url: add distribution and version to user-agent request header (BC)
As a server operator, I've always wanted to know what Mercurial
version clients are running so I can track version adoption and
make informed decisions about which versions of Mercurial to
support in extensions. Unfortunately, there is no easy way to discern
this today: the best you can do is look for high-level feature usage
(e.g. bundle2) or sniff capabilities from bundle2 commands. And these
things aren't changed frequently enough to tell you anything that
interesting.
Nearly every piece of software talking HTTP sends its version in
the user agent. This includes web browsers, curl, and even Git.
This patch adds the distribution name and version to the user-agent
HTTP request header. We choose "Mercurial" for the distribution
name because that seems appropriate. The version string comes
from __version__.
The value is inside parenthesis for a few reasons:
* The version *may* contain spaces
* Alternate forms like "Mercurial/<version>" imply structure and
since the user agent should not be used by servers for protocol
or feature negotiation/detection, we don't want to even give the
illusion that the value should be parsed. A free form field is
the most hostile to parsing.
Flagging the patch as BC so it shows up in release notes. This
change should be backwards compatible. But I wouldn't be surprised if
a server somewhere is filtering on the exact old user agent string. So
I want to make noise about this change.
# node.py - basic nodeid manipulation for mercurial
#
# Copyright 2005, 2006 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
from __future__ import absolute_import
import binascii
# This ugly style has a noticeable effect in manifest parsing
hex = binascii.hexlify
bin = binascii.unhexlify
nullrev = -1
nullid = b"\0" * 20
nullhex = hex(nullid)
# pseudo identifiers for working directory
# (they are experimental, so don't add too many dependencies on them)
wdirrev = 0x7fffffff
wdirid = b"\xff" * 20
def short(node):
return hex(node[:6])