view mercurial/statichttprepo.py @ 6144:08e0825b8106

revlog.revision: avoid opening the datafile without need.

If there's no inline data, revlog.revision opens the data file every
time it's called.  This is useful if we're going to call chunk many
times, but, if we're going to call it only once, it's better to let
chunk open the file - if we're lucky, all the data we're going to need
is already cached and we won't need to even look at the file.

# statichttprepo.py - simple http repository class for mercurial
#
# This provides read-only repo access to repositories exported via static http
#
# Copyright 2005-2007 Matt Mackall <[e-mail]>
#
# This software may be used and distributed according to the terms
# of the GNU General Public License, incorporated herein by reference.

from i18n import _
import changelog, filelog, httprangereader
import repo, localrepo, manifest, util
import urllib, urllib2, errno

class rangereader(httprangereader.httprangereader):
    def read(self, size=None):
        try:
            return httprangereader.httprangereader.read(self, size)
        except urllib2.HTTPError, inst:
            num = inst.code == 404 and errno.ENOENT or None
            raise IOError(num, inst)
        except urllib2.URLError, inst:
            raise IOError(None, inst.reason[1])

def opener(base):
    """return a function that opens files over http"""
    p = base
    def o(path, mode="r"):
        f = "/".join((p, urllib.quote(path)))
        return rangereader(f)
    return o

class statichttprepository(localrepo.localrepository):
    def __init__(self, ui, path):
        self._url = path
        self.ui = ui

        self.path = path.rstrip('/') + "/.hg"
        self.opener = opener(self.path)

        # find requirements
        try:
            requirements = self.opener("requires").read().splitlines()
        except IOError, inst:
            if inst.errno == errno.ENOENT:
                msg = _("'%s' does not appear to be an hg repository") % path
                raise repo.RepoError(msg)
            else:
                requirements = []

        # check them
        for r in requirements:
            if r not in self.supported:
                raise repo.RepoError(_("requirement '%s' not supported") % r)

        # setup store
        if "store" in requirements:
            self.encodefn = util.encodefilename
            self.decodefn = util.decodefilename
            self.spath = self.path + "/store"
        else:
            self.encodefn = lambda x: x
            self.decodefn = lambda x: x
            self.spath = self.path
        self.sopener = util.encodedopener(opener(self.spath), self.encodefn)

        self.manifest = manifest.manifest(self.sopener)
        self.changelog = changelog.changelog(self.sopener)
        self.tagscache = None
        self.nodetagscache = None
        self.encodepats = None
        self.decodepats = None

    def url(self):
        return 'static-' + self._url

    def dev(self):
        return -1

    def local(self):
        return False

def instance(ui, path, create):
    if create:
        raise util.Abort(_('cannot create new static-http repository'))
    return statichttprepository(ui, path[7:])