view hgext/schemes.py @ 25602:85fb416f2fa7

hgweb: provide symrev (symbolic revision) property to the templates

One of the features of hgweb is that current position in repo history is
remembered between separate requests. That is, links from /rev/<node_hash> lead
to /file/<node_hash> or /log/<node_hash>, so it's easy to dig deep into the
history. However, such links could only use node hashes and local revision
numbers, so while staying at one exact revision is easy, staying on top of the
changes is not, because hashes presumably can't change (local revision numbers
can, but probably not in a way you'd find useful for navigating).

So while you could use 'tip' or 'default' in a url, links on that page would be
permanent. This is not always desired (think /rev/tip or /graph/stable or
/log/@) and is sometimes just confusing (i.e. /log/<not the tip hash>, when
recent history is not displayed). And if user changed url deliberately to say
default instead of <some node hash>, the page ignores that fact and uses node
hash in its links, which means that navigation is, in a way, broken.

This new property, symrev, is used for storing current revision the way it was
specified, so then templates can use it in links and thus "not dereference" the
symbolic revision. It is an additional way to produce links, so not every link
needs to drop {node|short} in favor of {symrev}, many will still use node hash
(log and filelog entries, annotate lines, etc).

Some pages (e.g. summary, tags) always use the tip changeset for their context,
in such cases symrev is set to 'tip'. This is needed in case the pages want to
provide archive links.

highlight extension needs to be updated, since _filerevision now takes an
additional positional argument (signature "web, req, tmpl" is used by most of
webcommands.py functions).

More references to symbolic revisions and related gripes: issue2296, issue2826,
issue3594, issue3634.

# Copyright 2009, Alexander Solovyov <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

"""extend schemes with shortcuts to repository swarms

This extension allows you to specify shortcuts for parent URLs with a
lot of repositories to act like a scheme, for example::

  [schemes]
  py = http://code.python.org/hg/

After that you can use it like::

  hg clone py://trunk/

Additionally there is support for some more complex schemas, for
example used by Google Code::

  [schemes]
  gcode = http://{1}.googlecode.com/hg/

The syntax is taken from Mercurial templates, and you have unlimited
number of variables, starting with ``{1}`` and continuing with
``{2}``, ``{3}`` and so on. This variables will receive parts of URL
supplied, split by ``/``. Anything not specified as ``{part}`` will be
just appended to an URL.

For convenience, the extension adds these schemes by default::

  [schemes]
  py = http://hg.python.org/
  bb = https://bitbucket.org/
  bb+ssh = ssh://[e-mail]/
  gcode = https://{1}.googlecode.com/hg/
  kiln = https://{1}.kilnhg.com/Repo/

You can override a predefined scheme by defining a new scheme with the
same name.
"""

import os, re
from mercurial import extensions, hg, templater, util
from mercurial.i18n import _

# Note for extension authors: ONLY specify testedwith = 'internal' for
# extensions which SHIP WITH MERCURIAL. Non-mainline extensions should
# be specifying the version(s) of Mercurial they are tested with, or
# leave the attribute unspecified.
testedwith = 'internal'


class ShortRepository(object):
    def __init__(self, url, scheme, templater):
        self.scheme = scheme
        self.templater = templater
        self.url = url
        try:
            self.parts = max(map(int, re.findall(r'\{(\d+)\}', self.url)))
        except ValueError:
            self.parts = 0

    def __repr__(self):
        return '<ShortRepository: %s>' % self.scheme

    def instance(self, ui, url, create):
        # Should this use the util.url class, or is manual parsing better?
        try:
            url = url.split('://', 1)[1]
        except IndexError:
            raise util.Abort(_("no '://' in scheme url '%s'") % url)
        parts = url.split('/', self.parts)
        if len(parts) > self.parts:
            tail = parts[-1]
            parts = parts[:-1]
        else:
            tail = ''
        context = dict((str(i + 1), v) for i, v in enumerate(parts))
        url = ''.join(self.templater.process(self.url, context)) + tail
        return hg._peerlookup(url).instance(ui, url, create)

def hasdriveletter(orig, path):
    if path:
        for scheme in schemes:
            if path.startswith(scheme + ':'):
                return False
    return orig(path)

schemes = {
    'py': 'http://hg.python.org/',
    'bb': 'https://bitbucket.org/',
    'bb+ssh': 'ssh://[e-mail]/',
    'gcode': 'https://{1}.googlecode.com/hg/',
    'kiln': 'https://{1}.kilnhg.com/Repo/'
    }

def extsetup(ui):
    schemes.update(dict(ui.configitems('schemes')))
    t = templater.engine(lambda x: x)
    for scheme, url in schemes.items():
        if (os.name == 'nt' and len(scheme) == 1 and scheme.isalpha()
            and os.path.exists('%s:\\' % scheme)):
            raise util.Abort(_('custom scheme %s:// conflicts with drive '
                               'letter %s:\\\n') % (scheme, scheme.upper()))
        hg.schemes[scheme] = ShortRepository(url, scheme, t)

    extensions.wrapfunction(util, 'hasdriveletter', hasdriveletter)