Is there a way to delete robots.txt file using heroku deploy hook?

I have one repo that pushes to different domains (environments). I want to run a script that alters a file (robots.txt) based on the environment it is run in.

The language of the app is javascript on Ember.

Is there a way I can do this using Heroku? I looked at slug compilation and deploy hooks, but it doesn't look like this functionality exists with these methods.

Ways I can think of doing this are:

1. 
   

   some sort of pre-deploy hook, where I would add a robots-production.txt robots-staging.txt and rename the proper environment file to robots.txt on deploy.

   
   


2. 
   

   Dynamically altering the robots.txt using javascript based on the environment at runtime.

   
   

Thoughts?