Why is $_SERVER[\'HTTP_REFERER\'] Empty in PHP?

Getting Referrer URL in PHP

The Problem

When retrieving the referrer URL using $_SERVER['HTTP_REFERER'], it remains empty.

Identifying the Missing Variable

The prompt includes a snippet of $_SERVER, revealing that the missing variable is HTTP_REFERER.

Reasons for Empty $_SERVER['HTTP_REFERER']

1. No Referrer: Users might navigate directly to the page without using a hyperlink or typing in the URL.
2. Disconnected Users: Those submitting requests programmatically (e.g., with CURL) need not specify a referrer.

What to Consider

In the context of the provided $_SERVER output, the HTTP_REFERER variable is indeed missing. However, it's important to note that the omission of specific values has been censored for privacy purposes, and the actual output may differ.

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