es-toolkit/dist/promise/mutex.js

A state-of-the-art, high-performance JavaScript utility library with a small bundle size and strong type annotations.

const require_semaphore = require("./semaphore.js");
//#region src/promise/mutex.ts
/**
* A Mutex (mutual exclusion lock) for async functions.
* It allows only one async task to access a critical section at a time.
*
* @example
* const mutex = new Mutex();
*
* async function criticalSection() {
*   await mutex.acquire();
*   try {
*     // This code section cannot be executed simultaneously
*   } finally {
*     mutex.release();
*   }
* }
*
* criticalSection();
* criticalSection(); // This call will wait until the first call releases the mutex.
*/
var Mutex = class {
	semaphore = new require_semaphore.Semaphore(1);
	/**
	* Checks if the mutex is currently locked.
	* @returns True if the mutex is locked, false otherwise.
	*
	* @example
	* const mutex = new Mutex();
	* console.log(mutex.isLocked); // false
	* await mutex.acquire();
	* console.log(mutex.isLocked); // true
	* mutex.release();
	* console.log(mutex.isLocked); // false
	*/
	get isLocked() {
		return this.semaphore.available === 0;
	}
	/**
	* Acquires the mutex, blocking if necessary until it is available.
	* @returns A promise that resolves when the mutex is acquired.
	*
	* @example
	* const mutex = new Mutex();
	* await mutex.acquire();
	* try {
	*   // This code section cannot be executed simultaneously
	* } finally {
	*   mutex.release();
	* }
	*/
	async acquire() {
		return this.semaphore.acquire();
	}
	/**
	* Releases the mutex, allowing another waiting task to proceed.
	*
	* @example
	* const mutex = new Mutex();
	* await mutex.acquire();
	* try {
	*   // This code section cannot be executed simultaneously
	* } finally {
	*   mutex.release(); // Allows another waiting task to proceed.
	* }
	*/
	release() {
		this.semaphore.release();
	}
};
//#endregion
exports.Mutex = Mutex;