README.md

Parkitect Blueprint Reader

Python API and CLI tool to read Parkitect's blueprints metadata.

PyPI - Documentation - Source code - Issue tracker - Changelog

Prerequisites

• Python >= 3.10

Installation

From PyPi

pip install parkitect-blueprint-reader

Locally

After cloning/downloading the repo:

pip install .

Usage

API

The API consists of one load() method, which reads blueprint metadata from the given binary file-like object and returns the parsed data as a dictionary.

import parkitect_blueprint_reader
from pprint import pprint

try:
    with open('coaster.png', 'rb') as fp: # Note it's opened in binary mode
        pprint(
            parkitect_blueprint_reader.load(fp)
        )
except Exception as e:
    print(e)

CLI

The CLI reads metadata from the given blueprint filename, then writes the parsed data as a JSON to stdout.

parkitect-blueprint-reader coaster.png

The --pretty option may be used to pretty-print the outputted JSON.

Data format

Data is stored in blueprints as follows, using the least significant bits steganography technique (described in the reference documents below):

• A three-bytes magic number: SM\x01 (Parkitect's main developer initials)
• Size (little-endian unsigned int), in bytes, of the gzippped content to be read
• A 16-bytes MD5 checksum
• The actual gzippped data, which is Size bytes long

References

• Parkitect devlog - Update 58
• Reddit - How are blueprints stored?
• GitHub - Parkitect Blueprint Investigation

Development

Getting source code and installing the package with dev dependencies

1. Clone the repository
2. From the root directory, run: pip install -e ".[dev]"

Releasing the package

From the root directory, run python setup.py upload. This will build the package, create a git tag and publish on PyPI.

__version__ in parkitect_blueprint_reader/__version__.py must be updated beforehand. It should adhere to Semantic Versioning.

An associated GitHub release must be created following the Keep a Changelog format.