josh-mckenzie commented on a change in pull request #1213: URL: https://github.com/apache/cassandra/pull/1213#discussion_r717009995
########## File path: src/java/org/apache/cassandra/schema/PartitionDenylist.java ########## @@ -0,0 +1,406 @@ +/* + * 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.cassandra.schema; + +import com.google.common.cache.CacheBuilder; +import com.google.common.cache.CacheLoader; +import com.google.common.cache.LoadingCache; +import com.google.common.collect.ImmutableSet; +import com.google.common.collect.ImmutableSortedSet; +import com.google.common.util.concurrent.ListenableFuture; +import com.google.common.util.concurrent.ListenableFutureTask; +import org.apache.cassandra.concurrent.ScheduledExecutors; +import org.apache.cassandra.config.DatabaseDescriptor; +import org.apache.cassandra.cql3.UntypedResultSet; +import org.apache.cassandra.db.PartitionPosition; +import org.apache.cassandra.dht.AbstractBounds; +import org.apache.cassandra.dht.Token; +import org.apache.cassandra.exceptions.RequestExecutionException; +import org.apache.cassandra.service.StorageService; +import org.apache.cassandra.service.reads.range.RangeCommands; +import org.apache.cassandra.utils.Hex; +import org.apache.cassandra.utils.Pair; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import java.nio.ByteBuffer; +import java.util.HashMap; +import java.util.HashSet; +import java.util.Iterator; +import java.util.Map; +import java.util.NavigableSet; +import java.util.Set; +import java.util.TreeSet; +import java.util.concurrent.Callable; +import java.util.concurrent.ExecutionException; +import java.util.concurrent.ExecutorService; +import java.util.concurrent.LinkedBlockingQueue; +import java.util.concurrent.ThreadPoolExecutor; +import java.util.concurrent.TimeUnit; + +import static org.apache.cassandra.cql3.QueryProcessor.process; + +/** + * PartitionDenylist uses the system_distributed.partition_denylist table to maintain a list of denylisted partition keys + * for each keyspace/table. + * + * Keys can be entered manually into the partition_denylist table or via the JMX operation StorageProxyMBean.denylistKey + * + * The denylist is stored as one CQL partition per table, and the denylisted keys are column names in that partition. The denylisted + * keys for each table are cached in memory, and reloaded from the partition_denylist table every 24 hours (default) or when the + * StorageProxyMBean.loadPartitionDenylist is called via JMX. + * + * Concurrency of the cache is provided by the concurrency semantics of the guava LoadingCache. All values (DenylistEntry) are + * immutable collections of keys/tokens which are replaced in whole when the cache refreshes from disk. + */ +public class PartitionDenylist +{ + private static final Logger logger = LoggerFactory.getLogger(PartitionDenylist.class); + public static final String PARTITION_DENYLIST_TABLE = "partition_denylist"; + + private final ExecutorService executor = new ThreadPoolExecutor(2, 2, Long.MAX_VALUE, TimeUnit.SECONDS, new LinkedBlockingQueue<>()); + private final LoadingCache<TableId, DenylistEntry> denylist = CacheBuilder.newBuilder() + .refreshAfterWrite(DatabaseDescriptor.getDenylistRefreshPeriodSeconds(), TimeUnit.SECONDS) + .build(new CacheLoader<TableId, DenylistEntry>() + { + @Override + public DenylistEntry load(final TableId tid) throws Exception + { + return readDenylist(tid); + } + + @Override + public ListenableFuture<DenylistEntry> reload(final TableId tid, final DenylistEntry oldValue) + { + ListenableFutureTask<DenylistEntry> task = ListenableFutureTask.create(new Callable<DenylistEntry>() + { + @Override + public DenylistEntry call() + { + final DenylistEntry newEntry = readDenylist(tid); + if (newEntry != null) + return newEntry; + if (oldValue != null) + return oldValue; + return new DenylistEntry(); + } + }); + executor.execute(task); + return task; + } + }); + + /** + * Denylist entry is never mutated once constructed, only replaced with a new entry when the cache is refreshed + */ + private static class DenylistEntry + { + public DenylistEntry() + { + keys = ImmutableSet.of(); + tokens = ImmutableSortedSet.of(); + } + + public DenylistEntry(final ImmutableSet<ByteBuffer> keys, final ImmutableSortedSet<Token> tokens) + { + this.keys = keys; + this.tokens = tokens; + } + + public final ImmutableSet<ByteBuffer> keys; + public final ImmutableSortedSet<Token> tokens; + } + + // synchronized on this + private int loadAttempts = 0; + private int loadSuccesses = 0; + + public synchronized int getLoadAttempts() + { + return loadAttempts; + } + public synchronized int getLoadSuccesses() + { + return loadSuccesses; + } + + /** + * Performs initial load of the partition denylist. Should be called at startup and only loads if the operation + * is expected to succeed. If it is not possible to load at call time, a timer is set to retry. + */ + public void initialLoad() + { + if (!DatabaseDescriptor.enablePartitionDenylist()) + return; + + synchronized (this) + { + loadAttempts++; + } + + // Check if there are sufficient nodes to attempt reading all the denylist partitions before issuing the query. + // The pre-check prevents definite range-slice unavailables being marked and triggering an alert. Nodes may still change + // state between the check and the query, but it should significantly reduce the alert volume. + String retryReason = "Insufficient nodes"; + try + { + if (readAllHasSufficientNodes() && load()) + { + return; + } + } + catch (Throwable tr) + { + logger.error("Failed to load partition denylist", tr); + retryReason = "Exception"; + } + + // This path will also be taken on other failures other than UnavailableException, + // but seems like a good idea to retry anyway. + int retryInSeconds = DatabaseDescriptor.getDenylistInitialLoadRetrySeconds(); + logger.info(retryReason + " while loading partition denylist cache. Scheduled retry in {} seconds.", + retryInSeconds); + ScheduledExecutors.optionalTasks.schedule(this::initialLoad, retryInSeconds, TimeUnit.SECONDS); + } + + private boolean readAllHasSufficientNodes() + { + return RangeCommands.sufficientLiveNodesForSelectStar(SystemDistributedKeyspace.PartitionDenylistTable, + DatabaseDescriptor.denylistConsistencyLevel()); + } + + public boolean load() + { + final long start = System.currentTimeMillis(); + final Map<TableId, DenylistEntry> allDenylists = readAll(); + if (allDenylists == null) + return false; + + // Cache iterators are weakly-consistent + for (final Iterator<TableId> it = denylist.asMap().keySet().iterator(); it.hasNext(); ) + { + final TableId tid = it.next(); + if (!allDenylists.containsKey(tid)) + allDenylists.put(tid, new DenylistEntry()); + } + denylist.putAll(allDenylists); + logger.info("Loaded partition denylist cache in {}ms", System.currentTimeMillis() - start); + + synchronized (this) + { + loadSuccesses++; + } + return true; + } + + public boolean denylist(final String keyspace, final String cf, final ByteBuffer key) Review comment: Nope; scratch that above idea. We partition on a composite of ks_name + cf_name and cluster on partition, so we wouldn't expect data in the underlying CQL table for a denylist entry to correspond to the node that actually owns the access to that data. -- 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] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
