HTTPS: fix python2.3, persistent connections, don't explode if SSL is not available

The urllib2 differences between python 2.3 and 2.4 are hidden by
using keepalive.py, which also gives us support for persistent
connections.

Support for HTTPS is enabled only if there's a HTTPSHandler class in
urllib2.

It's not possible to have separate classes as handlers for HTTP and
HTTPS:  to support persistent HTTPS connections, we need a class that
inherits from both keepalive.HTTPHandler and urllib2.HTTPSHandler.  If
we try to pass (an instance of) this class and (an instance of) the
httphandler class to urllib2.build_opener, this function ends up getting
confused, since both classes are subclasses of the HTTPHandler default
handler, and raises an exception.

mercurial/httprepo.py

@@ -1,325 +1,334 b''
 # httprepo.py - HTTP repository proxy classes for mercurial
 #
 # Copyright 2005 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 node import *
 from remoterepo import *
 from i18n import gettext as _
 from demandload import *
 demandload(globals(), "hg os urllib urllib2 urlparse zlib util httplib")
 demandload(globals(), "errno keepalive tempfile socket")
 
 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:
             return (user, passwd)
 
         if not self.ui.interactive:
             raise util.Abort(_('http authorization required'))
 
         self.ui.write(_("http authorization required\n"))
         self.ui.status(_("realm: %s\n") % realm)
         if user:
             self.ui.status(_("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)
         return (user, passwd)
 
 def netlocsplit(netloc):
     '''split [user[:passwd]@]host[:port] into 4-tuple.'''
 
     a = netloc.find('@')
     if a == -1:
         user, passwd = None, None
     else:
         userpass, netloc = netloc[:a], netloc[a+1:]
         c = userpass.find(':')
         if c == -1:
             user, passwd = urllib.unquote(userpass), None
         else:
             user = urllib.unquote(userpass[:c])
             passwd = urllib.unquote(userpass[c+1:])
     c = netloc.find(':')
     if c == -1:
         host, port = netloc, None
     else:
         host, port = netloc[:c], netloc[c+1:]
     return host, port, user, passwd
 
 def netlocunsplit(host, port, user=None, passwd=None):
     '''turn host, port, user, passwd into [user[:passwd]@]host[:port].'''
     if port:
         hostport = host + ':' + port
     else:
         hostport = host
     if user:
         if passwd:
             userpass = urllib.quote(user) + ':' + urllib.quote(passwd)
         else:
             userpass = urllib.quote(user)
         return userpass + '@' + hostport
     return hostport
 
 class httpconnection(keepalive.HTTPConnection):
     # must be able to send big bundle as stream.
 
     def send(self, data):
         if isinstance(data, str):
             keepalive.HTTPConnection.send(self, data)
         else:
             # if auth required, some data sent twice, so rewind here
             data.seek(0)
             for chunk in util.filechunkiter(data):
                 keepalive.HTTPConnection.send(self, chunk)
 
-class httphandler(keepalive.HTTPHandler):
+class basehttphandler(keepalive.HTTPHandler):
     def http_open(self, req):
         return self.do_open(httpconnection, req)
 
+has_https = hasattr(urllib2, 'HTTPSHandler')
+if has_https:
 class httpsconnection(httplib.HTTPSConnection):
+        response_class = keepalive.HTTPResponse
     # must be able to send big bundle as stream.
 
     def send(self, data):
         if isinstance(data, str):
             httplib.HTTPSConnection.send(self, data)
         else:
             # if auth required, some data sent twice, so rewind here
             data.seek(0)
             for chunk in util.filechunkiter(data):
                 httplib.HTTPSConnection.send(self, chunk)
 
-class httpshandler(urllib2.HTTPSHandler):
+    class httphandler(basehttphandler, urllib2.HTTPSHandler):
     def https_open(self, req):
         return self.do_open(httpsconnection, req)
+else:
+    class httphandler(basehttphandler):
+        pass
 
 class httprepository(remoterepository):
     def __init__(self, ui, path):
         self.caps = None
         scheme, netloc, urlpath, query, frag = urlparse.urlsplit(path)
         if query or frag:
             raise util.Abort(_('unsupported URL component: "%s"') %
                              (query or frag))
         if not urlpath: urlpath = '/'
         host, port, user, passwd = netlocsplit(netloc)
 
         # urllib cannot handle URLs with embedded user or passwd
         self.url = urlparse.urlunsplit((scheme, netlocunsplit(host, port),
                                         urlpath, '', ''))
         self.ui = ui
 
         proxyurl = ui.config("http_proxy", "host") or os.getenv('http_proxy')
         proxyauthinfo = None
         handler = httphandler()
 
         if proxyurl:
             # proxy can be proper url or host[:port]
             if not (proxyurl.startswith('http:') or
                     proxyurl.startswith('https:')):
                 proxyurl = 'http://' + proxyurl + '/'
             snpqf = urlparse.urlsplit(proxyurl)
             proxyscheme, proxynetloc, proxypath, proxyquery, proxyfrag = snpqf
             hpup = netlocsplit(proxynetloc)
 
             proxyhost, proxyport, proxyuser, proxypasswd = hpup
             if not proxyuser:
                 proxyuser = ui.config("http_proxy", "user")
                 proxypasswd = 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 (not ui.configbool("http_proxy", "always") and
                 host.lower() in no_list):
                 ui.debug(_('disabling proxy for %s\n') % host)
             else:
                 proxyurl = urlparse.urlunsplit((
                     proxyscheme, netlocunsplit(proxyhost, proxyport,
                                                proxyuser, proxypasswd or ''),
                     proxypath, proxyquery, proxyfrag))
                 handler = urllib2.ProxyHandler({scheme: proxyurl})
                 ui.debug(_('proxying through %s\n') % proxyurl)
 
         # urllib2 takes proxy values from the environment and those
         # will take precedence if found, so drop them
         for env in ["HTTP_PROXY", "http_proxy", "no_proxy"]:
             try:
                 if os.environ.has_key(env):
                     del os.environ[env]
             except OSError:
                 pass
 
         passmgr = passwordmgr(ui)
         if user:
             ui.debug(_('http auth: user %s, password %s\n') %
                      (user, passwd and '*' * len(passwd) or 'not set'))
             passmgr.add_password(None, host, user, passwd or '')
 
         opener = urllib2.build_opener(
             handler,
-            httpshandler(),
             urllib2.HTTPBasicAuthHandler(passmgr),
             urllib2.HTTPDigestAuthHandler(passmgr))
 
         # 1.0 here is the _protocol_ version
         opener.addheaders = [('User-agent', 'mercurial/proto-1.0')]
         urllib2.install_opener(opener)
 
     # look up capabilities only when needed
 
     def get_caps(self):
         if self.caps is None:
             try:
                 self.caps = self.do_read('capabilities').split()
             except hg.RepoError:
                 self.caps = ()
             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 = urllib.urlencode(q)
         cu = "%s?%s" % (self.url, qs)
         try:
             resp = urllib2.urlopen(urllib2.Request(cu, data, headers))
         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.print_exc()
             raise IOError(None, inst)
         try:
             proto = resp.getheader('content-type')
         except AttributeError:
             proto = resp.headers['content-type']
 
         # accept old "text/plain" and "application/hg-changegroup" for now
         if not proto.startswith('application/mercurial') and \
                not proto.startswith('text/plain') and \
                not proto.startswith('application/hg-changegroup'):
             raise hg.RepoError(_("'%s' does not appear to be an hg repository") %
                                self.url)
 
         if proto.startswith('application/mercurial'):
             version = proto[22:]
             if float(version) > 0.1:
                 raise hg.RepoError(_("'%s' uses newer protocol %s") %
                                    (self.url, 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 heads(self):
         d = self.do_read("heads")
         try:
             return map(bin, d[:-1].split(" "))
         except:
             self.ui.warn(_("unexpected response:\n") + d[:400] + "\n...\n")
             raise
 
     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:
             self.ui.warn(_("unexpected response:\n") + d[:400] + "\n...\n")
             raise
 
     def between(self, pairs):
         n = "\n".join(["-".join(map(hex, p)) for p in pairs])
         d = self.do_read("between", pairs=n)
         try:
             p = [ l and map(bin, l.split(" ")) or [] for l in d.splitlines() ]
             return p
         except:
             self.ui.warn(_("unexpected response:\n") + d[:400] + "\n...\n")
             raise
 
     def changegroup(self, nodes, kind):
         n = " ".join(map(hex, nodes))
         f = self.do_cmd("changegroup", roots=n)
         bytes = 0
 
         def zgenerator(f):
             zd = zlib.decompressobj()
             try:
                 for chnk in f:
                     yield zd.decompress(chnk)
             except httplib.HTTPException, inst:
                 raise IOError(None, _('connection ended unexpectedly'))
             yield zd.flush()
 
         return util.chunkbuffer(zgenerator(util.filechunkiter(f)))
 
     def unbundle(self, cg, heads, source):
         # have to stream bundle to a temp file because we do not have
         # http 1.1 chunked transfer.
 
         fd, tempname = tempfile.mkstemp(prefix='hg-unbundle-')
         fp = os.fdopen(fd, 'wb+')
         try:
             for chunk in util.filechunkiter(cg):
                 fp.write(chunk)
             length = fp.tell()
             try:
                 rfp = self.do_cmd(
                     'unbundle', data=fp,
                     headers={'content-length': length,
                              'content-type': 'application/octet-stream'},
                     heads=' '.join(map(hex, heads)))
                 try:
                     ret = int(rfp.readline())
                     self.ui.write(rfp.read())
                     return ret
                 finally:
                     rfp.close()
             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)
 
 class httpsrepository(httprepository):
-    pass
+    def __init__(self, ui, path):
+        if not has_https:
+            raise util.Abort(_('Python support for SSL and HTTPS '
+                               'is not installed'))
+        httprepository.__init__(self, ui, path)