Simple Distributed Lock with Mongo

lock.js

async function acquireLock(name) {
  // Open connection to database
  const collection = await db.collection('locks');

  try {
    // Insert an entry to the database, using the _id field, which already has a unique key constraint
    await collection.insertOne({ _id: name });

    // No exception was thrown, so we successfully acquired a lock
    return true;
  } catch (ex) {
    // 11000 means duplicate key error, which is expected on an active lock
    if (ex.code !== 11000) {
      // Uh-Oh, this is not an exception error
      throw ex;
    }

    return false;
  }
}

async function acquireAndExecute(name, fn) {
    const locked = await acquireLock(name);
    if (!locked) {
       // Lock could not be acquired
      return;
    }
  
    await fn();
}