async-await-mutex-lock

Mutex locks for async functions with functionality to use keys for separate locks

Without Key

import { Lock } from "async-await-mutex-lock";

let lock = new Lock();

async function serialTask() {
  await lock.acquire();

  try {
    // Don't return a promise here as Promise may resolve after finally
    // has executed
  } finally {
    lock.release();
  }
}

With Key

All the keys will have their own separate locks and separate waiting lists. A key can have any type (eg. string, number, etc. or a custom type allowed by typescript as a Map key)

import { Lock } from "async-await-mutex-lock";

let lock = new Lock<string>();

async function serialTask() {
  await lock.acquire("myKey");

  try {
    // Don't return a promise here as Promise may resolve after finally
    // has executed
  }
  finally {
    lock.release("myKey");
  }
}

async function serialTaskTwo() {
  await lock.acquire("myKeyTwo");

  try {
    // Don't return a promise here as Promise may resolve after finally
    // has executed
  }
  finally {
    lock.release("myKeyTwo");
  }
}

Checking if a lock is acquired or not

import { Lock } from "async-await-mutex-lock";

let lock = new Lock();

async function serialTask() {
  await lock.acquire();

  console.log(lock.isAcquired()); // prints true
}

isAcquired() with key checks for the given key separately.

import { Lock } from "async-await-mutex-lock";

let lock = new Lock<string>();

async function serialTask() {
  await lock.acquire("myKey");

  console.log(lock.isAcquired("myKey")) // prints true
}

Issues or Bugs

In case of any issues or bugs, please open a pull request here