tiny_flags

A lightweight Python package for efficient settings management using bitfields. Handle language preferences, feature flags, and other configurations using a single 32 or 64-bit integer.

Features

• 32-bit and 64-bit bitfield support
• Automatic bit position management
• Boolean flags and multi-option settings
• Ordered dictionary configuration
• Zero runtime dependencies
• Type-checked with mypy strict mode

Installation

pip install tiny_flags

Quick Start

from collections import OrderedDict
from tiny_flags import TinyFlags

# Define your settings
fields = OrderedDict([
    ('language', ['english', 'spanish', 'french']),  # Uses 2 bits
    ('dark_mode', False),                            # Uses 1 bit
    ('notifications', True)                          # Uses 1 bit
])

# Initialize (default 32-bit, pass bits64=True for 64-bit)
manager = TinyFlags(fields)

# Set values
manager.set_value('language', 'spanish')
manager.set_value('dark_mode', True)

# Get values
manager.get_value('language')        # 'spanish'
manager.get_value('dark_mode')       # True
manager.get_value('notifications')   # True

# Persist the entire state as a single integer
state = manager.bitfield.value       # e.g. 13

# Restore from that integer later
new_manager = TinyFlags(fields)
new_manager.bitfield.value = state
new_manager.get_value('language')    # 'spanish'

How Bit Widths Work

Option lists must have at least 2 items. Bit allocation is always based on powers of 2, so odd-count lists leave unused slots. Consider reserving those for future options.

Design Considerations

Order matters. The OrderedDict key order determines bit positions. Changing the order after data is persisted will corrupt stored values. When evolving your schema:

• Add new fields at the end
• Don't remove fields — rename unused ones with a _ prefix and ignore them

Database storage. The bitfield value is a single integer, making it efficient to store. However, you cannot query individual flags with database indexes — the index covers the whole integer. If you need complex queries on specific flags, store those as separate columns.

32 vs 64-bit. Default is 32-bit (up to 32 flags/option bits). Pass bits64=True for 64-bit support. Ensure your storage layer supports 64-bit integers before using this mode.

Development

git clone https://github.com/FistOfTheNorthStar/tiny_flags
cd tiny_flags
pip install -e ".[dev]"

Run checks

pytest --cov=tiny_flags           # tests + coverage
ruff check src/ tests/            # linting
mypy src/                         # type checking

Contributions are welcome.

License

Distributed under the MIT License. See LICENSE for more information.