// Copyright 2017 JanusGraph Authors
//
// Licensed 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.janusgraph.diskstorage.keycolumnvalue.ttl;
import com.google.common.base.Preconditions;
import com.google.common.collect.Maps;
import org.janusgraph.diskstorage.BackendException;
import org.janusgraph.diskstorage.Entry;
import org.janusgraph.diskstorage.EntryMetaData;
import org.janusgraph.diskstorage.MetaAnnotatable;
import org.janusgraph.diskstorage.StaticBuffer;
import org.janusgraph.diskstorage.StoreMetaData;
import org.janusgraph.diskstorage.keycolumnvalue.KCVMutation;
import org.janusgraph.diskstorage.keycolumnvalue.KCVSManagerProxy;
import org.janusgraph.diskstorage.keycolumnvalue.KeyColumnValueStore;
import org.janusgraph.diskstorage.keycolumnvalue.KeyColumnValueStoreManager;
import org.janusgraph.diskstorage.keycolumnvalue.StandardStoreFeatures;
import org.janusgraph.diskstorage.keycolumnvalue.StoreFeatures;
import org.janusgraph.diskstorage.keycolumnvalue.StoreTransaction;
import java.util.Collection;
import java.util.Map;
/**
* Turns a store with fine-grained cell-level TTL support into a store
* with coarse-grained store-level (columnfamily-level) TTL support.
* Useful when running a KCVSLog atop Cassandra. Cassandra has
* cell-level TTL support, but KCVSLog just wants to write all of its
* data with a fixed, CF-wide TTL. This class stores a fixed TTL set
* during construction and applies it to every entry written through
* subsequent mutate/mutateMany calls.
*
* @author Matthias Broecheler (me@matthiasb.com)
*/
public class TTLKCVSManager extends KCVSManagerProxy {
private final StoreFeatures features;
private final Map<String, Integer> ttlEnabledStores = Maps.newConcurrentMap();
public TTLKCVSManager(KeyColumnValueStoreManager manager) {
super(manager);
Preconditions.checkArgument(manager.getFeatures().hasCellTTL());
Preconditions.checkArgument(!manager.getFeatures().hasStoreTTL(),
"Using TTLKCVSManager with %s is redundant: underlying implementation already supports store-level ttl",
manager);
this.features = new StandardStoreFeatures.Builder(manager.getFeatures()).storeTTL(true).build();
}
/**
* Returns true if the parameter supports at least one of the following:
*
* <ul>
* <li>cell-level TTL {@link StoreFeatures#hasCellTTL()}</li>
* <li>store-level TTL {@link StoreFeatures#hasStoreTTL()}</li>
* </ul>
*
* @param features an arbitrary {@code StoreFeatures} instance
* @return true if and only if at least one TTL mode is supported
*/
public static boolean supportsAnyTTL(StoreFeatures features) {
return features.hasCellTTL() || features.hasStoreTTL();
}
@Override
public StoreFeatures getFeatures() {
return features;
}
@Override
public KeyColumnValueStore openDatabase(String name) throws BackendException {
return openDatabase(name, StoreMetaData.EMPTY);
}
@Override
public KeyColumnValueStore openDatabase(String name, StoreMetaData.Container metaData) throws BackendException {
KeyColumnValueStore store = manager.openDatabase(name);
int storeTTL = -1;
if (metaData.contains(StoreMetaData.TTL)) {
storeTTL = (Integer) metaData.get(StoreMetaData.TTL);
}
Preconditions.checkArgument(storeTTL>0,"TTL must be positive: %s", storeTTL);
ttlEnabledStores.put(name, storeTTL);
return new TTLKCVS(store, storeTTL);
}
@Override
public void mutateMany(Map<String, Map<StaticBuffer, KCVMutation>> mutations, StoreTransaction txh) throws BackendException {
if (!manager.getFeatures().hasStoreTTL()) {
assert manager.getFeatures().hasCellTTL();
for (Map.Entry<String,Map<StaticBuffer, KCVMutation>> sentry : mutations.entrySet()) {
Integer ttl = ttlEnabledStores.get(sentry.getKey());
if (null != ttl && 0 < ttl) {
for (KCVMutation mut : sentry.getValue().values()) {
if (mut.hasAdditions()) applyTTL(mut.getAdditions(), ttl);
}
}
}
}
manager.mutateMany(mutations,txh);
}
public static void applyTTL(Collection<Entry> additions, int ttl) {
for (Entry entry : additions) {
assert entry instanceof MetaAnnotatable;
((MetaAnnotatable)entry).setMetaData(EntryMetaData.TTL, ttl);
}
}
}