KiFS API Support - Kinetica Docs

KiFS, while able to be managed in all native APIs, has enhanced support in the Java API.

API Initialization

When using KiFS via the Java API, the handler class must be initialized. The examples in the following sections make use of this interface and assume these steps have been taken.

KiFS API Imports

import com.gpudb.GPUdb;
import com.gpudb.GPUdbBase;
import com.gpudb.filesystem.GPUdbFileHandler;

KiFS API Initialization

// Establish connection with a running instance of Kinetica
GPUdbBase.Options options = new GPUdbBase.Options();
options.setUsername(user);
options.setPassword(pass);
GPUdb kdb = new GPUdb("http://" + host + ":9191", options);

// Acquire handle for KiFS interface
GPUdbFileHandler gfh = new GPUdbFileHandler(kdb);

Directories

In KiFS, a directory is a top-level container for files. A directory cannot be nested within another directory, though a file contained within a directory may have a path that gives the appearance of being contained within one or more nested virtual directories. A directory must exist before files can be uploaded into it.

Creating Directories

To create a KiFS directory, data:

Create Directory Example

gfh.createDirectory("data", false);

Showing Directories

To show the stats of a KiFS directory, data:

Show Directory Example

List<KifsDirectoryInfo> dirs = gfh.showDirectories("data", null);
for (KifsDirectoryInfo dir : dirs)
{
	System.out.println(dir.getKifsPath());
	System.out.println("* Created by: " + dir.getCreatedBy());
	System.out.println("* Created time: " + dir.getCreationTime());
}

To show the stats of all KiFS directories, pass null for the directory name:

Show All Directories Example

List<KifsDirectoryInfo> allDirs = gfh.showDirectories(null, null);
for (KifsDirectoryInfo dir : allDirs)
	System.out.println("* " + dir.getKifsPath());

Deleting Directories

To delete an empty, existing KiFS directory, use the following parameters:

data - name of the directory
false - don’t delete files contained within the directory, and return an error if any are found
false - return an error if the directory is not found

Delete Empty Directory Example

gfh.deleteDirectory("data", false, false);

To delete a KiFS directory, data, and all files contained within, regardless of whether the directory exists (similar to a Unix rm -rf):

data - name of the directory
true - delete any files contained within the directory
true - suppress the error in the case that the directory is not found

Delete Non-Empty Directory Example

gfh.deleteDirectory("data", true, true);

Files

In KiFS, a file is a user-uploaded text or binary object. Each file is located within a directory and must have a unique name within that directory. The name can contain forward slashes to create the appearance of a hierarchical virtual directory structure and help namespace the files. Overall, each file is referenced by the composite of the directory and file name.

Uploading Files

To upload a file to a KiFS directory, data, under a virtual directory, geo:

Upload Single File Example

gfh.upload("upload/data/csv/flights.csv", "data/geo", null, null);

To upload a set of files to a KiFS directory, data, under a virtual directory, geo:

Upload Multiple Files Example

// Add files to the list of files to upload
List<String> localFileNames = new ArrayList<>();
localFileNames.add("upload/programs/analyze-paths.jar");
localFileNames.add("upload/data/csv/flights.csv");

// Upload each file as data/geo/<filename>
//   All files, regardless of source path, will be placed directly
//   under "data/geo"
gfh.upload(localFileNames, "data/geo", null, null);

Listing Files

To list the KiFS files in a directory, data:

List Files Example

for (KifsFileInfo fileInfo : gfh.showFiles(Collections.singletonList("data")))
	System.out.println("* " + fileInfo.getFileName() + " (" + fileInfo.getFileSize() + "B)");

Downloading Files

To download a KiFS file to a local directory, download:

Download Single File Example

gfh.download("data/geo/flights.csv", "download", null, null);

To download a set of KiFS files to a local directory, download:

Download Multiple Files Example

List<String> remoteFileNames = new ArrayList<>();
remoteFileNames.add("data/geo/analyze-paths.jar");
remoteFileNames.add("data/geo/flights.csv");

gfh.download(remoteFileNames, "download", null, null);

Deleting Files

To delete a set of KiFS files:

Delete Multiple Files Example

List<String> remoteFileNames = new ArrayList<>();
remoteFileNames.add("data/geo/analyze-paths.jar");
remoteFileNames.add("data/geo/flights.csv");

gfh.deleteFiles(remoteFileNames);

KiFS Endpoints

The following REST API endpoint calls can also be used to manage KiFS.

API Call	Description
/create/directory	Creates a directory, a container for files
/delete/directory	Removes the directory; can optionally remove all contained files
/show/directories	Outputs the properties of one or more specified directories, or optionally, all directories
/grant/permission/directory	Grants the permission for a user to access files within a directory
/revoke/permission/directory	Revokes the permission for a user to access files within a directory
/delete/files	Removes one or more files
/download/files	Downloads one or more files
/show/files	Outputs the properties of one or more files
/upload/files	Uploads one or more files to a directory

​API Initialization

​Directories

​Creating Directories

​Showing Directories

​Deleting Directories

​Files

​Uploading Files

​Listing Files

​Downloading Files

​Deleting Files

​KiFS Endpoints