Host.
* @param port Port.
* @return URL.
*/
private String assembleUrl(String host, int port) {
return String.format("%s:%d", host, port);
}
/**
* Fetch master cluster information.
*
* @param cluster Master cluster information.
*/
private void fetchMasters(Cluster cluster) {
if (!leaderMasterUrl.equals(cluster.getLeader())) {
leaderMasterUrl = cluster.getLeader();
log.info("Weed leader master server is change to [{}]", leaderMasterUrl);
leaderMaster = Feign.builder()
.client(new OkHttpClient())
.decoder(new JacksonDecoder())
.target(WeedMasterClient.class, String.format("http://%s", leaderMaster));
}
// Cleanup peer master
Set<String> removeSet = peerMasters.keySet().stream().filter(
key -> !cluster.getPeers().contains(key) && !cluster.getLeader().equals(key))
.collect(Collectors.toSet());
peerMasters.remove(leaderMasterUrl);
removeSet.forEach(key -> peerMasters.remove(key));
cluster.getPeers().forEach(url -> {
if (!peerMasters.containsKey(url)) {
peerMasters.put(url,
Feign.builder()
.client(new OkHttpClient())
.decoder(new JacksonDecoder())
.target(WeedMasterClient.class, String.format("http://%s", url)));
}
});
}
/**
* Master server health check thread
*/
class MasterHealthCheckThread extends Thread {
@Override
public void run() {
log.info("Started weed leader master server health check");
//noinspection InfiniteLoopStatement
while (true) {
try {
Thread.sleep(3000);
} catch (InterruptedException e) {
log.info("Stop weed leader master server health check");
return;
}
try {
fetchMasters(leaderMaster.cluster());
} catch (Exception e) {
log.warn("Weed leader master server [{}] is down", leaderMasterUrl);
for (String url : peerMasters.keySet()) {
try {
fetchMasters(peerMasters.get(url).cluster());
} catch (Exception ignored) {
log.warn("Weed peer master server [{}] is down", url);
continue;
}
break;
}
}
}
}
}
/**
* Volume server health check thread
*/
class VolumeHealthCheckThread extends Thread {
@Override
public void run() {
log.info("Started weed leader master server health check");
//noinspection InfiniteLoopStatement
while (true) {
try {
Thread.sleep(3000);
} catch (InterruptedException e) {
log.info("Stop weed leader master server health check");
return;
}
try {
fetchMasters(leaderMaster.cluster());
} catch (Exception e) {
log.warn("Weed leader master server [{}] is down", leaderMasterUrl);
for (String url : peerMasters.keySet()) {
try {
fetchMasters(peerMasters.get(url).cluster());
} catch (Exception ignored) {
log.warn("Weed peer master server [{}] is down", url);
continue;
}
break;
}
}
}
}
}
}
