GTFS-Dense (.gtfsd)

GTFS-Dense is a fast, binary serialization format for static public transit data (GTFS).

The goal of GTFS-Dense is to enable quick, offline loading of an entire GTFS network on memory-constrained devices like mobile phones and web browsers, eliminating the need to parse large text files.

GTFS-Dense uses Protocol Buffers (PBF) as its underlying encoding format. A converter tool reads a standard GTFS feed, resolves all relational links (e.g., connecting a trip to its stop times and shape), and writes the data into a nested, graph-like structure.

Structure

• proto/ - The Protocol Buffers schema.
• src/gtfsdense/ - The main Python package.
  • converter.py - The script to convert GTFS to GTFS-Dense.
  • gtfs_dense_pb2.py - The generated Python code from the schema.
• gtfs-dense-rust/ - The Rust library for parsing GTFS-Dense.
• pyproject.toml - The Python project definition file.

Usage

To convert a GTFS .zip file to a .gtfsd file, use the converter script:

python -m src.gtfsdense.converter --input /path/to/your/gtfs.zip --output /path/to/your/output.gtfsd

Development

This project uses setuptools for packaging and protoc for generating the protobuf code.

Python

1. Install dependencies:

   pip install -e .

2. Modify the schema:

   Edit proto/gtfs-dense.proto.

3. Regenerate the protobuf code:

   protoc --python_out=src --proto_path=proto proto/gtfs-dense.proto

Rust

1. Build the library:

   cd gtfs-dense-rust
   cargo build

2. Run the example:

   cargo run --example print_feed -- <path/to/your.gtfsd>