Struct DatasetWriter 

pub struct DatasetWriter { /* private fields */ }

Wrapper for easier Dataset generation

This type can be used to write data to a file and then automatically generate an id and calculate a hash for the file. The hash algorithm used is SHA-512 (see also Dataset::from_file).

This type implements Write and Seek and therefor can be used together with things like serde_json::to_writer or similar functions.

Example

let mut writer = DatasetWriter::new("output/data")?;
serde_json::to_writer(&mut writer, &[0, 1, 2])?;
let dataset = writer.finalize(())?;
dbsession.add_dataset(&dataset)?;

Implementations

impl DatasetWriter

pub fn new<P: AsRef<Path>>(folder: P) -> Result<Self, Error>

Create new writer

This generates an id uses this as a filename to create a file in folder. If the path did not exist before, parent folders are created.

pub fn finalize<S: Serialize + Debug>( self, metadata: S, ) -> Result<Dataset, Error>

Generate Dataset

This uses Dataset::from_file to calculate a SHA-512 hash and generate a Dataset.

Arguments

• metadata: associated metadata, has to serializable to a Map

pub fn finalize_with_host<S: Serialize + Debug>( self, metadata: S, host: Option<Host>, ) -> Result<Dataset, Error>

Generate Dataset

This uses Dataset::from_file to calculate a SHA-512 hash and generate a Dataset.

Arguments

• metadata: associated metadata, has to serializable to a Map

Trait Implementations

impl Seek for DatasetWriter

Available on crate feature sha only.

fn seek(&mut self, pos: SeekFrom) -> Result<u64>

Seek to an offset, in bytes, in a stream.

fn rewind(&mut self) -> Result<(), Error>

Rewind to the beginning of a stream.

fn stream_len(&mut self) -> Result<u64, Error>

🔬This is a nightly-only experimental API. (seek_stream_len)

Returns the length of this stream (in bytes).

fn stream_position(&mut self) -> Result<u64, Error>

Returns the current seek position from the start of the stream.

fn seek_relative(&mut self, offset: i64) -> Result<(), Error>

Seeks relative to the current position.

impl Write for DatasetWriter

Available on crate feature sha only.

fn write(&mut self, buf: &[u8]) -> Result<usize>

Writes a buffer into this writer, returning how many bytes were written.

fn flush(&mut self) -> Result<()>

Flushes this output stream, ensuring that all intermediately buffered contents reach their destination.

fn write_vectored(&mut self, bufs: &[IoSlice<'_>]) -> Result<usize, Error>

Like write, except that it writes from a slice of buffers.

fn is_write_vectored(&self) -> bool

🔬This is a nightly-only experimental API. (can_vector)

Determines if this Writer has an efficient write_vectored implementation.

fn write_all(&mut self, buf: &[u8]) -> Result<(), Error>

Attempts to write an entire buffer into this writer.

fn write_all_vectored(&mut self, bufs: &mut [IoSlice<'_>]) -> Result<(), Error>

🔬This is a nightly-only experimental API. (write_all_vectored)

Attempts to write multiple buffers into this writer.

fn write_fmt(&mut self, args: Arguments<'_>) -> Result<(), Error>

Writes a formatted string into this writer, returning any error encountered.

fn by_ref(&mut self) -> &mut Self

where Self: Sized,

Creates a “by reference” adapter for this instance of Write.