Flink GS FileSystem Hadoop

import org.apache.flink.core.fs.FileSystem;
import org.apache.flink.core.fs.Path;

// FileSystem is automatically discovered and configured
Path gcsPath = new Path("gs://my-bucket/data/file.txt");
FileSystem fs = gcsPath.getFileSystem();

// Use for reading/writing files
FSDataInputStream inputStream = fs.open(gcsPath);
FSDataOutputStream outputStream = fs.create(gcsPath, WriteMode.OVERWRITE);

# Authentication via service account
fs.gs.auth.service.account.enable=true
fs.gs.auth.service.account.json.keyfile=/path/to/service-account.json

# Performance tuning
gs.writer.chunk.size=8MB
gs.filesink.entropy.enabled=true

# Retry configuration
gs.retry.max-attempt=10
gs.retry.total-timeout=300s

// Main factory class registered via META-INF services
public class GSFileSystemFactory implements FileSystemFactory {
    public static final String SCHEME = "gs";
    
    public void configure(Configuration flinkConfig);
    public String getScheme();
    public FileSystem create(URI fsUri) throws IOException;
}

// Configuration options container
public class GSFileSystemOptions {
    public Optional<String> getWriterTemporaryBucketName();
    public Optional<MemorySize> getWriterChunkSize();
    public Boolean isFileSinkEntropyEnabled();
    public Optional<Integer> getHTTPConnectionTimeout();
    public Optional<Integer> getHTTPReadTimeout();
    // ... retry configuration methods
}

// Main recoverable writer interface
public class GSRecoverableWriter implements RecoverableWriter {
    public boolean requiresCleanupOfRecoverableState();
    public boolean supportsResume();
    public RecoverableFsDataOutputStream open(Path path) throws IOException;
    public RecoverableFsDataOutputStream recover(ResumeRecoverable resumable);
    public RecoverableFsDataOutputStream.Committer recoverForCommit(CommitRecoverable resumable);
    public SimpleVersionedSerializer<CommitRecoverable> getCommitRecoverableSerializer();
    public SimpleVersionedSerializer<ResumeRecoverable> getResumeRecoverableSerializer();
}

// State objects for recovery
public class GSCommitRecoverable implements RecoverableWriter.CommitRecoverable {
    public final GSBlobIdentifier finalBlobIdentifier;
    public final List<UUID> componentObjectIds;
}

public class GSResumeRecoverable extends GSCommitRecoverable 
    implements RecoverableWriter.ResumeRecoverable {
    public final long position;
    public final boolean closed;
}

// Storage abstraction interface
public interface GSBlobStorage {
    WriteChannel writeBlob(GSBlobIdentifier blobIdentifier);
    WriteChannel writeBlob(GSBlobIdentifier blobIdentifier, MemorySize chunkSize);
    void createBlob(GSBlobIdentifier blobIdentifier);
    Optional<BlobMetadata> getMetadata(GSBlobIdentifier blobIdentifier);
    List<GSBlobIdentifier> list(String bucketName, String prefix);
    void copy(GSBlobIdentifier sourceBlobIdentifier, GSBlobIdentifier targetBlobIdentifier);
    void compose(List<GSBlobIdentifier> sourceBlobIdentifiers, GSBlobIdentifier targetBlobIdentifier);
    List<Boolean> delete(Iterable<GSBlobIdentifier> blobIdentifiers);
}

// Blob identifier abstraction
public class GSBlobIdentifier {
    public final String bucketName;
    public final String objectName;
    
    public GSBlobIdentifier(String bucketName, String objectName);
    public BlobId getBlobId();
    public static GSBlobIdentifier fromBlobId(BlobId blobId);
}