hgweb.cgi

clonebundles: add support for inline (streaming) clonebundles

The idea behind inline clonebundles is to send them through
the ssh or https connection to the Mercurial server.
We've been using this specifically for streaming clonebundles,
although it works for 'regular' clonebundles as well
(but is less relevant, since pullbundles exist).

We've had this enabled for around 9 months for a part
of our users.

A few benefits are:
- no need to secure an external system,
  since everything goes through the same Mercurial server
- easier scaling (in our case: no risk of inconsistencies
  between multiple mercurial-server mirrors and nginx clonebundles hosts)

Remaining topics/questions right now:
- The inline clonebundles don't work for https yet.
  This is because httppeer doesn't seem to support sending client
  capabilities.
  I didn't focus on that as my main goal was to get this working
  for ssh.

#!/usr/bin/env python3
#
# An example hgweb CGI script, edit as necessary
# See also https://mercurial-scm.org/wiki/PublishingRepositories

# Path to repo or hgweb config to serve (see 'hg help hgweb')
config = b"/path/to/repo/or/config"

# Uncomment and adjust if Mercurial is not installed system-wide
# (consult "installed modules" path from 'hg debuginstall'):
# import sys; sys.path.insert(0, "/path/to/python/lib")

# Uncomment to send python tracebacks to the browser if an error occurs:
# import cgitb; cgitb.enable()

from mercurial import demandimport

demandimport.enable()
from mercurial.hgweb import hgweb, wsgicgi

application = hgweb(config)
wsgicgi.launch(application)