ericm-db commented on code in PR #45991: URL: https://github.com/apache/spark/pull/45991#discussion_r1571071937
########## sql/core/src/main/scala/org/apache/spark/sql/execution/streaming/MapStateImplWithTTL.scala: ########## @@ -0,0 +1,277 @@ +/* + * 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.spark.sql.execution.streaming + +import org.apache.spark.internal.Logging +import org.apache.spark.sql.Encoder +import org.apache.spark.sql.catalyst.encoders.ExpressionEncoder +import org.apache.spark.sql.execution.streaming.TransformWithStateKeyValueRowSchema.{COMPOSITE_KEY_ROW_SCHEMA, VALUE_ROW_SCHEMA_WITH_TTL} +import org.apache.spark.sql.execution.streaming.state.{PrefixKeyScanStateEncoderSpec, StateStore, StateStoreErrors} +import org.apache.spark.sql.streaming.{MapState, TTLConfig} +import org.apache.spark.util.NextIterator + +/** + * Class that provides a concrete implementation for map state associated with state + * variables (with ttl expiration support) used in the streaming transformWithState operator. + * @param store - reference to the StateStore instance to be used for storing state + * @param stateName - name of the state variable + * @param keyExprEnc - Spark SQL encoder for key + * @param userKeyEnc - Spark SQL encoder for the map key + * @param valEncoder - SQL encoder for state variable + * @param ttlConfig - the ttl configuration (time to live duration etc.) + * @tparam K - type of key for map state variable + * @tparam V - type of value for map state variable + * @return - instance of MapState of type [K,V] that can be used to store state persistently + */ +class MapStateImplWithTTL[K, V]( + store: StateStore, + stateName: String, + keyExprEnc: ExpressionEncoder[Any], + userKeyEnc: Encoder[K], + valEncoder: Encoder[V], + ttlConfig: TTLConfig, + batchTimestampMs: Long) extends CompositeKeyTTLStateImpl(stateName, store, batchTimestampMs) + with MapState[K, V] with Logging { + + private val keySerializer = keyExprEnc.createSerializer() + private val stateTypesEncoder = new CompositeKeyStateEncoder( + keySerializer, userKeyEnc, valEncoder, COMPOSITE_KEY_ROW_SCHEMA, stateName, hasTtl = true) + + private val ttlExpirationMs = + StateTTL.calculateExpirationTimeForDuration(ttlConfig.ttlDuration, batchTimestampMs) + + initialize() + + private def initialize(): Unit = { + store.createColFamilyIfAbsent(stateName, COMPOSITE_KEY_ROW_SCHEMA, VALUE_ROW_SCHEMA_WITH_TTL, + PrefixKeyScanStateEncoderSpec(COMPOSITE_KEY_ROW_SCHEMA, 1)) + } + + /** Whether state exists or not. */ + override def exists(): Boolean = { + iterator().nonEmpty + } + + /** Get the state value if it exists */ + override def getValue(key: K): V = { + StateStoreErrors.requireNonNullStateValue(key, stateName) + val encodedCompositeKey = stateTypesEncoder.encodeCompositeKey(key) + val retRow = store.get(encodedCompositeKey, stateName) + + if (retRow != null) { + val resState = stateTypesEncoder.decodeValue(retRow) + + if (!stateTypesEncoder.isExpired(retRow, batchTimestampMs)) { + resState + } else { + null.asInstanceOf[V] + } + } else { + null.asInstanceOf[V] + } + } + + /** Check if the user key is contained in the map */ + override def containsKey(key: K): Boolean = { + StateStoreErrors.requireNonNullStateValue(key, stateName) + getValue(key) != null + } + + /** Update value for given user key */ + override def updateValue(key: K, value: V): Unit = { + StateStoreErrors.requireNonNullStateValue(key, stateName) + StateStoreErrors.requireNonNullStateValue(value, stateName) + val encodedValue = stateTypesEncoder.encodeValue(value, ttlExpirationMs) + val encodedCompositeKey = stateTypesEncoder.encodeCompositeKey(key) + store.put(encodedCompositeKey, encodedValue, stateName) + val serializedGroupingKey = stateTypesEncoder.serializeGroupingKey() + val serializedUserKey = stateTypesEncoder.serializeUserKey(key) + upsertTTLForStateKey(ttlExpirationMs, serializedGroupingKey, serializedUserKey) + } + + /** Get the map associated with grouping key */ + override def iterator(): Iterator[(K, V)] = { + val encodedGroupingKey = stateTypesEncoder.encodeGroupingKey() + val unsafeRowPairIterator = store.prefixScan(encodedGroupingKey, stateName) + new NextIterator[(K, V)] { + override protected def getNext(): (K, V) = { + val iter = unsafeRowPairIterator.dropWhile { rowPair => Review Comment: Well we are only creating the underlying unsafeRowPairIterator once, when the user calls `iterator`. Using `dropWhile` in each getNext call is essentially what we would be doing anyways - looping until we find a non-expired key-value pair. -- 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: reviews-unsubscr...@spark.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For additional commands, e-mail: reviews-h...@spark.apache.org
