Comment by jbaudanza

The problem with resolving promises inside of `componentDidMount` is that there is no way to cancel those promises. If the component is unmounted, and then setState is called, it will generate an error (or a warning. I can't remember).

Facebook discusses this on its blog: https://reactjs.org/blog/2015/12/16/ismounted-antipattern.ht...

I've been using Observables which, in my experience, bind a little cleaner than Promises to React components.