Mount Snapshot API

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Request

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The Mount Snapshot API mounts a snapshot as a searchable snapshot.

final MountSnapshotRequest request = new MountSnapshotRequest(
    "repository", 
    "snapshot", 
    "index" 
);
request.masterTimeout(TimeValue.timeValueSeconds(30)); 
request.waitForCompletion(true); 
request.storage(MountSnapshotRequest.Storage.FULL_COPY); 
request.renamedIndex("renamed_index"); 
final Settings indexSettings = Settings.builder()
    .put("index.number_of_replicas", 0)
    .build();
request.indexSettings(indexSettings); 
request.ignoredIndexSettings(
    new String[]{"index.refresh_interval"}); 

The name of the repository.

The name of the snapshot.

The name of the index in the snapshot to mount.

(optional) The period to wait for a connection to the master node.

(optional) If true, the request blocks until the operation is complete.

(optional) The type of local storage to use for the mounted snapshot.

(optional) The name of the index that will be created.

(optional) Settings that should be added to the mounted index.

(optional) Names of settings that should be unset when the index is mounted.

Response

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The returned MountSnapshotResponse indicates if the mounted snapshot was restored.

final RestoreInfo restoreInfo = response.getRestoreInfo(); 

The restore info of the mounted snapshot.

Synchronous execution

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When executing a MountSnapshotRequest in the following manner, the client waits for the MountSnapshotResponse to be returned before continuing with code execution:

final RestoreSnapshotResponse response = client
    .searchableSnapshots()
    .mountSnapshot(request, RequestOptions.DEFAULT);

Synchronous calls may throw an IOException in case of either failing to parse the REST response in the high-level REST client, the request times out or similar cases where there is no response coming back from the server.

In cases where the server returns a 4xx or 5xx error code, the high-level client tries to parse the response body error details instead and then throws a generic ElasticsearchException and adds the original ResponseException as a suppressed exception to it.

Asynchronous execution

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Executing a MountSnapshotRequest can also be done in an asynchronous fashion so that the client can return directly. Users need to specify how the response or potential failures will be handled by passing the request and a listener to the asynchronous searchable-snapshots-mount-snapshot method:

client.searchableSnapshots().mountSnapshotAsync(
    request,
    RequestOptions.DEFAULT,
    listener 
);

The MountSnapshotRequest to execute and the ActionListener to use when the execution completes

The asynchronous method does not block and returns immediately. Once it is completed the ActionListener is called back using the onResponse method if the execution successfully completed or using the onFailure method if it failed. Failure scenarios and expected exceptions are the same as in the synchronous execution case.

A typical listener for searchable-snapshots-mount-snapshot looks like:

ActionListener<RestoreSnapshotResponse> listener =
    new ActionListener<RestoreSnapshotResponse>() {

        @Override
        public void onResponse(
            final RestoreSnapshotResponse response) { 
            final RestoreInfo restoreInfo = response.getRestoreInfo();
        }

        @Override
        public void onFailure(final Exception e) {
            
        }

    };

Called when the execution is successfully completed.

Called when the whole MountSnapshotRequest fails.