Struct polars::export::arrow::io::ipc::write::StreamWriter

pub struct StreamWriter<W> where
    W: Write,  { /* private fields */ }

This is supported on crate feature io_ipc only.

Arrow stream writer

The data written by this writer must be read in order. To signal that no more data is arriving through the stream call self.finish();

For a usage walkthrough consult this example.

Implementations

impl<W> StreamWriter<W> where
    W: Write, 

pub fn new(writer: W, write_options: WriteOptions) -> StreamWriter<W>

Creates a new StreamWriter

pub fn start(
    &mut self,
    schema: &Schema,
    ipc_fields: Option<Vec<IpcField, Global>>
) -> Result<(), ArrowError>

Starts the stream by writing a Schema message to it. Use ipc_fields to declare dictionary ids in the schema, for dictionary-reuse

pub fn write(
    &mut self,
    columns: &Chunk<Arc<dyn Array + 'static>>,
    ipc_fields: Option<&[IpcField]>
) -> Result<(), ArrowError>

Writes Chunk to the stream

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

Write continuation bytes, and mark the stream as done

pub fn into_inner(self) -> W

Consumes itself, returning the inner writer.