LANGUAGE » JAVASCRIPT » NODEJS

Built-in

Process

VariableDescription
process.envA object containing the user environment.
process.exitCodeExit code used when the script ends.
MethodDescription
process.exitImmediately terminates the process with the specified exit code.

Async

Creating an async function (returns Promise) and waiting for the result:

js
async function getUser() {}
const user = await getUser();

To continue the program meanwhile, use a callback:

js
getUser().then((user) => {});

Exit Code

If exiting the program due to an error, setting process.exitCode = 1 is preferred over process.exit(1) because it will wait for asynchronous code to finish, like writes to stdout. But you'll have to skip the remaining code if there is any:

js
if (somethingBadHappened()) {
  printStuff();
  process.exitCode = 1;
}

if (process.exitCode !== undefined) {
  // ...
}

Usually it is much easier to just raise an error that will not be catched for the same result:

js
if (somethingBadHappened()) {
  printStuff();
  throw new Error('Something bad happened');
}