Flask + nginx + uWSGI 问题：为什么 Location 头被修改为完整 URL？🤔

Hey folks! 👋 I'm stuck with this weird Flask header issue and could really use some help debugging this.

So here's the deal - I've got a Flask app running behind nginx with uWSGI, and the Location header is playing tricks on me 😅. I'm trying to figure out where the full URL is getting added to the response.

Here's what I tried first:

# Just slapped this after_request hook to peek at headers
@app.after_request
def add_header(response):
    print(response.headers)  # Debugging 101, amirite?
    return response

In my uWSGI logs, I see the simple version:

Location: /

But when I check the actual packet capture between uWSGI and nginx, suddenly it's got the full URL:

Location: http://<full-url>/

What gives? 🤔 I thought Flask was setting this, but clearly something else is modifying it after Flask's response.

Things I've checked:

1. Flask's redirect() function - nope, not the culprit
2. Nginx config for proxy settings - looks normal
3. uWSGI transformation - not seeing anything obvious

This is driving me nuts because I need to ensure the Location header is correct for some auth callbacks. The inconsistency is breaking my flow!

Anyone run into this before? Is nginx doing some magic here that I'm missing? Or maybe uWSGI is being too helpful?

PS: Bonus points if you can explain why my hex dump skills are suddenly useful in web dev 😂