Enforce file upload size on Heroku?

Question

Got a Rails app on Heroku. I want to limit the size of a file upload if possible. The file is processed as a StringIO object, so the file contents will be processed in mem

Answer 1

You could run NGINX in front of your app server to enforce this constraint.

This is fairly simple with heroku, you will need a nginx.conf and this buildpack.

# nginx.conf
http {
    #...
    client_max_body_size 100m;
    #...
}

Note: But be aware that on heroku, NGINX run inside your dynos (ie. local to each instance).

https://blog.codeship.com/how-to-deploy-nginx-on-heroku

Hope that's help!