Instructions

The package name is mojo-parquet. The Mojo import is parquet. The code generator command is gld-parquetgen-mojo.

Develop from this repository

Mojo is pinned to 1.1.0. Pixi installs it from the Modular channel. If that channel returns 401, put PREFIX_API_KEY in a local .env file and run the setup script again. Do not commit .env.

git clone https://github.com/leo-gan/gld-parquet.git
cd gld-parquet
bash scripts/ci-setup.sh
pixi run test

pixi run test compiles every file in tests/. pixi run check-generated regenerates tests/generated/ and diffs it. pixi run precompile writes .mojoc packages under /tmp/mojo-parquet-pkg.

Published package

The linux-64 package is on the prefix.dev channel leo-gan/leo-gan.

pixi add --channel https://prefix.dev/leo-gan/leo-gan mojo-parquet

That install provides parquet.mojoc and gld-parquetgen-mojo. It needs mojo-compiler 1.1.

Generate a struct

testdata/schema/record.json is a JSON Schema object. x-parquet-type selects the Parquet logical type when the JSON type is not enough. The title field names the generated struct.

pixi run mojo run -I src src/codegen/cli.mojo -- \
  --schema testdata/schema/record.json --out tests/generated

The struct Record has encoded_len, encode_to, and decode_from. encode_bytes returns one Parquet file that holds a single row.