Struct DataSource 

pub struct DataSource { /* private fields */ }

Local-file abstraction with transparent gzip decompression.

Analogue of numpy.lib.npyio.DataSource. Wraps an optional base directory; open(name) resolves name relative to the base (if any) and opens the file, transparently decompressing it when the path ends in .gz.

URL fetching, the bz2/zstd formats, and the auto-cache behavior of NumPy’s class are not implemented — for remote sources, fetch via the project’s safe-fetch path first, then point DataSource at the local copy.

Implementations

impl DataSource

pub fn new(base: Option<PathBuf>) -> Self

Create a new DataSource. If base is Some, paths passed to open and exists are resolved relative to it.

pub fn abspath(&self, name: &str) -> FerrayResult<PathBuf>

Resolve a name (relative to base, if set) to an absolute path.

Errors

Returns FerrayError::IoError if std::path::absolute fails to canonicalize the path (e.g. permission errors on the parent).

pub fn exists(&self, name: &str) -> bool

Whether the named file exists relative to the base directory.

pub fn open(&self, name: &str) -> FerrayResult<DataSourceReader>

Open a file for reading.

If name ends in .gz, the returned reader transparently decompresses on the fly.

Errors

Returns FerrayError::IoError if the file cannot be opened.

pub fn open_path<P: AsRef<Path>>(path: P) -> FerrayResult<DataSourceReader>

Open an absolute path directly, bypassing the configured base.

Errors

Returns FerrayError::IoError if the file cannot be opened.

Trait Implementations

impl Clone for DataSource

fn clone(&self) -> DataSource

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for DataSource

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for DataSource

fn default() -> DataSource

Returns the “default value” for a type.