go-zlib

Let's you use zlib in Go. Direct fully-featured API bindings to zlib.

It improves on the current standard libraries zlib and deflate by supporting all the possible options for zlib.

Easy to use Writer and Reader interfaces in addition to direct and memory-safe access to zlib low-level methods.

Why another zlib library in Go?

At the time of writing (Dec 2023), these are the montivations to write this library:

Hidden configurations: The standard libraries zlib and deflate hide most of the configurations of the underlying compression algorithm. A library like 4kills/go-zlib exposes some of those configurations like compression strategies and compression levels but still hides other parameters like WindowBits and MemoryLevel. This library exposes all these configurations in addition to giving more control on memory consumption via the BufferSize parameter.
Limited IO interfaces: The prevously mentioned libraries implement Writer interface for compression and Reader interface for decompression. However, there are cases where a compression reader or a decompression writer are needed. This library supports both interfaces for both compression and decompression.
Access to lower level APIs: The previously mentioned libraries only support Reader and Writer interfaces. In addition to supporting these interfaces, this library gives access to compressor and decompressor via FeederConsumer interface which allows incremental feeding of data and consumption of results. In addition to that, it gives direct access to zlib zstream and its methods.

Installation

go get github.com/MeenaAlfons/go-zlib

Prerequisites

This library assumes that zlib is already installed and its include and library files are accessable to build tools.

Many operating systems come with zlib already installed. If you need to install zlib, here is a list of commands to help:

macos: brew install zlib
debian: apt install zlib
alpine: apk add zlib
windows: download binary here

Usage

Compression and decompression can be plugged into any pipeline via Writer and Reader interfaces. Compression and decompression are supported on both writing and reading sides. Here are the possilities:

NewCompressReader
NewCompressWriter
NewDecompressReader
NewDecompressWriter

Many examples can be found in examples directory. Here is one example:

data := []byte("Hello World!")
r := bytes.NewReader(data)

opts := common.DefaultCompressOptions()
compressorReader, err := zlib.NewCompressReader(r, opts)
if err != nil {
    // Error creating compressor reader
}

compressedData, err := io.ReadAll(compressorReader)
if err != nil {
    // Error reading from compressor reader
}
return compressedData

Development

Run tests

go test ./...

Run tests with debug logs

go test ./... -tags debug

License

MIT License

Acknowledgments

zlib is written in C by Jean-loup Gailly and Mark Adler.