Struct re_sdk::external::arrow2::io::ipc::write::FileWriter

pub struct FileWriter<W>
where
    W: Write,
{
    pub(crate) writer: W,
    pub(crate) options: WriteOptions,
    pub(crate) schema: Schema,
    pub(crate) ipc_fields: Vec<IpcField>,
    pub(crate) block_offsets: usize,
    pub(crate) dictionary_blocks: Vec<Block>,
    pub(crate) record_blocks: Vec<Block>,
    pub(crate) state: State,
    pub(crate) dictionary_tracker: DictionaryTracker,
    pub(crate) encoded_message: EncodedData,
}

Arrow file writer

Fields

writer: W

options: WriteOptions

schema: Schema

ipc_fields: Vec<IpcField>

block_offsets: usize

dictionary_blocks: Vec<Block>

record_blocks: Vec<Block>

state: State

dictionary_tracker: DictionaryTracker

encoded_message: EncodedData

Implementations

impl<R> FileWriter<R>

where R: Read + Seek + Write,

pub fn try_from_file( writer: R, metadata: FileMetadata, options: WriteOptions ) -> Result<FileWriter<R>, Error>

Creates a new FileWriter from an existing file, seeking to the last message and appending new messages afterwards. Users call finish to write the footer (with both) the existing and appended messages on it.

Error

This function errors iff:

• the file’s endianess is not the native endianess (not yet supported)
• the file is not a valid Arrow IPC file

impl<W> FileWriter<W>

where W: Write,

pub fn try_new( writer: W, schema: Schema, ipc_fields: Option<Vec<IpcField>>, options: WriteOptions ) -> Result<FileWriter<W>, Error>

Creates a new FileWriter and writes the header to writer

pub fn new( writer: W, schema: Schema, ipc_fields: Option<Vec<IpcField>>, options: WriteOptions ) -> FileWriter<W>

Creates a new FileWriter.

pub fn into_inner(self) -> W

Consumes itself into the inner writer

pub fn get_scratches(&mut self) -> EncodedData

Get the inner memory scratches so they can be reused in a new writer. This can be utilized to save memory allocations for performance reasons.

pub fn set_scratches(&mut self, scratches: EncodedData)

Set the inner memory scratches so they can be reused in a new writer. This can be utilized to save memory allocations for performance reasons.

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

Writes the header and first (schema) message to the file.

Errors

Errors if the file has been started or has finished.

pub fn write( &mut self, chunk: &Chunk<Box<dyn Array>>, ipc_fields: Option<&[IpcField]> ) -> Result<(), Error>

Writes Chunk to the file

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

Write footer and closing tag, then mark the writer as done