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🎲 KeyValues Storage

πŸ“š Summary ​

KeyValues Storage is a lightweight, file-based utility for managing key-value pairs using JSON. It offers intuitive methods for reading, writing, checking, and deleting values β€” all with support for both synchronous and asynchronous operations.

❓When Should You Use This Library? ​

You should consider using KeyValues Storage when you need:

  1. βœ… A simple and lightweight key-value store without the overhead of a full database.
  2. πŸ—‚οΈ To persist configuration or state in local .json files.
  3. πŸš€ Quick read/write operations for small or medium-sized data.
  4. 🧩 Nested object support with dot notation access ('user.profile.name').
  5. πŸ§ͺ Built-in support for both synchronous and asynchronous APIs.
  6. πŸ›‘οΈ Safe and atomic writes to prevent file corruption.
  7. πŸ“¦ Minimal dependencies (just lodash and write-file-atomic).

πŸ’‘ It's a great fit for: ​

  • Desktop apps (Electron, Tauri, etc.)
  • Low-traffic web servers or services
  • Caching user preferences
  • Storing app metadata
  • Configuration files
  • Testing and development tools
  • CLI Tools

πŸš€ Main Features ​

  • Manage key-value pairs in a persistent JSON file
  • Support for nested key paths
  • Multiple instances with different file names
  • Sync and async methods
  • Atomic writes and optional formatting

πŸ”§ Usage ​

⚠Install the library:

bash
npm install @heliomarpm/kvs
# or 
yarn add @heliomarpm/kvs

✏️ Example Code ​

js
// Default options
{
  atomicSave: true,
  fileName: 'keyvalues.json',
  prettify: false,
  numSpaces: 2
}
typescript
// Create a new instance of KeyValues with or without custom options
const kvs = new KeyValues()
//or 
const kvs = new KeyValues({ fileName: 'config.json',  prettify: true });

const color =
{
  "name": "cerulean",
  "code": {
    "hex": "#003BE6",
    "rgb": [0, 179, 230]
  }
}

// Set a key-value
kvs.setSync(['settings', 'language'], "pt-Br");
kvs.getSync(['settings', 'language'])	
// => 'pt-Br'

// Set/Add a key settings
kvs.setSync("settings.default", "en");
kvs.getSync("settings")
// => { "language": "pt-Br", "default": "en" }

kvs.getSync();	
// => { "settings": { "language": "pt-Br", "default": "en" } }

// replace key settings
kvs.setSync("settings", { theme: "dark"});
kvs.getSync("settings")
// => { "theme": "dark" }

// Added a new key-value
kvs.setSync("color", color);
kvs.getSync();
// => { "theme": "dark", "color": { "name": "cerulean", "code": { "rgb": [0, 179, 230], "hex": "#003BE6" } } }

// Replace all key-values
kvs.setSync(color);
kvs.getSync();
// => { "name": "cerulean", "code": { "rgb": [0, 179, 230], "hex": "#003BE6" } }

// Unset a key-value
kvs.unsetSync();
kvs.getSync();
// => {}

// Set a new key-values
kvs.setSync("color", color);
kvs.getSync();	
// => { "color": { "name": "cerulean", "code": { "rgb": [0, 179, 230], "hex": "#003BE6" } } }

kvs.getSync("color.name")
// => "cerulean"

kvs.getSync("color.code.hex")
// => "#003BE6"

kvs.getSync(["color", "code"])
// or
kvs.getSync("color.code")
// => { "hex": "#003BE6", "rgb": [0, 179, 230] }

kvs.getSync(["color", "hue"])
// => undefined

// Set a key-value pair
await kvs.set("color.name", "sapphire");

// Get the value at a specific key path
const value = await kvs.get("color.name");
// => "sapphire"

// Check if a key path exists
const exists = await kvs.has("color.name");
// => true

// Remove a key-value pair
await kvs.unset("color.name");
await kvs.get(); 
// => { "code": { "rgb": [0, 179, 230], "hex": "#003BE6" } }

const exists = kvs.hasSync("color.name");
// => false

kvs.unset().then(() => {
  console.log("All key-value pairs have been removed.");
});

πŸ“š API Reference ​

See the API documentation for a complete list of available functions and their signatures.

πŸ§ͺ Methods ​

MethodDescription
constructor(options?)Initializes a new instance of the KeyValues class with optional custom options.
file(): stringReturns the path to the JSON file.
reset(): voidResets the configuration of the KeyValues instance to default options.
has(keyPath): Promise<boolean>Checks if a key path exists asynchronously.
hasSync(keyPath): booleanChecks if a key path exists synchronously.
get<T>(keyPath?): Promise<T>Gets the value at a specific key path asynchronously.
getSync<T>(keyPath?): TGets the value at a specific key path synchronously.
set<T>(...args): Promise<void>Sets a value at a specific key path asynchronously.
setSync<T>(...args): voidSets a value at a specific key path synchronously.
unset(keyPath?): Promise<void>Removes a key-value pair at a specific key path asynchronously.
unsetSync(keyPath?): voidRemoves a key-value pair at a specific key path synchronously.

πŸ“¦ Project Scripts ​

  • npm run check β€” runs formatter, linter and import sorting to the requested files
  • npm run format β€” run the formatter on a set of files
  • npm run lint β€” run various checks on a set of files
  • npm run test β€” run unit tests
  • npm run test:c β€” run unit tests with coverage
  • npm run commit - run conventional commits check
  • npm run release:test β€” dry run semantic release
  • npm run build β€” build library

πŸ“¦ Dependencies ​

  • lodash Utility functions for working with objects and arrays.
  • write-file-atomic Ensures file writes are safe and atomic.

🀝 Contributing ​

We welcome contributions! Please read:

Thank you to everyone who has already contributed to the project!

Made with contrib.rocks. ​

❀️ Support this project ​

If this project helped you in any way, there are several ways to contribute.
Help us maintain and improve this template:

⭐ Starring the repository
🐞 Reporting bugs
πŸ’‘ Suggest features
🧾 Improving the documentation
πŸ“’ Share with others

πŸ’΅ Supporting via GitHub Sponsors, Ko-fi, Paypal or Liberapay, you decide. πŸ˜‰

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πŸ“ License ​

MIT Β© Heliomar P. Marques πŸ”