Removed duplicate deleteBlob methods (#18813)

Removed the following methods from the
BlobContainer interface to clean up the interface:

1) deleteBlobs
2) deleteBlobsByPrefix

Closes #18529

core/src/main/java/org/elasticsearch/common/blobstore/BlobContainer.java

@@ -99,35 +99,6 @@ public interface BlobContainer {
      */
     void deleteBlob(String blobName) throws IOException;
 
-    /**
-     * Deletes blobs with the given names.  If any subset of the names do not exist in the container, this method has no
-     * effect for those names, and will delete the blobs for those names that do exist.  If any of the blobs failed
-     * to delete, those blobs that were processed before it and successfully deleted will remain deleted.  An exception
-     * is thrown at the first blob entry that fails to delete (TODO: is this the right behavior?  Should we collect
-     * all the failed deletes into a single IOException instead?)
-     *
-     * TODO: remove, see https://github.com/elastic/elasticsearch/issues/18529
-     *
-     * @param   blobNames
-     *          The collection of blob names to delete from the container.
-     * @throws  IOException if any of the blobs in the collection exists but could not be deleted.
-     */
-    void deleteBlobs(Collection<String> blobNames) throws IOException;
-
-    /**
-     * Deletes all blobs in the container that match the specified prefix.  If any of the blobs failed to delete,
-     * those blobs that were processed before it and successfully deleted will remain deleted.  An exception is
-     * thrown at the first blob entry that fails to delete (TODO: is this the right behavior?  Should we collect
-     * all the failed deletes into a single IOException instead?)
-     *
-     * TODO: remove, see: https://github.com/elastic/elasticsearch/issues/18529
-     *
-     * @param   blobNamePrefix
-     *          The prefix to match against blob names in the container.  Any blob whose name has the prefix will be deleted.
-     * @throws  IOException if any of the matching blobs failed to delete.
-     */
-    void deleteBlobsByPrefix(String blobNamePrefix) throws IOException;
-
     /**
      * Lists all blobs in the container.
      *

core/src/main/java/org/elasticsearch/common/blobstore/support/AbstractBlobContainer.java

@@ -45,21 +45,6 @@ public abstract class AbstractBlobContainer implements BlobContainer {
         return this.path;
     }
 
-    @Override
-    public void deleteBlobsByPrefix(final String blobNamePrefix) throws IOException {
-        Map<String, BlobMetaData> blobs = listBlobsByPrefix(blobNamePrefix);
-        for (BlobMetaData blob : blobs.values()) {
-            deleteBlob(blob.name());
-        }
-    }
-
-    @Override
-    public void deleteBlobs(Collection<String> blobNames) throws IOException {
-        for (String blob: blobNames) {
-            deleteBlob(blob);
-        }
-    }
-
     @Override
     public void writeBlob(String blobName, BytesReference bytes) throws IOException {
         try (InputStream stream = bytes.streamInput()) {

core/src/main/java/org/elasticsearch/repositories/blobstore/BlobStoreRepository.java

@@ -970,37 +970,33 @@ public abstract class BlobStoreRepository extends AbstractLifecycleComponent imp
          */
         protected void finalize(List<SnapshotFiles> snapshots, int fileListGeneration, Map<String, BlobMetaData> blobs) {
             BlobStoreIndexShardSnapshots newSnapshots = new BlobStoreIndexShardSnapshots(snapshots);
-            List<String> blobsToDelete = new ArrayList<>();
             // delete old index files first
             for (String blobName : blobs.keySet()) {
-                // delete old file lists
                 if (indexShardSnapshotsFormat.isTempBlobName(blobName) || blobName.startsWith(SNAPSHOT_INDEX_PREFIX)) {
-                    blobsToDelete.add(blobName);
-                }
-            }
-
                     try {
-                blobContainer.deleteBlobs(blobsToDelete);
+                        blobContainer.deleteBlob(blobName);
                     } catch (IOException e) {
                         // We cannot delete index file - this is fatal, we cannot continue, otherwise we might end up
                         // with references to non-existing files
-                throw new IndexShardSnapshotFailedException(shardId, "error deleting index files during cleanup", e);
+                        throw new IndexShardSnapshotFailedException(shardId, "error deleting index file ["
+                            + blobName + "] during cleanup", e);
+                    }
+                }
             }
 
-            blobsToDelete = new ArrayList<>();
+            // now go over all the blobs, and if they don't exist in a snapshot, delete them
-            // now go over all the blobs, and if they don't exists in a snapshot, delete them
             for (String blobName : blobs.keySet()) {
                 // delete unused files
                 if (blobName.startsWith(DATA_BLOB_PREFIX)) {
                     if (newSnapshots.findNameFile(BlobStoreIndexShardSnapshot.FileInfo.canonicalName(blobName)) == null) {
-                        blobsToDelete.add(blobName);
-                    }
-                }
-            }
                         try {
-                blobContainer.deleteBlobs(blobsToDelete);
+                            blobContainer.deleteBlob(blobName);
                         } catch (IOException e) {
-                logger.debug("[{}] [{}] error deleting some of the blobs [{}] during cleanup", e, snapshotId, shardId, blobsToDelete);
+                            // TODO: don't catch and let the user handle it?
+                            logger.debug("[{}] [{}] error deleting blob [{}] during cleanup", e, snapshotId, shardId, blobName);
+                        }
+                    }
+                }
             }
 
             // If we deleted all snapshots - we don't need to create the index file

core/src/test/java/org/elasticsearch/snapshots/mockstore/BlobContainerWrapper.java

@@ -68,16 +68,6 @@ public class BlobContainerWrapper implements BlobContainer {
         delegate.deleteBlob(blobName);
     }
 
-    @Override
-    public void deleteBlobs(Collection<String> blobNames) throws IOException {
-        delegate.deleteBlobs(blobNames);
-    }
-
-    @Override
-    public void deleteBlobsByPrefix(String blobNamePrefix) throws IOException {
-        delegate.deleteBlobsByPrefix(blobNamePrefix);
-    }
-
     @Override
     public Map<String, BlobMetaData> listBlobs() throws IOException {
         return delegate.listBlobs();

core/src/test/java/org/elasticsearch/snapshots/mockstore/MockRepository.java

@@ -299,12 +299,6 @@ public class MockRepository extends FsRepository {
                 super.deleteBlob(blobName);
             }
 
-            @Override
-            public void deleteBlobsByPrefix(String blobNamePrefix) throws IOException {
-                maybeIOExceptionOrBlock(blobNamePrefix);
-                super.deleteBlobsByPrefix(blobNamePrefix);
-            }
-
             @Override
             public Map<String, BlobMetaData> listBlobs() throws IOException {
                 maybeIOExceptionOrBlock("");

plugins/repository-gcs/src/main/java/org/elasticsearch/common/blobstore/gcs/GoogleCloudStorageBlobContainer.java

@@ -84,16 +84,6 @@ public class GoogleCloudStorageBlobContainer extends AbstractBlobContainer {
         blobStore.deleteBlob(buildKey(blobName));
     }
 
-    @Override
-    public void deleteBlobsByPrefix(String prefix) throws IOException {
-        blobStore.deleteBlobsByPrefix(buildKey(prefix));
-    }
-
-    @Override
-    public void deleteBlobs(Collection<String> blobNames) throws IOException {
-        blobStore.deleteBlobs(buildKeys(blobNames));
-    }
-
     @Override
     public void move(String sourceBlobName, String targetBlobName) throws IOException {
         blobStore.moveBlob(buildKey(sourceBlobName), buildKey(targetBlobName));
@@ -103,12 +93,4 @@ public class GoogleCloudStorageBlobContainer extends AbstractBlobContainer {
         assert blobName != null;
         return path + blobName;
     }
-
-    protected Set<String> buildKeys(Collection<String> blobNames) {
-        Set<String> keys = new HashSet<>();
-        if (blobNames != null) {
-            keys.addAll(blobNames.stream().map(this::buildKey).collect(Collectors.toList()));
-        }
-        return keys;
-    }
 }