Environment variable is not assigning with Typescript

Question

My code is:

const port: Number = process.env.PORT || 3000;

[ts]
Type 'string | 3000' is not assignable to type 'Number'.
  Type 'string' is not assignable to type 'Number'.

I tried

const port: Number = parseInt(process.env.PORT, 10) || 3000;

But it gives me another error:

Argument of type 'string | undefined' is not assignable to parameter of type 'string'.
  Type 'undefined' is not assignable to type 'string'.
(property) NodeJS.Process.env: NodeJS.ProcessEnv

What am I doing wrong?

Answer 1

const port: Number = parseInt(<string>process.env.PORT, 10) || 3000

This solved it. I think it's called Type Assertion