Enum CompressionWriter 

pub enum CompressionWriter {
    Plain(BufWriter<File>),
    Gzip(GzEncoder<File>),
    Zlib(ZlibEncoder<File>),
    Zstd(Encoder<'static, File>),
    Brotli(CompressorWriter<File>),
}

A writer that handles optional compression transparently.

Wraps different compression encoders behind a unified interface that implements Write and provides a finish() method for cleanup.

Example

use json_archive::compression_writer::CompressionWriter;
use json_archive::detection::CompressionFormat;
use std::io::Write;

let mut writer = CompressionWriter::create(path, CompressionFormat::Gzip)?;
writeln!(writer, "some data")?;
writer.finish()?;

Variants

Plain(BufWriter<File>)

Uncompressed output - uses BufWriter since File has no internal buffering

Gzip(GzEncoder<File>)

Compression encoders write directly to File - they do their own internal buffering

Zlib(ZlibEncoder<File>)

Zstd(Encoder<'static, File>)

Brotli(CompressorWriter<File>)

Implementations

impl CompressionWriter

pub fn create( path: &Path, format: CompressionFormat, ) -> Result<Self, Vec<Diagnostic>>

Open a file for writing with the specified compression format.

Errors

Returns a diagnostic explaining:

• What file we tried to create
• What compression format was requested
• Why it failed (permissions, disk full, unsupported format, etc.)

pub fn finish(self) -> Result<(), Vec<Diagnostic>>

Finish writing and flush all buffers.

For compressed formats, this finalizes the compression stream. Must be called before dropping to ensure all data is written.

Errors

Returns a diagnostic if flushing or finalizing fails.

Important: This method does not clean up the output file on error. If finish() fails, the caller is responsible for removing the partially-written file themselves:

if let Err(diagnostics) = writer.finish() {
    let _ = std::fs::remove_file(&path);
    return Err(diagnostics);
}

Trait Implementations

impl Write for CompressionWriter

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.