Some original headers are getting lost

[Mr0grog]

It looks like something has changed about either Requests or the Wayback Machine, and we are no longer including all the original archived headers in a Memento object’s headers property. For example:

from wayback import WaybackClient
c = WaybackClient()

memento = c.get_memento('https://robbrackett.com/', datetime='20220315020402')
memento.headers
# {'Content-Type': 'text/html'}

But the value of memento.headers should really be something like:

{'date': 'Tue, 15 Mar 2022 02:04:02 GMT', 'server': 'Apache', 'upgrade': 'h2,h2c', 'connection': 'Upgrade, Keep-Alive', 'last-modified': 'Mon, 30 Nov 2020 22:51:03 GMT', 'accept-ranges': 'bytes', 'content-length': '13182', 'vary': 'Accept-Encoding', 'keep-alive': 'timeout=15, max=768', 'Content-Type': 'text/html'}

(Based on https://web.archive.org/web/20220315020402id_/http://robbrackett.com/)

[Mr0grog]

At a quick glance, it looks like archive.org has started returning x-archive-orig-* headers with lower-case header names, and we are looking for capitalized ones (which they used to be):

wayback/wayback/_models.py

Lines 273 to 277 in bce65fd

	prefix = 'X-Archive-Orig-'
	headers = {
	key[len(prefix):]: value for key, value in raw_headers.items()
	if key.startswith(prefix)
	}

I’m guessing this started happening when they added HTTP/2 support (in HTTP/2, all header names are lower-case). That said, we can’t just switch to looking for lower-case here, since archive.org’s HTTP/1.1 responses still include upper-cased names for standard headers like Date and Location.