Ask HN: Anybody knows a sentiment analysis API I can use in my web application?

I have built a web application where people write their pain points about specific products/ brands and services.

I want some sentiment analysis being done on the collected data to derive some important matrices.

Example for a post A

I want to know if

it is positive about the product neutral - merely suggestive negative overly negative super pissed off

Are there any ready-made tools available for this ? It need not be real time.