Difference between return and return await in JavaScript

You might be thinking that these two approaches are the same. But there is a crucial difference between return and return await.

When we deal with promises, such as database queries, we commonly use await. For example:

async function getUserById(userId) {
  const user = await userRepository.findById(userId);
  return user;
}

However, in this case, it is not strictly necessary to use await. We can write it like this:

function getUserById(userId) {
  return userRepository.findById(userId);
}

Both options will work normally.

When we have a try/catch block, the behavior is different, and if you're unaware of this, it can cause unexpected errors.

function getUserById(userId) {
  try {
    return userRepository.findById(userId);
  } catch (error) {
    console.error(error.message);
  }
}

If an error occurs in findById, it won't be caught, and this will likely become a problem. This is where we need to use return await.

async function getUserById(userId) {
  try {
    return await userRepository.findById(userId);
  } catch (error) {
    console.error(error.message);
  }
}

Now, we are safe, and any error will fall into the catch block.

In summary, if we need to handle and process errors in a catch block, we must use return await to ensure the application operates correctly.

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