node-config/node-config
Node Config
This is a configuration manager for Node.js applications that handles hierarchical settings across different deployment environments. It functions as an environment-based loader and settings parser that merges default configurations with overrides based on the current runtime context and hostname.
The project distinguishes itself through a priority-based merge strategy that incorporates environment variables, command-line arguments, and external data sources to supersede file-based settings. It supports multi-format parsing for JSON, YAML, JavaScript, and TypeScript files, and allows for custom parsing modules to define how specific file extensions are processed.
The system provides extensive object management utilities, including recursive object freezing to enforce immutability and deep object cloning. It also features asynchronous settings resolution and deferred value evaluation, where specific settings are calculated after all overrides have been merged.
The library includes specialized capabilities for client-side configuration injection during build time and provides fail-fast retrieval mechanisms to throw exceptions when required keys are missing.
Features
- Node.js Application Configurations - Provides a comprehensive hierarchical configuration manager specifically tailored for Node.js applications.
- Hierarchical Configuration Frameworks - Manages hierarchical settings across different deployment environments using multiple file formats and environment variables.
- Command Line Configuration - Supports injecting JSON-formatted configuration overrides via command-line arguments or environment variables.
- Environment Variable Mapping - Binds system environment variables to configuration keys with support for boolean and numeric type casting.
- Multi-Format Support - Parses settings from various formats including JSON, YAML, JS, and TS while automatically stripping comments.
- Environment-Specific Configuration Overrides - Organizes default settings and environment-specific overrides to ensure consistent behavior across different deployment stages.
- Configuration Merging - Loads and merges hierarchical configuration files based on the current deployment environment and hostname.
- Multi-Format Configuration Loading - Reads settings from multiple directories using various formats including JSON, JS, TS, and CommonJS modules.
- Environment-Specific Loading - Loads different configuration files based on the current runtime environment and hostname.
- Environment Variable-Based Configuration - Fetches configuration-related environment variables, incorporating applicable defaults and overrides into the application settings.
- Configuration Managers - Implements a full-featured manager for hierarchical application settings across multiple environments and file formats.
- Application Parameter Configurators - Defines default parameters and extends them for different deployment environments to maintain a consistent interface.
- Hierarchical Configuration Overrides - Applies settings across tiered levels where deployment-specific overrides supersede general defaults.
- Value Resolution Strategies - Implements logic to retrieve specific settings by key and validate their existence to ensure application stability.
- Hierarchical Configuration Overrides - Manages nested configuration objects using a priority-based merge strategy for hierarchical overrides.
- Immutability Enforcement Utilities - Enforces read-only access to application settings by freezing configuration objects to prevent accidental runtime mutations.
- Object Freezing - Uses recursive object freezing to ensure that configuration settings remain immutable during application runtime.
- Priority-Based Configuration Merging - Merges configuration files based on a priority order where deployment-specific settings override host-specific ones.
- Recursive Configuration Merging - Combines default settings and environment overrides into a single object using deep recursive merging.
- Pluggable Format Deserializers - Allows external modules to define custom parsing logic for different configuration file extensions.
- Client-Side Configuration Injection - Injects environment-specific settings into client-side bundles during build time via global variables or static files.
- Client-side Environment Variables - Injects environment-specific settings into client-side bundles during the build process via global variables.
- Configuration Parsers - Parses configuration data from multiple formats including JSON, YAML, JavaScript, and TypeScript files.
- External Configuration Integration - Integrates application parameters with external configuration sources, environment variables, and command-line arguments.
- Configuration Retrieval - Implements fail-fast retrieval to ensure the application does not start with missing required configuration keys.
- Configuration Variable Overrides - Uses external data sources to override default file-based settings.
- Runtime Environment Variable Injections - Injects application configuration changes at runtime using JSON strings passed through shell variables.
- Custom Configuration Parsers - Allows the specification of external modules to customize how configuration files are read and parsed.
- Module Configuration Overrides - Merges default module settings with global configurations to allow users to override specific module parameters.
- Object Merging - Implements recursive object merging to combine multiple configuration sources into a single nested structure.
- Configuration Key Binding - Links flat environment variable names to specific configuration keys using a mapping file.
- Asynchronous Configuration Resolution - Processes asynchronous functions and promises within configuration files to ensure all values are loaded before startup.
- Deferred Value Evaluation - Supports calculating configuration values using functions that execute after all environment-specific overrides are merged.
- Deferred Configuration Values - Provides the ability to define configuration values as functions that execute after all environment overrides are merged.
- Strict Configuration Modes - Enforces strict validation at startup by throwing exceptions if required environment or instance configuration files are missing.
