mercurial/httprepo.py

dagparser: parses and formats DAGs as concise text

As discussed during the sprint. See the doc comment and doctests
for specification and examples. This is used in subsequent patches
to export revlog and changelog DAGs, and to generate a repo with
a given changelog DAG.

# httprepo.py - HTTP repository proxy classes for mercurial
#
# Copyright 2005, 2006 Matt Mackall <[e-mail]>
# Copyright 2006 Vadim Gelfer <[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.

from node import bin, hex, nullid
from i18n import _
import repo, changegroup, statichttprepo, error, url, util
import os, urllib, urllib2, urlparse, zlib, httplib
import errno, socket
import encoding

def zgenerator(f):
    zd = zlib.decompressobj()
    try:
        for chunk in util.filechunkiter(f):
            yield zd.decompress(chunk)
    except httplib.HTTPException:
        raise IOError(None, _('connection ended unexpectedly'))
    yield zd.flush()

class httprepository(repo.repository):
    def __init__(self, ui, path):
        self.path = path
        self.caps = None
        self.handler = None
        scheme, netloc, urlpath, query, frag = urlparse.urlsplit(path)
        if query or frag:
            raise util.Abort(_('unsupported URL component: "%s"') %
                             (query or frag))

        # urllib cannot handle URLs with embedded user or passwd
        self._url, authinfo = url.getauthinfo(path)

        self.ui = ui
        self.ui.debug('using %s\n' % self._url)

        self.urlopener = url.opener(ui, authinfo)

    def __del__(self):
        for h in self.urlopener.handlers:
            h.close()
            if hasattr(h, "close_all"):
                h.close_all()

    def url(self):
        return self.path

    # look up capabilities only when needed

    def get_caps(self):
        if self.caps is None:
            try:
                self.caps = set(self.do_read('capabilities').split())
            except error.RepoError:
                self.caps = set()
            self.ui.debug('capabilities: %s\n' %
                          (' '.join(self.caps or ['none'])))
        return self.caps

    capabilities = property(get_caps)

    def lock(self):
        raise util.Abort(_('operation not supported over http'))

    def do_cmd(self, cmd, **args):
        data = args.pop('data', None)
        headers = args.pop('headers', {})
        self.ui.debug("sending %s command\n" % cmd)
        q = {"cmd": cmd}
        q.update(args)
        qs = '?%s' % urllib.urlencode(q)
        cu = "%s%s" % (self._url, qs)
        req = urllib2.Request(cu, data, headers)
        if data is not None:
            # len(data) is broken if data doesn't fit into Py_ssize_t
            # add the header ourself to avoid OverflowError
            size = data.__len__()
            self.ui.debug("sending %s bytes\n" % size)
            req.add_unredirected_header('Content-Length', '%d' % size)
        try:
            resp = self.urlopener.open(req)
        except urllib2.HTTPError, inst:
            if inst.code == 401:
                raise util.Abort(_('authorization failed'))
            raise
        except httplib.HTTPException, inst:
            self.ui.debug('http error while sending %s command\n' % cmd)
            self.ui.traceback()
            raise IOError(None, inst)
        except IndexError:
            # this only happens with Python 2.3, later versions raise URLError
            raise util.Abort(_('http error, possibly caused by proxy setting'))
        # record the url we got redirected to
        resp_url = resp.geturl()
        if resp_url.endswith(qs):
            resp_url = resp_url[:-len(qs)]
        if self._url.rstrip('/') != resp_url.rstrip('/'):
            self.ui.status(_('real URL is %s\n') % resp_url)
        self._url = resp_url
        try:
            proto = resp.getheader('content-type')
        except AttributeError:
            proto = resp.headers['content-type']

        safeurl = url.hidepassword(self._url)
        # accept old "text/plain" and "application/hg-changegroup" for now
        if not (proto.startswith('application/mercurial-') or
                proto.startswith('text/plain') or
                proto.startswith('application/hg-changegroup')):
            self.ui.debug("requested URL: '%s'\n" % url.hidepassword(cu))
            raise error.RepoError(
                _("'%s' does not appear to be an hg repository:\n"
                  "---%%<--- (%s)\n%s\n---%%<---\n")
                % (safeurl, proto, resp.read()))

        if proto.startswith('application/mercurial-'):
            try:
                version = proto.split('-', 1)[1]
                version_info = tuple([int(n) for n in version.split('.')])
            except ValueError:
                raise error.RepoError(_("'%s' sent a broken Content-Type "
                                        "header (%s)") % (safeurl, proto))
            if version_info > (0, 1):
                raise error.RepoError(_("'%s' uses newer protocol %s") %
                                      (safeurl, version))

        return resp

    def do_read(self, cmd, **args):
        fp = self.do_cmd(cmd, **args)
        try:
            return fp.read()
        finally:
            # if using keepalive, allow connection to be reused
            fp.close()

    def lookup(self, key):
        self.requirecap('lookup', _('look up remote revision'))
        d = self.do_cmd("lookup", key = key).read()
        success, data = d[:-1].split(' ', 1)
        if int(success):
            return bin(data)
        raise error.RepoError(data)

    def heads(self):
        d = self.do_read("heads")
        try:
            return map(bin, d[:-1].split(" "))
        except:
            raise error.ResponseError(_("unexpected response:"), d)

    def branchmap(self):
        d = self.do_read("branchmap")
        try:
            branchmap = {}
            for branchpart in d.splitlines():
                branchheads = branchpart.split(' ')
                branchname = urllib.unquote(branchheads[0])
                # Earlier servers (1.3.x) send branch names in (their) local
                # charset. The best we can do is assume it's identical to our
                # own local charset, in case it's not utf-8.
                try:
                    branchname.decode('utf-8')
                except UnicodeDecodeError:
                    branchname = encoding.fromlocal(branchname)
                branchheads = [bin(x) for x in branchheads[1:]]
                branchmap[branchname] = branchheads
            return branchmap
        except:
            raise error.ResponseError(_("unexpected response:"), d)

    def branches(self, nodes):
        n = " ".join(map(hex, nodes))
        d = self.do_read("branches", nodes=n)
        try:
            br = [tuple(map(bin, b.split(" "))) for b in d.splitlines()]
            return br
        except:
            raise error.ResponseError(_("unexpected response:"), d)

    def between(self, pairs):
        batch = 8 # avoid giant requests
        r = []
        for i in xrange(0, len(pairs), batch):
            n = " ".join(["-".join(map(hex, p)) for p in pairs[i:i + batch]])
            d = self.do_read("between", pairs=n)
            try:
                r += [l and map(bin, l.split(" ")) or []
                      for l in d.splitlines()]
            except:
                raise error.ResponseError(_("unexpected response:"), d)
        return r

    def changegroup(self, nodes, kind):
        n = " ".join(map(hex, nodes))
        f = self.do_cmd("changegroup", roots=n)
        return util.chunkbuffer(zgenerator(f))

    def changegroupsubset(self, bases, heads, source):
        self.requirecap('changegroupsubset', _('look up remote changes'))
        baselst = " ".join([hex(n) for n in bases])
        headlst = " ".join([hex(n) for n in heads])
        f = self.do_cmd("changegroupsubset", bases=baselst, heads=headlst)
        return util.chunkbuffer(zgenerator(f))

    def unbundle(self, cg, heads, source):
        '''Send cg (a readable file-like object representing the
        changegroup to push, typically a chunkbuffer object) to the
        remote server as a bundle. Return an integer response code:
        non-zero indicates a successful push (see
        localrepository.addchangegroup()), and zero indicates either
        error or nothing to push.'''
        # have to stream bundle to a temp file because we do not have
        # http 1.1 chunked transfer.

        type = ""
        types = self.capable('unbundle')
        # servers older than d1b16a746db6 will send 'unbundle' as a
        # boolean capability
        try:
            types = types.split(',')
        except AttributeError:
            types = [""]
        if types:
            for x in types:
                if x in changegroup.bundletypes:
                    type = x
                    break

        tempname = changegroup.writebundle(cg, None, type)
        fp = url.httpsendfile(tempname, "rb")
        try:
            try:
                resp = self.do_read(
                     'unbundle', data=fp,
                     headers={'Content-Type': 'application/mercurial-0.1'},
                     heads=' '.join(map(hex, heads)))
                resp_code, output = resp.split('\n', 1)
                try:
                    ret = int(resp_code)
                except ValueError, err:
                    raise error.ResponseError(
                            _('push failed (unexpected response):'), resp)
                for l in output.splitlines(True):
                    self.ui.status(_('remote: '), l)
                return ret
            except socket.error, err:
                if err[0] in (errno.ECONNRESET, errno.EPIPE):
                    raise util.Abort(_('push failed: %s') % err[1])
                raise util.Abort(err[1])
        finally:
            fp.close()
            os.unlink(tempname)

    def stream_out(self):
        return self.do_cmd('stream_out')

class httpsrepository(httprepository):
    def __init__(self, ui, path):
        if not url.has_https:
            raise util.Abort(_('Python support for SSL and HTTPS '
                               'is not installed'))
        httprepository.__init__(self, ui, path)

def instance(ui, path, create):
    if create:
        raise util.Abort(_('cannot create new http repository'))
    try:
        if path.startswith('https:'):
            inst = httpsrepository(ui, path)
        else:
            inst = httprepository(ui, path)
        inst.between([(nullid, nullid)])
        return inst
    except error.RepoError:
        ui.note('(falling back to static-http)\n')
        return statichttprepo.instance(ui, "static-" + path, create)