[Apache Parquet](https://parquet.apache.org) is a popular columnar storage format that is widely used in data engineering, data science, and machine learning applications for efficiently storing and processing large datasets. It supports a number of different compression formats, but most parquet files use snappy compression.
[Hyparquet](https://github.com/hyparam/hyparquet) is a fast and lightweight parquet reader that is designed to work in both node.js and the browser.
By default, hyparquet only supports `uncompressed` and `snappy` compressed files (the most common parquet compression codecs). The `hyparquet-compressors` package extends support for all legal parquet compression formats.
`hyparquet-compressors` works in both node.js and the browser. Uses js and wasm packages, no system dependencies.
Snappy compression uses [hysnappy](https://github.com/hyparam/hysnappy) for fast snappy decompression using a minimal [WASM](https://en.wikipedia.org/wiki/WebAssembly) module.
We load the wasm module _synchronously_ from base64 in the js file. This avoids a network request, and greatly simplifies bundling and serving wasm.
Includes modifications to handle repeated back-to-back gzip streams that sometimes occur in parquet files (but are not supported by fflate).
For gzip, the `output` buffer argument is optional:
- If `output` is defined, the decompressor will write to `output` until it is full.
- If `output` is undefined, the decompressor will allocate a new buffer, and expand it as needed to fit the uncompressed gzip data. Importantly, the caller should use the _returned_ buffer.
