io.delta.kernel.engine

Interface FileSystemClient

All Known Implementing Classes:

DefaultFileSystemClient

@Evolving
public interface FileSystemClient

Provides file system related functionalities to Delta Kernel. Delta Kernel uses this client whenever it needs to access the underlying file system where the Delta table is present. Connector implementation of this interface can hide filesystem specific details from Delta Kernel.

Since:

3.0.0

Method Summary

Modifier and Type	Method and Description
boolean	delete(String path) Delete the file at given path.
CloseableIterator<FileStatus>	listFrom(String filePath) List the paths in the same directory that are lexicographically greater or equal to (UTF-8 sorting) the given `path`.
boolean	mkdirs(String path) Create a directory at the given path including parent directories.
CloseableIterator<java.io.ByteArrayInputStream>	readFiles(CloseableIterator<FileReadRequest> readRequests) Return an iterator of byte streams one for each read request in readRequests.
String	resolvePath(String path) Resolve the given path to a fully qualified path.

Method Detail

listFrom

CloseableIterator<FileStatus> listFrom(String filePath)
                                throws java.io.IOException

List the paths in the same directory that are lexicographically greater or equal to (UTF-8 sorting) the given `path`. The result should also be sorted by the file name.

Parameters:

filePath - Fully qualified path to a file

Returns:

Closeable iterator of files. It is the responsibility of the caller to close the iterator.

Throws:

java.io.FileNotFoundException - if the file at the given path is not found

java.io.IOException - for any other IO error.

resolvePath

String resolvePath(String path)
            throws java.io.IOException

Resolve the given path to a fully qualified path.

Parameters:

path - Input path

Returns:

Fully qualified path.

Throws:

java.io.FileNotFoundException - If the given path doesn't exist.

java.io.IOException - for any other IO error.

readFiles

CloseableIterator<java.io.ByteArrayInputStream> readFiles(CloseableIterator<FileReadRequest> readRequests)
                                                   throws java.io.IOException

Return an iterator of byte streams one for each read request in readRequests. The returned streams are in the same order as the given FileReadRequests. It is the responsibility of the caller to close each returned stream.

Parameters:

readRequests - Iterator of read requests

Returns:

Data for each request as one ByteArrayInputStream.

Throws:

java.io.IOException

mkdirs

boolean mkdirs(String path)
        throws java.io.IOException

Create a directory at the given path including parent directories. This mimicks the behavior of `mkdir -p` in Unix.

Parameters:

path - Full qualified path to create a directory at.

Returns:

true if the directory was created successfully, false otherwise.

Throws:

java.io.IOException - for any IO error.

delete

boolean delete(String path)
        throws java.io.IOException

Delete the file at given path.

Parameters:

path - the path to delete. If path is a directory throws an exception.

Returns:

true if delete is successful else false.

Throws:

java.io.IOException - for any IO error.