Prevent access a file in public folder

I have a json file inside a public folder. I want to restrict the access to the json file from browser but it can be accessed from controller. I do not know how to do it.
For example, json file is placed inside key/foo folder which inside public folder → public/key/foo/bar.json.
I created .htaccess (Deny from all) file in key folder but I still can access bar.json from the browser with this url path http://localhost/key/foo/bar.json

Any help?

Thank you.

First, why would you store a secret file in a 'public' folder to restrict access?
Does it contain configurations about something that should be secret?

Please read:

php net - chmod

I would store something like this in an database encrypted.

What did you Try? What did you Get? What did you Expect?

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