| package net.onrc.onos.core.registry; |
| |
| import java.io.IOException; |
| import java.util.ArrayList; |
| import java.util.Collection; |
| import java.util.Collections; |
| import java.util.Comparator; |
| import java.util.HashMap; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.Random; |
| import java.util.concurrent.BlockingQueue; |
| import java.util.concurrent.ConcurrentHashMap; |
| import java.util.concurrent.ExecutorService; |
| import java.util.concurrent.Executors; |
| import java.util.concurrent.LinkedBlockingQueue; |
| |
| import net.floodlightcontroller.core.IFloodlightProviderService; |
| import net.floodlightcontroller.core.module.FloodlightModuleContext; |
| import net.floodlightcontroller.core.module.FloodlightModuleException; |
| import net.floodlightcontroller.core.module.IFloodlightModule; |
| import net.floodlightcontroller.core.module.IFloodlightService; |
| import net.floodlightcontroller.restserver.IRestApiService; |
| import net.onrc.onos.core.registry.web.RegistryWebRoutable; |
| |
| import org.apache.curator.RetryPolicy; |
| import org.apache.curator.framework.CuratorFramework; |
| import org.apache.curator.framework.CuratorFrameworkFactory; |
| import org.apache.curator.framework.recipes.atomic.AtomicValue; |
| import org.apache.curator.framework.recipes.atomic.DistributedAtomicLong; |
| import org.apache.curator.framework.recipes.cache.ChildData; |
| import org.apache.curator.framework.recipes.cache.PathChildrenCache; |
| import org.apache.curator.framework.recipes.cache.PathChildrenCache.StartMode; |
| import org.apache.curator.framework.recipes.cache.PathChildrenCacheEvent; |
| import org.apache.curator.framework.recipes.cache.PathChildrenCacheListener; |
| import org.apache.curator.framework.recipes.leader.LeaderLatch; |
| import org.apache.curator.framework.recipes.leader.LeaderLatchListener; |
| import org.apache.curator.framework.recipes.leader.Participant; |
| import org.apache.curator.retry.ExponentialBackoffRetry; |
| import org.apache.curator.retry.RetryOneTime; |
| import org.apache.curator.x.discovery.ServiceCache; |
| import org.apache.curator.x.discovery.ServiceDiscovery; |
| import org.apache.curator.x.discovery.ServiceDiscoveryBuilder; |
| import org.apache.curator.x.discovery.ServiceInstance; |
| import org.openflow.util.HexString; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import com.google.common.base.Charsets; |
| |
| /** |
| * A registry service that uses Zookeeper. All data is stored in Zookeeper, |
| * so this can be used as a global registry in a multi-node ONOS cluster. |
| * |
| * @author jono |
| */ |
| public class ZookeeperRegistry implements IFloodlightModule, IControllerRegistryService { |
| |
| private static final Logger log = LoggerFactory.getLogger(ZookeeperRegistry.class); |
| protected String controllerId = null; |
| |
| protected IRestApiService restApi; |
| |
| //This is the default, it's overwritten by the connectionString configuration parameter |
| protected String connectionString = "localhost:2181"; |
| |
| private final String namespace = "onos"; |
| private final String switchLatchesPath = "/switches"; |
| private static final String CLUSTER_LEADER_PATH = "/cluster/leader"; |
| |
| private static final String SERVICES_PATH = "/"; //i.e. the root of our namespace |
| private static final String CONTROLLER_SERVICE_NAME = "controllers"; |
| |
| protected CuratorFramework client; |
| |
| protected PathChildrenCache switchCache; |
| |
| protected ConcurrentHashMap<String, SwitchLeadershipData> switches; |
| protected Map<String, PathChildrenCache> switchPathCaches; |
| |
| protected LeaderLatch clusterLeaderLatch; |
| protected ClusterLeaderListener clusterLeaderListener; |
| private static final long CLUSTER_LEADER_ELECTION_RETRY_MS = 100; |
| |
| private static final String ID_COUNTER_PATH = "/flowidcounter"; |
| private static final Long ID_BLOCK_SIZE = 0x100000000L; |
| protected DistributedAtomicLong distributedIdCounter; |
| |
| //Zookeeper performance-related configuration |
| protected static final int SESSION_TIMEOUT = 5000; |
| protected static final int CONNECTION_TIMEOUT = 7000; |
| |
| // |
| // Unique ID generation state |
| // TODO: The implementation must be updated to use the Zookeeper |
| // instead of a ramdon generator. |
| // |
| private static Random randomGenerator = new Random(); |
| private static int nextUniqueIdPrefix = 0; |
| private static int nextUniqueIdSuffix = 0; |
| |
| private final BlockingQueue<SwitchLeaderEvent> switchLeadershipEvents = |
| new LinkedBlockingQueue<SwitchLeaderEvent>(); |
| |
| private ExecutorService eventThreadExecutorService; |
| |
| private static class SwitchLeaderEvent { |
| public final long dpid; |
| public final boolean isLeader; |
| |
| public SwitchLeaderEvent(long dpid, boolean isLeader) { |
| this.dpid = dpid; |
| this.isLeader = isLeader; |
| } |
| } |
| |
| /* |
| * Dispatcher thread for leadership change events coming from Curator. |
| */ |
| private void dispatchEvents() { |
| while (!Thread.currentThread().isInterrupted()) { |
| try { |
| SwitchLeaderEvent event = switchLeadershipEvents.take(); |
| SwitchLeadershipData swData = switches.get(HexString.toHexString(event.dpid)); |
| if (swData == null) { |
| log.debug("Leadership data {} not found", event.dpid); |
| continue; |
| } |
| |
| swData.getCallback().controlChanged(event.dpid, event.isLeader); |
| } catch (InterruptedException e) { |
| Thread.currentThread().interrupt(); |
| break; |
| } catch (Exception e) { |
| log.error("Exception in registry event thread", e); |
| } |
| } |
| } |
| |
| protected class SwitchLeaderListener implements LeaderLatchListener { |
| String dpid; |
| LeaderLatch latch; |
| |
| public SwitchLeaderListener(String dpid, LeaderLatch latch) { |
| this.dpid = dpid; |
| this.latch = latch; |
| } |
| |
| @Override |
| public void isLeader() { |
| log.debug("Became leader for {}", dpid); |
| |
| switchLeadershipEvents.offer(new SwitchLeaderEvent(HexString.toLong(dpid), true)); |
| } |
| |
| @Override |
| public void notLeader() { |
| log.debug("Lost leadership for {}", dpid); |
| |
| switchLeadershipEvents.offer(new SwitchLeaderEvent(HexString.toLong(dpid), false)); |
| } |
| } |
| |
| protected class SwitchPathCacheListener implements PathChildrenCacheListener { |
| @Override |
| public void childEvent(CuratorFramework client, |
| PathChildrenCacheEvent event) throws Exception { |
| |
| String strSwitch = null; |
| if (event.getData() != null) { |
| String[] splitted = event.getData().getPath().split("/"); |
| strSwitch = splitted[splitted.length - 1]; |
| } |
| |
| switch (event.getType()) { |
| case CHILD_ADDED: |
| case CHILD_UPDATED: |
| //Check we have a PathChildrenCache for this child, add one if not |
| synchronized (switchPathCaches) { |
| if (switchPathCaches.get(strSwitch) == null) { |
| PathChildrenCache pc = new PathChildrenCache(client, |
| event.getData().getPath(), true); |
| pc.start(StartMode.NORMAL); |
| switchPathCaches.put(strSwitch, pc); |
| } |
| } |
| break; |
| case CHILD_REMOVED: |
| //Remove our PathChildrenCache for this child |
| PathChildrenCache pc = null; |
| synchronized (switchPathCaches) { |
| pc = switchPathCaches.remove(strSwitch); |
| } |
| if (pc != null) { |
| pc.close(); |
| } |
| break; |
| default: |
| //All other switchLeadershipEvents are connection status switchLeadershipEvents. We don't need to |
| //do anything as the path cache handles these on its own. |
| break; |
| } |
| |
| } |
| } |
| |
| protected static class ClusterLeaderListener implements LeaderLatchListener { |
| LeaderLatch latch; |
| |
| public ClusterLeaderListener(LeaderLatch latch) { |
| this.latch = latch; |
| } |
| |
| // |
| // NOTE: If we need to support callbacks when the |
| // leadership changes, those should be called here. |
| // |
| |
| @Override |
| public void isLeader() { |
| log.debug("Cluster leadership aquired"); |
| } |
| |
| @Override |
| public void notLeader() { |
| log.debug("Cluster leadership lost"); |
| } |
| } |
| |
| /** |
| * Listens for changes to the switch znodes in Zookeeper. This maintains |
| * the second level of PathChildrenCaches that hold the controllers |
| * contending for each switch - there's one for each switch. |
| */ |
| PathChildrenCacheListener switchPathCacheListener = new SwitchPathCacheListener(); |
| protected ServiceDiscovery<ControllerService> serviceDiscovery; |
| protected ServiceCache<ControllerService> serviceCache; |
| |
| |
| @Override |
| public void requestControl(long dpid, ControlChangeCallback cb) throws RegistryException { |
| log.info("Requesting control for {}", HexString.toHexString(dpid)); |
| |
| if (controllerId == null) { |
| throw new RuntimeException("Must register a controller before calling requestControl"); |
| } |
| |
| String dpidStr = HexString.toHexString(dpid); |
| String latchPath = switchLatchesPath + "/" + dpidStr; |
| |
| if (switches.get(dpidStr) != null) { |
| log.debug("Already contesting {}, returning", HexString.toHexString(dpid)); |
| throw new RegistryException("Already contesting control for " + dpidStr); |
| } |
| |
| LeaderLatch latch = new LeaderLatch(client, latchPath, controllerId); |
| SwitchLeaderListener listener = new SwitchLeaderListener(dpidStr, latch); |
| latch.addListener(listener); |
| |
| |
| SwitchLeadershipData swData = new SwitchLeadershipData(latch, cb, listener); |
| SwitchLeadershipData oldData = switches.putIfAbsent(dpidStr, swData); |
| |
| if (oldData != null) { |
| //There was already data for that key in the map |
| //i.e. someone else got here first so we can't succeed |
| log.debug("Already requested control for {}", dpidStr); |
| throw new RegistryException("Already requested control for " + dpidStr); |
| } |
| |
| //Now that we know we were able to add our latch to the collection, |
| //we can start the leader election in Zookeeper. However I don't know |
| //how to handle if the start fails - the latch is already in our |
| //switches list. |
| //TODO seems like there's a Curator bug when latch.start is called when |
| //there's no Zookeeper connection which causes two znodes to be put in |
| //Zookeeper at the latch path when we reconnect to Zookeeper. |
| try { |
| latch.start(); |
| } catch (Exception e) { |
| log.warn("Error starting leader latch: {}", e.getMessage()); |
| throw new RegistryException("Error starting leader latch for " + dpidStr, e); |
| } |
| |
| } |
| |
| @Override |
| public void releaseControl(long dpid) { |
| log.info("Releasing control for {}", HexString.toHexString(dpid)); |
| |
| String dpidStr = HexString.toHexString(dpid); |
| |
| SwitchLeadershipData swData = switches.remove(dpidStr); |
| |
| if (swData == null) { |
| log.debug("Trying to release control of a switch we are not contesting"); |
| return; |
| } |
| |
| LeaderLatch latch = swData.getLatch(); |
| |
| latch.removeListener(swData.getListener()); |
| |
| try { |
| latch.close(); |
| } catch (IOException e) { |
| //I think it's OK not to do anything here. Either the node got |
| //deleted correctly, or the connection went down and the node got deleted. |
| log.debug("releaseControl: caught IOException {}", dpidStr); |
| } |
| } |
| |
| @Override |
| public boolean hasControl(long dpid) { |
| String dpidStr = HexString.toHexString(dpid); |
| |
| SwitchLeadershipData swData = switches.get(dpidStr); |
| |
| if (swData == null) { |
| log.warn("No leader latch for dpid {}", dpidStr); |
| return false; |
| } |
| |
| return swData.getLatch().hasLeadership(); |
| } |
| |
| @Override |
| public boolean isClusterLeader() { |
| return clusterLeaderLatch.hasLeadership(); |
| } |
| |
| @Override |
| public String getControllerId() { |
| return controllerId; |
| } |
| |
| @Override |
| public Collection<String> getAllControllers() throws RegistryException { |
| log.debug("Getting all controllers"); |
| |
| List<String> controllers = new ArrayList<String>(); |
| for (ServiceInstance<ControllerService> instance : serviceCache.getInstances()) { |
| String id = instance.getPayload().getControllerId(); |
| if (!controllers.contains(id)) { |
| controllers.add(id); |
| } |
| } |
| |
| return controllers; |
| } |
| |
| @Override |
| public void registerController(String id) throws RegistryException { |
| if (controllerId != null) { |
| throw new RegistryException( |
| "Controller already registered with id " + controllerId); |
| } |
| |
| controllerId = id; |
| |
| try { |
| ServiceInstance<ControllerService> thisInstance = ServiceInstance.<ControllerService>builder() |
| .name(CONTROLLER_SERVICE_NAME) |
| .payload(new ControllerService(controllerId)) |
| //.port((int)(65535 * Math.random())) // in a real application, you'd use a common port |
| //.uriSpec(uriSpec) |
| .build(); |
| |
| serviceDiscovery.registerService(thisInstance); |
| } catch (Exception e) { |
| // TODO Auto-generated catch block |
| e.printStackTrace(); |
| } |
| |
| } |
| |
| @Override |
| public String getControllerForSwitch(long dpid) throws RegistryException { |
| String dpidStr = HexString.toHexString(dpid); |
| |
| PathChildrenCache switchCache = switchPathCaches.get(dpidStr); |
| |
| if (switchCache == null) { |
| log.warn("Tried to get controller for non-existent switch"); |
| return null; |
| } |
| |
| try { |
| //We've seen issues with these caches get stuck out of date, so we'll have to |
| //force them to refresh before each read. This slows down the method as it |
| //blocks on a Zookeeper query, however at the moment only the cleanup thread |
| //uses this and that isn't particularly time-sensitive. |
| switchCache.rebuild(); |
| } catch (Exception e) { |
| // TODO Auto-generated catch block |
| e.printStackTrace(); |
| } |
| |
| List<ChildData> sortedData = new ArrayList<ChildData>(switchCache.getCurrentData()); |
| |
| Collections.sort( |
| sortedData, |
| new Comparator<ChildData>() { |
| private String getSequenceNumber(String path) { |
| return path.substring(path.lastIndexOf('-') + 1); |
| } |
| |
| @Override |
| public int compare(ChildData lhs, ChildData rhs) { |
| return getSequenceNumber(lhs.getPath()). |
| compareTo(getSequenceNumber(rhs.getPath())); |
| } |
| } |
| ); |
| |
| if (sortedData.size() == 0) { |
| return null; |
| } |
| |
| return new String(sortedData.get(0).getData(), Charsets.UTF_8); |
| } |
| |
| @Override |
| public Collection<Long> getSwitchesControlledByController(String controllerId) { |
| //TODO remove this if not needed |
| throw new RuntimeException("Not yet implemented"); |
| } |
| |
| |
| //TODO what should happen when there's no ZK connection? Currently we just return |
| //the cache but this may lead to false impressions - i.e. we don't actually know |
| //what's in ZK so we shouldn't say we do |
| @Override |
| public Map<String, List<ControllerRegistryEntry>> getAllSwitches() { |
| Map<String, List<ControllerRegistryEntry>> data = |
| new HashMap<String, List<ControllerRegistryEntry>>(); |
| |
| for (Map.Entry<String, PathChildrenCache> entry : switchPathCaches.entrySet()) { |
| List<ControllerRegistryEntry> contendingControllers = |
| new ArrayList<ControllerRegistryEntry>(); |
| |
| if (entry.getValue().getCurrentData().size() < 1) { |
| //TODO prevent even having the PathChildrenCache in this case |
| //log.info("Switch entry with no leader elections: {}", entry.getKey()); |
| continue; |
| } |
| |
| for (ChildData d : entry.getValue().getCurrentData()) { |
| |
| String controllerId = new String(d.getData(), Charsets.UTF_8); |
| |
| String[] splitted = d.getPath().split("-"); |
| int sequenceNumber = Integer.parseInt(splitted[splitted.length - 1]); |
| |
| contendingControllers.add(new ControllerRegistryEntry(controllerId, sequenceNumber)); |
| } |
| |
| Collections.sort(contendingControllers); |
| data.put(entry.getKey(), contendingControllers); |
| } |
| return data; |
| } |
| |
| public IdBlock allocateUniqueIdBlock(long range) { |
| try { |
| AtomicValue<Long> result = null; |
| do { |
| result = distributedIdCounter.add(range); |
| } while (result == null || !result.succeeded()); |
| |
| return new IdBlock(result.preValue(), result.postValue() - 1, range); |
| } catch (Exception e) { |
| log.error("Error allocating ID block"); |
| } |
| return null; |
| } |
| |
| /** |
| * Returns a block of IDs which are unique and unused. |
| * Range of IDs is fixed size and is assigned incrementally as this method called. |
| * Since the range of IDs is managed by Zookeeper in distributed way, this method may block when |
| * requests come up simultaneously. |
| */ |
| @Override |
| public IdBlock allocateUniqueIdBlock() { |
| return allocateUniqueIdBlock(ID_BLOCK_SIZE); |
| } |
| |
| /** |
| * Get a globally unique ID. |
| * |
| * @return a globally unique ID. |
| */ |
| @Override |
| public synchronized long getNextUniqueId() { |
| // |
| // Generate the next Unique ID. |
| // |
| // TODO: For now, the higher 32 bits are random, and |
| // the lower 32 bits are sequential. |
| // The implementation must be updated to use the Zookeeper |
| // to allocate the higher 32 bits (globally unique). |
| // |
| if ((nextUniqueIdSuffix & 0xffffffffL) == 0xffffffffL) { |
| nextUniqueIdPrefix = randomGenerator.nextInt(); |
| nextUniqueIdSuffix = 0; |
| } else { |
| nextUniqueIdSuffix++; |
| } |
| long result = (long) nextUniqueIdPrefix << 32; |
| result = result | (0xffffffffL & nextUniqueIdSuffix); |
| return result; |
| } |
| |
| /* |
| * IFloodlightModule |
| */ |
| |
| @Override |
| public Collection<Class<? extends IFloodlightService>> getModuleServices() { |
| Collection<Class<? extends IFloodlightService>> l = |
| new ArrayList<Class<? extends IFloodlightService>>(); |
| l.add(IControllerRegistryService.class); |
| return l; |
| } |
| |
| @Override |
| public Map<Class<? extends IFloodlightService>, IFloodlightService> getServiceImpls() { |
| Map<Class<? extends IFloodlightService>, IFloodlightService> m = |
| new HashMap<Class<? extends IFloodlightService>, IFloodlightService>(); |
| m.put(IControllerRegistryService.class, this); |
| return m; |
| } |
| |
| @Override |
| public Collection<Class<? extends IFloodlightService>> getModuleDependencies() { |
| Collection<Class<? extends IFloodlightService>> l = |
| new ArrayList<Class<? extends IFloodlightService>>(); |
| l.add(IFloodlightProviderService.class); |
| l.add(IRestApiService.class); |
| return l; |
| } |
| |
| //TODO currently blocks startup when it can't get a Zookeeper connection. |
| //Do we support starting up with no Zookeeper connection? |
| @Override |
| public void init(FloodlightModuleContext context) throws FloodlightModuleException { |
| log.info("Initialising the Zookeeper Registry - Zookeeper connection required"); |
| |
| //Read the Zookeeper connection string from the config |
| Map<String, String> configParams = context.getConfigParams(this); |
| String connectionString = configParams.get("connectionString"); |
| if (connectionString != null) { |
| this.connectionString = connectionString; |
| } |
| log.info("Setting Zookeeper connection string to {}", this.connectionString); |
| |
| // |
| // Initialize the Unique ID generator |
| // TODO: This must be replaced by Zookeeper-based allocation |
| // |
| nextUniqueIdPrefix = randomGenerator.nextInt(); |
| |
| restApi = context.getServiceImpl(IRestApiService.class); |
| |
| switches = new ConcurrentHashMap<String, SwitchLeadershipData>(); |
| //switchPathCaches = new HashMap<String, PathChildrenCache>(); |
| switchPathCaches = new ConcurrentHashMap<String, PathChildrenCache>(); |
| |
| RetryPolicy retryPolicy = new ExponentialBackoffRetry(1000, 3); |
| client = CuratorFrameworkFactory.newClient(this.connectionString, |
| SESSION_TIMEOUT, CONNECTION_TIMEOUT, retryPolicy); |
| |
| client.start(); |
| client = client.usingNamespace(namespace); |
| |
| distributedIdCounter = new DistributedAtomicLong( |
| client, |
| ID_COUNTER_PATH, |
| new RetryOneTime(100)); |
| |
| switchCache = new PathChildrenCache(client, switchLatchesPath, true); |
| switchCache.getListenable().addListener(switchPathCacheListener); |
| |
| //Build the service discovery object |
| serviceDiscovery = ServiceDiscoveryBuilder.builder(ControllerService.class) |
| .client(client).basePath(SERVICES_PATH).build(); |
| |
| //We read the list of services very frequently (GUI periodically queries them) |
| //so we'll cache them to cut down on Zookeeper queries. |
| serviceCache = serviceDiscovery.serviceCacheBuilder() |
| .name(CONTROLLER_SERVICE_NAME).build(); |
| |
| |
| try { |
| serviceDiscovery.start(); |
| serviceCache.start(); |
| |
| //Don't prime the cache, we want a notification for each child node in the path |
| switchCache.start(StartMode.NORMAL); |
| } catch (Exception e) { |
| throw new FloodlightModuleException("Error initialising ZookeeperRegistry: " |
| + e.getMessage()); |
| } |
| |
| eventThreadExecutorService = Executors.newSingleThreadExecutor(); |
| eventThreadExecutorService.execute( |
| new Runnable() { |
| @Override |
| public void run() { |
| dispatchEvents(); |
| } |
| }); |
| } |
| |
| @Override |
| public void startUp(FloodlightModuleContext context) { |
| // |
| // Cluster Leader election setup. |
| // NOTE: We have to do it here, because during the init stage |
| // we don't know the Controller ID. |
| // |
| if (controllerId == null) { |
| log.error("Error on startup: unknown ControllerId"); |
| } |
| clusterLeaderLatch = new LeaderLatch(client, |
| CLUSTER_LEADER_PATH, |
| controllerId); |
| clusterLeaderListener = new ClusterLeaderListener(clusterLeaderLatch); |
| clusterLeaderLatch.addListener(clusterLeaderListener); |
| try { |
| clusterLeaderLatch.start(); |
| } catch (Exception e) { |
| log.error("Error on startup starting the cluster leader election: {}", e.getMessage()); |
| } |
| |
| // Keep trying until there is a cluster leader |
| do { |
| try { |
| Participant leader = clusterLeaderLatch.getLeader(); |
| if (!leader.getId().isEmpty()) { |
| break; |
| } |
| Thread.sleep(CLUSTER_LEADER_ELECTION_RETRY_MS); |
| } catch (Exception e) { |
| log.error("Error on startup waiting for cluster leader election: {}", e.getMessage()); |
| } |
| } while (true); |
| |
| restApi.addRestletRoutable(new RegistryWebRoutable()); |
| } |
| } |