title: How to send data message without using Firebase console
body: <p>I am developing post and comment app, where one user can post some question, and any other use can answer on that post. but when any user comments on a post a user who post the question should receive notification. Suppose User (A) posted some question and User (B) answer on that. then user A should notify that somebody answers on your post and after clicking on a notification a particular post should open.
  Help me to sort the problem thankyou in advance :)</p>