Remove deprecated Repository methods (#42359)

We deprecated `restoreShard` and `snapshotShard` in #42213
This change removes the deprecated methods and their usage and adds
a note in the migration docs.

docs/reference/migration/migrate_8_0/java.asciidoc

@@ -25,3 +25,11 @@ while silently truncating them to one of the three allowed edit distances 0, 1
 or 2. This leniency is now removed and the class will throw errors when trying
 to construct an instance with another value (e.g. floats like 1.3 used to get
 accepted but truncated to 1). You should use one of the allowed values.
+
+
+[float]
+==== Changes to Repository
+
+Repository has no dependency on IndexShard anymore. The contract of restoreShard
+and snapshotShard has been reduced to Store and MappingService in order to improve
+testability.

server/src/main/java/org/elasticsearch/index/shard/StoreRecovery.java

@@ -469,7 +469,7 @@ final class StoreRecovery {
             }
             final IndexId indexId = repository.getRepositoryData().resolveIndexId(indexName);
             assert indexShard.getEngineOrNull() == null;
-            repository.restoreShard(indexShard, indexShard.store(), restoreSource.snapshot().getSnapshotId(),
+            repository.restoreShard(indexShard.store(), restoreSource.snapshot().getSnapshotId(),
                 restoreSource.version(), indexId, snapshotShardId, indexShard.recoveryState());
             final Store store = indexShard.store();
             store.bootstrapNewHistory();

server/src/main/java/org/elasticsearch/repositories/Repository.java

@@ -27,7 +27,6 @@ import org.elasticsearch.cluster.metadata.RepositoryMetaData;
 import org.elasticsearch.cluster.node.DiscoveryNode;
 import org.elasticsearch.common.component.LifecycleComponent;
 import org.elasticsearch.index.mapper.MapperService;
-import org.elasticsearch.index.shard.IndexShard;
 import org.elasticsearch.index.shard.ShardId;
 import org.elasticsearch.index.snapshots.IndexShardSnapshotStatus;
 import org.elasticsearch.index.store.Store;
@@ -189,27 +188,6 @@ public interface Repository extends LifecycleComponent {
      */
     boolean isReadOnly();
 
-    /**
-     * Creates a snapshot of the shard based on the index commit point.
-     * <p>
-     * The index commit point can be obtained by using {@link org.elasticsearch.index.engine.Engine#acquireLastIndexCommit} method.
-     * Repository implementations shouldn't release the snapshot index commit point. It is done by the method caller.
-     * <p>
-     * As snapshot process progresses, implementation of this method should update {@link IndexShardSnapshotStatus} object and check
-     * {@link IndexShardSnapshotStatus#isAborted()} to see if the snapshot process should be aborted.
-     * @param indexShard          the shard to be snapshotted
-     * @param snapshotId          snapshot id
-     * @param indexId             id for the index being snapshotted
-     * @param snapshotIndexCommit commit point
-     * @param snapshotStatus      snapshot status
-     * @deprecated use {@link #snapshotShard(Store, MapperService, SnapshotId, IndexId, IndexCommit, IndexShardSnapshotStatus)} instead
-     */
-    @Deprecated
-    default void snapshotShard(IndexShard indexShard, SnapshotId snapshotId, IndexId indexId, IndexCommit snapshotIndexCommit,
-                       IndexShardSnapshotStatus snapshotStatus) {
-        snapshotShard(indexShard.store(), indexShard.mapperService(), snapshotId, indexId, snapshotIndexCommit, snapshotStatus);
-    }
-
     /**
      * Creates a snapshot of the shard based on the index commit point.
      * <p>
@@ -228,25 +206,6 @@ public interface Repository extends LifecycleComponent {
     void snapshotShard(Store store, MapperService mapperService, SnapshotId snapshotId, IndexId indexId, IndexCommit snapshotIndexCommit,
                        IndexShardSnapshotStatus snapshotStatus);
 
-    /**
-     * Restores snapshot of the shard.
-     * <p>
-     * The index can be renamed on restore, hence different {@code shardId} and {@code snapshotShardId} are supplied.
-     * @param shard           the shard to restore the index into
-     * @param store           the store to restore the index into
-     * @param snapshotId      snapshot id
-     * @param version         version of elasticsearch that created this snapshot
-     * @param indexId         id of the index in the repository from which the restore is occurring
-     * @param snapshotShardId shard id (in the snapshot)
-     * @param recoveryState   recovery state
-     * @deprecated use {@link #restoreShard(Store, SnapshotId, Version, IndexId, ShardId, RecoveryState)} instead
-     */
-    @Deprecated
-    default void restoreShard(IndexShard shard, Store store, SnapshotId snapshotId, Version version, IndexId indexId,
-                              ShardId snapshotShardId, RecoveryState recoveryState) {
-        restoreShard(store, snapshotId, version, indexId, snapshotShardId, recoveryState);
-    }
-
     /**
      * Restores snapshot of the shard.
      * <p>

server/src/main/java/org/elasticsearch/snapshots/SnapshotShardsService.java

@@ -367,7 +367,8 @@ public class SnapshotShardsService extends AbstractLifecycleComponent implements
         try {
             // we flush first to make sure we get the latest writes snapshotted
             try (Engine.IndexCommitRef snapshotRef = indexShard.acquireLastIndexCommit(true)) {
-                repository.snapshotShard(indexShard, snapshot.getSnapshotId(), indexId, snapshotRef.getIndexCommit(), snapshotStatus);
+                repository.snapshotShard(indexShard.store(), indexShard.mapperService(), snapshot.getSnapshotId(), indexId,
+                    snapshotRef.getIndexCommit(), snapshotStatus);
                 if (logger.isDebugEnabled()) {
                     final IndexShardSnapshotStatus.Copy lastSnapshotStatus = snapshotStatus.asCopy();
                     logger.debug("snapshot ({}) completed to {} with {}", snapshot, repository, lastSnapshotStatus);