org.apache.kafka.streams.state.internals.PrefixedSessionKeySchemas Maven / Gradle / Ivy
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* 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,
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* See the License for the specific language governing permissions and
* limitations under the License.
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package org.apache.kafka.streams.state.internals;
import org.apache.kafka.common.serialization.Deserializer;
import org.apache.kafka.common.serialization.Serializer;
import org.apache.kafka.common.utils.Bytes;
import org.apache.kafka.streams.kstream.Window;
import org.apache.kafka.streams.kstream.Windowed;
import org.apache.kafka.streams.kstream.internals.SessionWindow;
import org.apache.kafka.streams.state.internals.SegmentedBytesStore.KeySchema;
import java.nio.ByteBuffer;
import java.util.List;
import static org.apache.kafka.streams.state.StateSerdes.TIMESTAMP_SIZE;
public class PrefixedSessionKeySchemas {
private static final int PREFIX_SIZE = 1;
private static final byte TIME_FIRST_PREFIX = 0;
private static final byte KEY_FIRST_PREFIX = 1;
private static byte extractPrefix(final byte[] binaryBytes) {
return binaryBytes[0];
}
public static class TimeFirstSessionKeySchema implements KeySchema {
@Override
public Bytes upperRange(final Bytes key, final long to) {
if (key == null) {
// Put next prefix instead of null so that we can start from right prefix
// when scanning backwards
final byte nextPrefix = TIME_FIRST_PREFIX + 1;
return Bytes.wrap(ByteBuffer.allocate(PREFIX_SIZE).put(nextPrefix).array());
}
return Bytes.wrap(ByteBuffer.allocate(PREFIX_SIZE + 2 * TIMESTAMP_SIZE + key.get().length)
.put(TIME_FIRST_PREFIX)
// the end timestamp can be as large as possible as long as it's larger than start time
.putLong(Long.MAX_VALUE)
// this is the start timestamp
.putLong(to)
.put(key.get())
.array());
}
@Override
public Bytes lowerRange(final Bytes key, final long from) {
if (key == null) {
return Bytes.wrap(ByteBuffer.allocate(PREFIX_SIZE + TIMESTAMP_SIZE)
.put(TIME_FIRST_PREFIX)
.putLong(from)
.array());
}
return Bytes.wrap(ByteBuffer.allocate(PREFIX_SIZE + 2 * TIMESTAMP_SIZE + key.get().length)
.put(TIME_FIRST_PREFIX)
.putLong(from)
.putLong(0L)
.put(key.get())
.array());
}
/**
* @param key the key in the range
* @param to the latest start time
*/
@Override
public Bytes upperRangeFixedSize(final Bytes key, final long to) {
return toBinary(key, to, Long.MAX_VALUE);
}
/**
* @param key the key in the range
* @param from the earliest end timestamp in the range
*/
@Override
public Bytes lowerRangeFixedSize(final Bytes key, final long from) {
return toBinary(key, 0, Math.max(0, from));
}
@Override
public long segmentTimestamp(final Bytes key) {
return extractEndTimestamp(key.get());
}
@Override
public HasNextCondition hasNextCondition(final Bytes binaryKeyFrom,
final Bytes binaryKeyTo,
final long earliestWindowEndTime,
final long latestWindowStartTime,
final boolean forward) {
return iterator -> {
while (iterator.hasNext()) {
final Bytes bytes = iterator.peekNextKey();
final byte prefix = extractPrefix(bytes.get());
if (prefix != TIME_FIRST_PREFIX) {
return false;
}
final Windowed windowedKey = from(bytes);
final long endTime = windowedKey.window().end();
final long startTime = windowedKey.window().start();
// We can return false directly here since keys are sorted by end time and if
// we get time smaller than `from`, there won't be time within range.
if (!forward && endTime < earliestWindowEndTime) {
return false;
}
if ((binaryKeyFrom == null || windowedKey.key().compareTo(binaryKeyFrom) >= 0)
&& (binaryKeyTo == null || windowedKey.key().compareTo(binaryKeyTo) <= 0)
&& endTime >= earliestWindowEndTime && startTime <= latestWindowStartTime) {
return true;
}
iterator.next();
}
return false;
};
}
@Override
public List segmentsToSearch(final Segments segments,
final long earliestWindowEndTime,
final long latestWindowStartTime,
final boolean forward) {
return segments.segments(earliestWindowEndTime, Long.MAX_VALUE, forward);
}
static long extractStartTimestamp(final byte[] binaryKey) {
return ByteBuffer.wrap(binaryKey).getLong(PREFIX_SIZE + TIMESTAMP_SIZE);
}
static long extractEndTimestamp(final byte[] binaryKey) {
return ByteBuffer.wrap(binaryKey).getLong(PREFIX_SIZE);
}
private static K extractKey(final byte[] binaryKey,
final Deserializer deserializer,
final String topic) {
return deserializer.deserialize(topic, extractKeyBytes(binaryKey));
}
static byte[] extractKeyBytes(final byte[] binaryKey) {
final byte[] bytes = new byte[binaryKey.length - 2 * TIMESTAMP_SIZE - PREFIX_SIZE];
System.arraycopy(binaryKey, PREFIX_SIZE + 2 * TIMESTAMP_SIZE, bytes, 0, bytes.length);
return bytes;
}
static Window extractWindow(final byte[] binaryKey) {
final ByteBuffer buffer = ByteBuffer.wrap(binaryKey);
final long start = buffer.getLong(PREFIX_SIZE + TIMESTAMP_SIZE);
final long end = buffer.getLong(PREFIX_SIZE);
return new SessionWindow(start, end);
}
public static Windowed from(final Bytes bytesKey) {
final byte[] binaryKey = bytesKey.get();
final Window window = extractWindow(binaryKey);
return new Windowed<>(Bytes.wrap(extractKeyBytes(binaryKey)), window);
}
public static Windowed from(final byte[] binaryKey,
final Deserializer keyDeserializer,
final String topic) {
final K key = extractKey(binaryKey, keyDeserializer, topic);
final Window window = extractWindow(binaryKey);
return new Windowed<>(key, window);
}
public static byte[] toBinary(final Windowed sessionKey,
final Serializer serializer,
final String topic) {
final byte[] bytes = serializer.serialize(topic, sessionKey.key());
return toBinary(Bytes.wrap(bytes), sessionKey.window().start(), sessionKey.window().end()).get();
}
public static Bytes toBinary(final Windowed sessionKey) {
return toBinary(sessionKey.key(), sessionKey.window().start(), sessionKey.window().end());
}
// for time prefixed schema, like the session key schema we need to put time stamps first, then the key
// and hence we need to override the write binary function with the write reordering
public static void writeBinary(final ByteBuffer buf,
final Bytes key,
final long startTime,
final long endTime) {
buf.putLong(endTime);
buf.putLong(startTime);
if (key != null) {
buf.put(key.get());
}
}
public static Bytes toBinary(final Bytes key,
final long startTime,
final long endTime) {
final ByteBuffer buf = ByteBuffer.allocate(PREFIX_SIZE + SessionKeySchema.keyByteLength(key));
buf.put(TIME_FIRST_PREFIX);
writeBinary(buf, key, startTime, endTime);
return Bytes.wrap(buf.array());
}
public static byte[] extractWindowBytesFromNonPrefixSessionKey(final byte[] binaryKey) {
final ByteBuffer buffer = ByteBuffer.allocate(PREFIX_SIZE + binaryKey.length).put(TIME_FIRST_PREFIX);
// Put timestamp
buffer.put(binaryKey, binaryKey.length - 2 * TIMESTAMP_SIZE, 2 * TIMESTAMP_SIZE);
buffer.put(binaryKey, 0, binaryKey.length - 2 * TIMESTAMP_SIZE);
return buffer.array();
}
}
public static class KeyFirstSessionKeySchema implements KeySchema {
@Override
public Bytes upperRange(final Bytes key, final long to) {
final Bytes noPrefixBytes = new SessionKeySchema().upperRange(key, to);
return wrapPrefix(noPrefixBytes, true);
}
@Override
public Bytes lowerRange(final Bytes key, final long from) {
final Bytes noPrefixBytes = new SessionKeySchema().lowerRange(key, from);
// Wrap at least prefix even key is null
return wrapPrefix(noPrefixBytes, false);
}
@Override
public Bytes upperRangeFixedSize(final Bytes key, final long to) {
final ByteBuffer buffer = ByteBuffer.allocate(PREFIX_SIZE + SessionKeySchema.keyByteLength(key));
buffer.put(KEY_FIRST_PREFIX);
SessionKeySchema.writeBinary(buffer, SessionKeySchema.upperRangeFixedWindow(key, to));
return Bytes.wrap(buffer.array());
}
@Override
public Bytes lowerRangeFixedSize(final Bytes key, final long from) {
final ByteBuffer buffer = ByteBuffer.allocate(PREFIX_SIZE + SessionKeySchema.keyByteLength(key));
buffer.put(KEY_FIRST_PREFIX);
SessionKeySchema.writeBinary(buffer, SessionKeySchema.lowerRangeFixedWindow(key, from));
return Bytes.wrap(buffer.array());
}
@Override
public long segmentTimestamp(final Bytes key) {
return extractEndTimestamp(key.get());
}
@Override
public HasNextCondition hasNextCondition(final Bytes binaryKeyFrom,
final Bytes binaryKeyTo,
final long from,
final long to,
final boolean forward) {
return iterator -> {
while (iterator.hasNext()) {
final Bytes bytes = iterator.peekNextKey();
final byte prefix = extractPrefix(bytes.get());
if (prefix != KEY_FIRST_PREFIX) {
return false;
}
final Windowed windowedKey = from(bytes);
final long endTime = windowedKey.window().end();
final long startTime = windowedKey.window().start();
if ((binaryKeyFrom == null || windowedKey.key().compareTo(binaryKeyFrom) >= 0)
&& (binaryKeyTo == null || windowedKey.key().compareTo(binaryKeyTo) <= 0)
&& endTime >= from
&& startTime <= to) {
return true;
}
iterator.next();
}
return false;
};
}
@Override
public List segmentsToSearch(final Segments segments,
final long from,
final long to,
final boolean forward) {
return segments.segments(from, Long.MAX_VALUE, forward);
}
static Window extractWindow(final byte[] binaryKey) {
final ByteBuffer buffer = ByteBuffer.wrap(binaryKey);
final long start = buffer.getLong(binaryKey.length - TIMESTAMP_SIZE);
final long end = buffer.getLong(binaryKey.length - 2 * TIMESTAMP_SIZE);
return new SessionWindow(start, end);
}
static byte[] extractKeyBytes(final byte[] binaryKey) {
final byte[] bytes = new byte[binaryKey.length - 2 * TIMESTAMP_SIZE - PREFIX_SIZE];
System.arraycopy(binaryKey, PREFIX_SIZE, bytes, 0, bytes.length);
return bytes;
}
public static Windowed from(final Bytes bytesKey) {
final byte[] binaryKey = bytesKey.get();
final Window window = extractWindow(binaryKey);
return new Windowed<>(Bytes.wrap(extractKeyBytes(binaryKey)), window);
}
private static K extractKey(final byte[] binaryKey,
final Deserializer deserializer,
final String topic) {
return deserializer.deserialize(topic, extractKeyBytes(binaryKey));
}
public static Windowed from(final byte[] binaryKey,
final Deserializer keyDeserializer,
final String topic) {
final K key = extractKey(binaryKey, keyDeserializer, topic);
final Window window = extractWindow(binaryKey);
return new Windowed<>(key, window);
}
static long extractStartTimestamp(final byte[] binaryKey) {
return ByteBuffer.wrap(binaryKey).getLong(binaryKey.length - TIMESTAMP_SIZE);
}
static long extractEndTimestamp(final byte[] binaryKey) {
return ByteBuffer.wrap(binaryKey).getLong(binaryKey.length - 2 * TIMESTAMP_SIZE);
}
public static Bytes toBinary(final Windowed sessionKey) {
return toBinary(sessionKey.key(), sessionKey.window().start(), sessionKey.window().end());
}
public static byte[] toBinary(final Windowed sessionKey,
final Serializer serializer,
final String topic) {
final byte[] bytes = serializer.serialize(topic, sessionKey.key());
return toBinary(Bytes.wrap(bytes), sessionKey.window().start(), sessionKey.window().end()).get();
}
public static Bytes toBinary(final Bytes key,
final long startTime,
final long endTime) {
final ByteBuffer buf = ByteBuffer.allocate(PREFIX_SIZE + SessionKeySchema.keyByteLength(key));
buf.put(KEY_FIRST_PREFIX);
SessionKeySchema.writeBinary(buf, key, startTime, endTime);
return Bytes.wrap(buf.array());
}
private static Bytes wrapPrefix(final Bytes noPrefixKey, final boolean upperRange) {
// Need to scan from prefix even key is null
if (noPrefixKey == null) {
final byte prefix = upperRange ? KEY_FIRST_PREFIX + 1 : KEY_FIRST_PREFIX;
final byte[] ret = ByteBuffer.allocate(PREFIX_SIZE)
.put(prefix)
.array();
return Bytes.wrap(ret);
}
final byte[] ret = ByteBuffer.allocate(PREFIX_SIZE + noPrefixKey.get().length)
.put(KEY_FIRST_PREFIX)
.put(noPrefixKey.get())
.array();
return Bytes.wrap(ret);
}
public static byte[] prefixNonPrefixSessionKey(final byte[] binaryKey) {
assert binaryKey != null;
return wrapPrefix(Bytes.wrap(binaryKey), false).get();
}
}
}