Protecting PHP files from being called by other websites
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I have a website which fetches data from some PHP files to display it on the website. However, to protect my data to be used by other people, I wish to protect my PHP file being called by crawlers, bot etc to gather data.

I have prevented it by checking referral URL , but that can be easily by-passed. So, is there any other way to protect my data . I wish that only my website can call to those files.


Thanks !!