annotate mercurial/url.py @ 26755:bb0b955d050d

streamclone: support for producing and consuming stream clone bundles

Up to this point, stream clones only existed as a dynamically generated
data format produced and consumed during streaming clones. In order to
support this efficient cloning format with the clone bundles feature, we
need a more formal, on disk representation of the streaming clone data.

This patch introduces a new "bundle" type for streaming clones. Unlike
existing bundles, it does not contain changegroup data. It does,
however, share the same concepts like the 4 byte header which identifies
the type of data that follows and the 2 byte abbreviation for
compression types (of which only "UN" is currently supported).

The new bundle format is essentially the existing stream clone version 1
data format with some headers at the beginning.

Content negotiation at stream clone request time checked for repository
format/requirements compatibility before initiating a stream clone. We
can't do active content negotiation when using clone bundles. So, we put
this set of requirements inside the payload so consumers have a built-in
mechanism for checking compatibility before reading and applying lots of
data. Of course, we will also advertise this requirements set in clone
bundles. But that's for another patch.

We currently don't have a mechanism to produce and consume this new
bundle format. This will be implemented in upcoming patches.

It's worth noting that if a legacy client attempts to `hg unbundle` a
stream clone bundle (with the "HGS1" header), it will abort with:
"unknown bundle version S1," which seems appropriate.

# url.py - HTTP handling for mercurial
#
# Copyright 2005, 2006, 2007, 2008 Matt Mackall <[e-mail]>
# Copyright 2006, 2007 Alexis S. L. Carvalho <[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 __future__ import absolute_import

import base64
import cStringIO
import httplib
import os
import socket
import urllib
import urllib2

from .i18n import _
from . import (
    error,
    httpconnection as httpconnectionmod,
    keepalive,
    sslutil,
    util,
)

class passwordmgr(urllib2.HTTPPasswordMgrWithDefaultRealm):
    def __init__(self, ui):
        urllib2.HTTPPasswordMgrWithDefaultRealm.__init__(self)
        self.ui = ui

    def find_user_password(self, realm, authuri):
        authinfo = urllib2.HTTPPasswordMgrWithDefaultRealm.find_user_password(
            self, realm, authuri)
        user, passwd = authinfo
        if user and passwd:
            self._writedebug(user, passwd)
            return (user, passwd)

        if not user or not passwd:
            res = httpconnectionmod.readauthforuri(self.ui, authuri, user)
            if res:
                group, auth = res
                user, passwd = auth.get('username'), auth.get('password')
                self.ui.debug("using auth.%s.* for authentication\n" % group)
        if not user or not passwd:
            u = util.url(authuri)
            u.query = None
            if not self.ui.interactive():
                raise error.Abort(_('http authorization required for %s') %
                                 util.hidepassword(str(u)))

            self.ui.write(_("http authorization required for %s\n") %
                          util.hidepassword(str(u)))
            self.ui.write(_("realm: %s\n") % realm)
            if user:
                self.ui.write(_("user: %s\n") % user)
            else:
                user = self.ui.prompt(_("user:"), default=None)

            if not passwd:
                passwd = self.ui.getpass()

        self.add_password(realm, authuri, user, passwd)
        self._writedebug(user, passwd)
        return (user, passwd)

    def _writedebug(self, user, passwd):
        msg = _('http auth: user %s, password %s\n')
        self.ui.debug(msg % (user, passwd and '*' * len(passwd) or 'not set'))

    def find_stored_password(self, authuri):
        return urllib2.HTTPPasswordMgrWithDefaultRealm.find_user_password(
            self, None, authuri)

class proxyhandler(urllib2.ProxyHandler):
    def __init__(self, ui):
        proxyurl = ui.config("http_proxy", "host") or os.getenv('http_proxy')
        # XXX proxyauthinfo = None

        if proxyurl:
            # proxy can be proper url or host[:port]
            if not (proxyurl.startswith('http:') or
                    proxyurl.startswith('https:')):
                proxyurl = 'http://' + proxyurl + '/'
            proxy = util.url(proxyurl)
            if not proxy.user:
                proxy.user = ui.config("http_proxy", "user")
                proxy.passwd = ui.config("http_proxy", "passwd")

            # see if we should use a proxy for this url
            no_list = ["localhost", "127.0.0.1"]
            no_list.extend([p.lower() for
                            p in ui.configlist("http_proxy", "no")])
            no_list.extend([p.strip().lower() for
                            p in os.getenv("no_proxy", '').split(',')
                            if p.strip()])
            # "http_proxy.always" config is for running tests on localhost
            if ui.configbool("http_proxy", "always"):
                self.no_list = []
            else:
                self.no_list = no_list

            proxyurl = str(proxy)
            proxies = {'http': proxyurl, 'https': proxyurl}
            ui.debug('proxying through http://%s:%s\n' %
                      (proxy.host, proxy.port))
        else:
            proxies = {}

        # urllib2 takes proxy values from the environment and those
        # will take precedence if found. So, if there's a config entry
        # defining a proxy, drop the environment ones
        if ui.config("http_proxy", "host"):
            for env in ["HTTP_PROXY", "http_proxy", "no_proxy"]:
                try:
                    if env in os.environ:
                        del os.environ[env]
                except OSError:
                    pass

        urllib2.ProxyHandler.__init__(self, proxies)
        self.ui = ui

    def proxy_open(self, req, proxy, type_):
        host = req.get_host().split(':')[0]
        for e in self.no_list:
            if host == e:
                return None
            if e.startswith('*.') and host.endswith(e[2:]):
                return None
            if e.startswith('.') and host.endswith(e[1:]):
                return None

        return urllib2.ProxyHandler.proxy_open(self, req, proxy, type_)

def _gen_sendfile(orgsend):
    def _sendfile(self, data):
        # send a file
        if isinstance(data, httpconnectionmod.httpsendfile):
            # if auth required, some data sent twice, so rewind here
            data.seek(0)
            for chunk in util.filechunkiter(data):
                orgsend(self, chunk)
        else:
            orgsend(self, data)
    return _sendfile

has_https = util.safehasattr(urllib2, 'HTTPSHandler')
if has_https:
    try:
        _create_connection = socket.create_connection
    except AttributeError:
        _GLOBAL_DEFAULT_TIMEOUT = object()

        def _create_connection(address, timeout=_GLOBAL_DEFAULT_TIMEOUT,
                               source_address=None):
            # lifted from Python 2.6

            msg = "getaddrinfo returns an empty list"
            host, port = address
            for res in socket.getaddrinfo(host, port, 0, socket.SOCK_STREAM):
                af, socktype, proto, canonname, sa = res
                sock = None
                try:
                    sock = socket.socket(af, socktype, proto)
                    if timeout is not _GLOBAL_DEFAULT_TIMEOUT:
                        sock.settimeout(timeout)
                    if source_address:
                        sock.bind(source_address)
                    sock.connect(sa)
                    return sock

                except socket.error as msg:
                    if sock is not None:
                        sock.close()

            raise socket.error(msg)

class httpconnection(keepalive.HTTPConnection):
    # must be able to send big bundle as stream.
    send = _gen_sendfile(keepalive.HTTPConnection.send)

    def connect(self):
        if has_https and self.realhostport: # use CONNECT proxy
            self.sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
            self.sock.connect((self.host, self.port))
            if _generic_proxytunnel(self):
                # we do not support client X.509 certificates
                self.sock = sslutil.wrapsocket(self.sock, None, None, None,
                                               serverhostname=self.host)
        else:
            keepalive.HTTPConnection.connect(self)

    def getresponse(self):
        proxyres = getattr(self, 'proxyres', None)
        if proxyres:
            if proxyres.will_close:
                self.close()
            self.proxyres = None
            return proxyres
        return keepalive.HTTPConnection.getresponse(self)

# general transaction handler to support different ways to handle
# HTTPS proxying before and after Python 2.6.3.
def _generic_start_transaction(handler, h, req):
    tunnel_host = getattr(req, '_tunnel_host', None)
    if tunnel_host:
        if tunnel_host[:7] not in ['http://', 'https:/']:
            tunnel_host = 'https://' + tunnel_host
        new_tunnel = True
    else:
        tunnel_host = req.get_selector()
        new_tunnel = False

    if new_tunnel or tunnel_host == req.get_full_url(): # has proxy
        u = util.url(tunnel_host)
        if new_tunnel or u.scheme == 'https': # only use CONNECT for HTTPS
            h.realhostport = ':'.join([u.host, (u.port or '443')])
            h.headers = req.headers.copy()
            h.headers.update(handler.parent.addheaders)
            return

    h.realhostport = None
    h.headers = None

def _generic_proxytunnel(self):
    proxyheaders = dict(
            [(x, self.headers[x]) for x in self.headers
             if x.lower().startswith('proxy-')])
    self.send('CONNECT %s HTTP/1.0\r\n' % self.realhostport)
    for header in proxyheaders.iteritems():
        self.send('%s: %s\r\n' % header)
    self.send('\r\n')

    # majority of the following code is duplicated from
    # httplib.HTTPConnection as there are no adequate places to
    # override functions to provide the needed functionality
    res = self.response_class(self.sock,
                              strict=self.strict,
                              method=self._method)

    while True:
        version, status, reason = res._read_status()
        if status != httplib.CONTINUE:
            break
        while True:
            skip = res.fp.readline().strip()
            if not skip:
                break
    res.status = status
    res.reason = reason.strip()

    if res.status == 200:
        while True:
            line = res.fp.readline()
            if line == '\r\n':
                break
        return True

    if version == 'HTTP/1.0':
        res.version = 10
    elif version.startswith('HTTP/1.'):
        res.version = 11
    elif version == 'HTTP/0.9':
        res.version = 9
    else:
        raise httplib.UnknownProtocol(version)

    if res.version == 9:
        res.length = None
        res.chunked = 0
        res.will_close = 1
        res.msg = httplib.HTTPMessage(cStringIO.StringIO())
        return False

    res.msg = httplib.HTTPMessage(res.fp)
    res.msg.fp = None

    # are we using the chunked-style of transfer encoding?
    trenc = res.msg.getheader('transfer-encoding')
    if trenc and trenc.lower() == "chunked":
        res.chunked = 1
        res.chunk_left = None
    else:
        res.chunked = 0

    # will the connection close at the end of the response?
    res.will_close = res._check_close()

    # do we have a Content-Length?
    # NOTE: RFC 2616, section 4.4, #3 says we ignore this if
    # transfer-encoding is "chunked"
    length = res.msg.getheader('content-length')
    if length and not res.chunked:
        try:
            res.length = int(length)
        except ValueError:
            res.length = None
        else:
            if res.length < 0:  # ignore nonsensical negative lengths
                res.length = None
    else:
        res.length = None

    # does the body have a fixed length? (of zero)
    if (status == httplib.NO_CONTENT or status == httplib.NOT_MODIFIED or
        100 <= status < 200 or # 1xx codes
        res._method == 'HEAD'):
        res.length = 0

    # if the connection remains open, and we aren't using chunked, and
    # a content-length was not provided, then assume that the connection
    # WILL close.
    if (not res.will_close and
       not res.chunked and
       res.length is None):
        res.will_close = 1

    self.proxyres = res

    return False

class httphandler(keepalive.HTTPHandler):
    def http_open(self, req):
        return self.do_open(httpconnection, req)

    def _start_transaction(self, h, req):
        _generic_start_transaction(self, h, req)
        return keepalive.HTTPHandler._start_transaction(self, h, req)

if has_https:
    class httpsconnection(httplib.HTTPConnection):
        response_class = keepalive.HTTPResponse
        default_port = httplib.HTTPS_PORT
        # must be able to send big bundle as stream.
        send = _gen_sendfile(keepalive.safesend)
        getresponse = keepalive.wrapgetresponse(httplib.HTTPConnection)

        def __init__(self, host, port=None, key_file=None, cert_file=None,
                     *args, **kwargs):
            httplib.HTTPConnection.__init__(self, host, port, *args, **kwargs)
            self.key_file = key_file
            self.cert_file = cert_file

        def connect(self):
            self.sock = _create_connection((self.host, self.port))

            host = self.host
            if self.realhostport: # use CONNECT proxy
                _generic_proxytunnel(self)
                host = self.realhostport.rsplit(':', 1)[0]
            self.sock = sslutil.wrapsocket(
                self.sock, self.key_file, self.cert_file, serverhostname=host,
                **sslutil.sslkwargs(self.ui, host))
            sslutil.validator(self.ui, host)(self.sock)

    class httpshandler(keepalive.KeepAliveHandler, urllib2.HTTPSHandler):
        def __init__(self, ui):
            keepalive.KeepAliveHandler.__init__(self)
            urllib2.HTTPSHandler.__init__(self)
            self.ui = ui
            self.pwmgr = passwordmgr(self.ui)

        def _start_transaction(self, h, req):
            _generic_start_transaction(self, h, req)
            return keepalive.KeepAliveHandler._start_transaction(self, h, req)

        def https_open(self, req):
            # req.get_full_url() does not contain credentials and we may
            # need them to match the certificates.
            url = req.get_full_url()
            user, password = self.pwmgr.find_stored_password(url)
            res = httpconnectionmod.readauthforuri(self.ui, url, user)
            if res:
                group, auth = res
                self.auth = auth
                self.ui.debug("using auth.%s.* for authentication\n" % group)
            else:
                self.auth = None
            return self.do_open(self._makeconnection, req)

        def _makeconnection(self, host, port=None, *args, **kwargs):
            keyfile = None
            certfile = None

            if len(args) >= 1: # key_file
                keyfile = args[0]
            if len(args) >= 2: # cert_file
                certfile = args[1]
            args = args[2:]

            # if the user has specified different key/cert files in
            # hgrc, we prefer these
            if self.auth and 'key' in self.auth and 'cert' in self.auth:
                keyfile = self.auth['key']
                certfile = self.auth['cert']

            conn = httpsconnection(host, port, keyfile, certfile, *args,
                                   **kwargs)
            conn.ui = self.ui
            return conn

class httpdigestauthhandler(urllib2.HTTPDigestAuthHandler):
    def __init__(self, *args, **kwargs):
        urllib2.HTTPDigestAuthHandler.__init__(self, *args, **kwargs)
        self.retried_req = None

    def reset_retry_count(self):
        # Python 2.6.5 will call this on 401 or 407 errors and thus loop
        # forever. We disable reset_retry_count completely and reset in
        # http_error_auth_reqed instead.
        pass

    def http_error_auth_reqed(self, auth_header, host, req, headers):
        # Reset the retry counter once for each request.
        if req is not self.retried_req:
            self.retried_req = req
            self.retried = 0
        # In python < 2.5 AbstractDigestAuthHandler raises a ValueError if
        # it doesn't know about the auth type requested. This can happen if
        # somebody is using BasicAuth and types a bad password.
        try:
            return urllib2.HTTPDigestAuthHandler.http_error_auth_reqed(
                        self, auth_header, host, req, headers)
        except ValueError as inst:
            arg = inst.args[0]
            if arg.startswith("AbstractDigestAuthHandler doesn't know "):
                return
            raise

class httpbasicauthhandler(urllib2.HTTPBasicAuthHandler):
    def __init__(self, *args, **kwargs):
        self.auth = None
        urllib2.HTTPBasicAuthHandler.__init__(self, *args, **kwargs)
        self.retried_req = None

    def http_request(self, request):
        if self.auth:
            request.add_unredirected_header(self.auth_header, self.auth)

        return request

    def https_request(self, request):
        if self.auth:
            request.add_unredirected_header(self.auth_header, self.auth)

        return request

    def reset_retry_count(self):
        # Python 2.6.5 will call this on 401 or 407 errors and thus loop
        # forever. We disable reset_retry_count completely and reset in
        # http_error_auth_reqed instead.
        pass

    def http_error_auth_reqed(self, auth_header, host, req, headers):
        # Reset the retry counter once for each request.
        if req is not self.retried_req:
            self.retried_req = req
            self.retried = 0
        return urllib2.HTTPBasicAuthHandler.http_error_auth_reqed(
                        self, auth_header, host, req, headers)

    def retry_http_basic_auth(self, host, req, realm):
        user, pw = self.passwd.find_user_password(realm, req.get_full_url())
        if pw is not None:
            raw = "%s:%s" % (user, pw)
            auth = 'Basic %s' % base64.b64encode(raw).strip()
            if req.headers.get(self.auth_header, None) == auth:
                return None
            self.auth = auth
            req.add_unredirected_header(self.auth_header, auth)
            return self.parent.open(req)
        else:
            return None

handlerfuncs = []

def opener(ui, authinfo=None):
    '''
    construct an opener suitable for urllib2
    authinfo will be added to the password manager
    '''
    # experimental config: ui.usehttp2
    if ui.configbool('ui', 'usehttp2', False):
        handlers = [httpconnectionmod.http2handler(ui, passwordmgr(ui))]
    else:
        handlers = [httphandler()]
        if has_https:
            handlers.append(httpshandler(ui))

    handlers.append(proxyhandler(ui))

    passmgr = passwordmgr(ui)
    if authinfo is not None:
        passmgr.add_password(*authinfo)
        user, passwd = authinfo[2:4]
        ui.debug('http auth: user %s, password %s\n' %
                 (user, passwd and '*' * len(passwd) or 'not set'))

    handlers.extend((httpbasicauthhandler(passmgr),
                     httpdigestauthhandler(passmgr)))
    handlers.extend([h(ui, passmgr) for h in handlerfuncs])
    opener = urllib2.build_opener(*handlers)

    # 1.0 here is the _protocol_ version
    opener.addheaders = [('User-agent', 'mercurial/proto-1.0')]
    opener.addheaders.append(('Accept', 'application/mercurial-0.1'))
    return opener

def open(ui, url_, data=None):
    u = util.url(url_)
    if u.scheme:
        u.scheme = u.scheme.lower()
        url_, authinfo = u.authinfo()
    else:
        path = util.normpath(os.path.abspath(url_))
        url_ = 'file://' + urllib.pathname2url(path)
        authinfo = None
    return opener(ui, authinfo).open(url_, data)