holoconf 0.4.0

Cross-language configuration library with resolver support

holoconf

A Python configuration library with hierarchical merging, interpolation, and schema validation. Built on a high-performance Rust core.

Installation

pip install holoconf

Quick Start

from holoconf import Config

# Load from YAML string
config = Config.loads("""
database:
  host: ${env:DB_HOST,localhost}
  port: 5432
  url: postgresql://${.host}:${.port}/mydb
""")

# Access values with type coercion
print(config.get("database.host"))      # Uses DB_HOST env var or "localhost"
print(config.get_int("database.port"))  # 5432
print(config.get("database.url"))       # Resolves self-references

# Load from file
config = Config.load("config.yaml")

# Merge multiple configs (later files override earlier)
config = Config.load("base.yaml", "override.yaml")

# Export resolved configuration
print(config.to_yaml())
print(config.to_json())

Features

• Environment variables: ${env:VAR} or ${env:VAR,default}
• Self-references: ${path.to.value} or ${.sibling} for relative paths
• File includes: ${file:./other.yaml}
• Type coercion: get_int(), get_bool(), get_float(), get_list(), get_dict()
• Lazy resolution: Values resolved on access, cached for efficiency
• Schema validation: Validate against JSON Schema
• Escape sequences: \${literal} for literal ${

Interpolation Syntax

Syntax	Description	Example
${env:VAR}	Environment variable	${env:HOME}
${env:VAR,default}	Env var with default	${env:PORT,8080}
${path.to.value}	Self-reference	${database.host}
${.sibling}	Relative reference	${.port}
${file:path}	Include file	${file:./secrets.yaml}
\${literal}	Escape (literal ${)	\${not_interpolated}

CLI

holoconf includes a command-line interface:

# Get a configuration value
holoconf get database.host --config config.yaml

# Dump resolved configuration
holoconf dump --config config.yaml --format json

Documentation

• User Guide - Full documentation
• API Reference - Python API docs
• GitHub - Source code and issues

License

Licensed under either of Apache License, Version 2.0 or MIT license at your option.