[SPARK-54346][SS] Introduce state repartition API and repartition runner

common/utils-java/src/main/java/org/apache/spark/internal/LogKeys.java

@@ -192,6 +192,7 @@ public enum LogKeys implements LogKey {
   END_INDEX,
   END_POINT,
   END_VERSION,
+  ENFORCE_EXACTLY_ONCE,
   ENGINE,
   EPOCH,
   ERROR,

common/utils/src/main/resources/error/error-conditions.json

@@ -5265,6 +5265,85 @@
     ],
     "sqlState" : "42802"
   },
+  "STATE_REPARTITION_INVALID_CHECKPOINT" : {
+    "message" : [
+      "The provided checkpoint location '<checkpointLocation>' is in an invalid state."
+    ],
+    "subClass" : {
+      "LAST_BATCH_ABANDONED_REPARTITION" : {
+        "message" : [
+          "The last batch ID <lastBatchId> is a repartition batch with <lastBatchShufflePartitions> shuffle partitions and didn't finish successfully.",
+          "You're now requesting to repartition to <numPartitions> shuffle partitions.",
+          "Please retry with the same number of shuffle partitions as the previous attempt.",
+          "Once that completes successfully, you can repartition to another number of shuffle partitions."
+        ]
+      },
+      "LAST_BATCH_FAILED" : {
+        "message" : [
+          "The last batch ID <lastBatchId> didn't finish successfully. Please make sure the streaming query finishes successfully, before repartitioning.",
+          "If using ProcessingTime trigger, you can use AvailableNow trigger instead, which will make sure the query terminates successfully by itself.",
+          "If you want to skip this check, set enforceExactlyOnceSink parameter in repartition to false.",
+          "But this can cause duplicate output records from the failed batch when using exactly-once sinks."
+        ]
+      },
+      "MISSING_OFFSET_SEQ_METADATA" : {
+        "message" : [
+          "The OffsetSeq (v<version>) metadata is missing for batch ID <batchId>. Please make sure the checkpoint is from a supported Spark version."
+        ]
+      },
+      "NO_BATCH_FOUND" : {
+        "message" : [
+          "No microbatch has been recorded in the checkpoint location. Make sure the streaming query has successfully completed at least one microbatch before repartitioning."
+        ]
+      },
+      "NO_COMMITTED_BATCH" : {
+        "message" : [
+          "There is no committed microbatch. Make sure the streaming query has successfully completed at least one microbatch before repartitioning."
+        ]
+      },
+      "OFFSET_SEQ_NOT_FOUND" : {
+        "message" : [
+          "Offset sequence entry for batch ID <batchId> not found. You might have set a very low value for",
+          "'spark.sql.streaming.minBatchesToRetain' config during the streaming query execution or you deleted files in the checkpoint location."
+        ]
+      },
+      "SHUFFLE_PARTITIONS_ALREADY_MATCH" : {
+        "message" : [
+          "The number of shuffle partitions in the last committed batch (id=<batchId>) is the same as the requested <numPartitions> partitions.",
+          "Hence, already has the requested number of partitions, so no-op."
+        ]
+      },
+      "UNSUPPORTED_OFFSET_SEQ_VERSION" : {
+        "message" : [
+          "Unsupported offset sequence version <version>. Please make sure the checkpoint is from a supported Spark version."
+        ]
+      }
+    },
+    "sqlState" : "55019"
+  },
+  "STATE_REPARTITION_INVALID_PARAMETER" : {
+    "message" : [
+      "The repartition parameter <parameter> is invalid:"
+    ],
+    "subClass" : {
+      "IS_EMPTY" : {
+        "message" : [
+          "cannot be empty."
+        ]
+      },
+      "IS_NOT_GREATER_THAN_ZERO" : {
+        "message" : [
+          "must be greater than zero."
+        ]
+      },
+      "IS_NULL" : {
+        "message" : [
+          "cannot be null."
+        ]
+      }
+    },
+    "sqlState" : "42616"
+  },
   "STATE_STORE_CANNOT_CREATE_COLUMN_FAMILY_WITH_RESERVED_CHARS" : {
     "message" : [
       "Failed to create column family with unsupported starting character and name=<colFamilyName>."

sql/api/src/main/scala/org/apache/spark/sql/streaming/StreamingCheckpointManager.scala

@@ -0,0 +1,53 @@
+/*
+ * 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.streaming
+
+/**
+ * A class to manage operations on streaming query checkpoints.
+ */
+private[spark] abstract class StreamingCheckpointManager {
+
+  /**
+   * Repartition the stateful streaming operators state in the streaming checkpoint to have
+   * `numPartitions` partitions. The streaming query MUST not be running. If `numPartitions` is
+   * the same as the current number of partitions, this is a no-op, and an exception will be
+   * thrown.
+   *
+   * This produces a new microbatch in the checkpoint that contains the repartitioned state i.e.
+   * if the last streaming batch was batch `N`, this will create batch `N+1` with the
+   * repartitioned state. Note that this new batch doesn't read input data from sources, it only
+   * represents the repartition operation. The next time the streaming query is started, it will
+   * pick up from this new batch.
+   *
+   * This will return only when the repartitioning is complete or fails.
+   *
+   * @note
+   *   This operation should only be performed after the streaming query has been stopped.
+   * @param checkpointLocation
+   *   The checkpoint location of the streaming query, should be the `checkpointLocation` option
+   *   on the DataStreamWriter.
+   * @param numPartitions
+   *   the target number of state partitions.
+   * @param enforceExactlyOnceSink
+   *   if we shouldn't allow skipping failed batches, to avoid duplicates in exactly once sinks.
+   */
+  private[spark] def repartition(
+      checkpointLocation: String,
+      numPartitions: Int,
+      enforceExactlyOnceSink: Boolean = true): Unit
+}

sql/core/src/main/scala/org/apache/spark/sql/classic/SQLContext.scala

@@ -145,6 +145,12 @@ class SQLContext private[sql] (override val sparkSession: SparkSession)
    */
   def streams: StreamingQueryManager = sparkSession.streams
 
+  /**
+   * Returns a `StreamingCheckpointManager` that allows managing any streaming checkpoint.
+   */
+  private[spark] def streamingCheckpointManager: StreamingCheckpointManager =
+    sparkSession.streamingCheckpointManager
+
   /** @inheritdoc */
   override def sparkContext: SparkContext = super.sparkContext
 

sql/core/src/main/scala/org/apache/spark/sql/classic/SparkSession.scala

@@ -223,6 +223,8 @@ class SparkSession private(
   @Unstable
   def streams: StreamingQueryManager = sessionState.streamingQueryManager
 
+  private[spark] def streamingCheckpointManager = sessionState.streamingCheckpointManager
+
   /**
    * Returns an `ArtifactManager` that supports adding, managing and using session-scoped artifacts
    * (jars, classfiles, etc).

sql/core/src/main/scala/org/apache/spark/sql/classic/StreamingCheckpointManager.scala

@@ -0,0 +1,55 @@
+/*
+ * 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.classic
+
+import org.apache.spark.internal.Logging
+import org.apache.spark.sql.execution.streaming.state.{OfflineStateRepartitionErrors, OfflineStateRepartitionRunner}
+import org.apache.spark.sql.internal.SQLConf
+import org.apache.spark.sql.streaming
+
+/** @inheritdoc */
+private[spark] class StreamingCheckpointManager(
+    sparkSession: SparkSession,
+    sqlConf: SQLConf) extends streaming.StreamingCheckpointManager with Logging {
+
+  /** @inheritdoc */
+  override private[spark] def repartition(
+      checkpointLocation: String,
+      numPartitions: Int,
+      enforceExactlyOnceSink: Boolean = true): Unit = {
+    checkpointLocation match {
+      case null =>
+        throw OfflineStateRepartitionErrors.parameterIsNullError("checkpointLocation")
+      case "" =>
+        throw OfflineStateRepartitionErrors.parameterIsEmptyError("checkpointLocation")
+      case _ => // Valid case, no action needed
+    }
+
+    if (numPartitions <= 0) {
+      throw OfflineStateRepartitionErrors.parameterIsNotGreaterThanZeroError("numPartitions")
+    }
+
+    val runner = new OfflineStateRepartitionRunner(
+      sparkSession,
+      checkpointLocation,
+      numPartitions,
+      enforceExactlyOnceSink
+    )
+    runner.run()
+  }
+}

sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/v2/state/StateDataSource.scala

@@ -42,6 +42,7 @@ import org.apache.spark.sql.execution.streaming.operators.stateful.transformwith
 import org.apache.spark.sql.execution.streaming.runtime.StreamingCheckpointConstants.DIR_NAME_STATE
 import org.apache.spark.sql.execution.streaming.runtime.StreamingQueryCheckpointMetadata
 import org.apache.spark.sql.execution.streaming.state.{InMemoryStateSchemaProvider, KeyStateEncoderSpec, NoPrefixKeyStateEncoderSpec, PrefixKeyScanStateEncoderSpec, StateSchemaCompatibilityChecker, StateSchemaMetadata, StateSchemaProvider, StateStore, StateStoreColFamilySchema, StateStoreConf, StateStoreId, StateStoreProviderId}
+import org.apache.spark.sql.execution.streaming.utils.StreamingUtils
 import org.apache.spark.sql.sources.DataSourceRegister
 import org.apache.spark.sql.streaming.TimeMode
 import org.apache.spark.sql.types.StructType
@@ -481,7 +482,8 @@ object StateSourceOptions extends DataSourceOptions {
       throw StateDataSourceErrors.conflictOptions(Seq(JOIN_SIDE, STORE_NAME))
     }
 
-    val resolvedCpLocation = resolvedCheckpointLocation(hadoopConf, checkpointLocation)
+    val resolvedCpLocation = StreamingUtils.resolvedCheckpointLocation(
+      hadoopConf, checkpointLocation)
 
     var batchId = Option(options.get(BATCH_ID)).map(_.toLong)
 
@@ -617,14 +619,6 @@ object StateSourceOptions extends DataSourceOptions {
       startOperatorStateUniqueIds, endOperatorStateUniqueIds)
   }
 
-  private def resolvedCheckpointLocation(
-      hadoopConf: Configuration,
-      checkpointLocation: String): String = {
-    val checkpointPath = new Path(checkpointLocation)
-    val fs = checkpointPath.getFileSystem(hadoopConf)
-    checkpointPath.makeQualified(fs.getUri, fs.getWorkingDirectory).toUri.toString
-  }
-
   private def getLastCommittedBatch(session: SparkSession, checkpointLocation: String): Long = {
     val commitLog = new StreamingQueryCheckpointMetadata(session, checkpointLocation).commitLog
     commitLog.getLatest() match {