server: externalize and streamline mixin setup

mercurial/hgweb/server.py

@@ -1,297 +1,291
 # hgweb/server.py - The standalone hg web server.
 #
 # Copyright 21 May 2005 - (c) 2005 Jake Edge <[e-mail]>
 # Copyright 2005-2007 Matt Mackall <[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.
 
 import os, sys, errno, urllib, BaseHTTPServer, socket, SocketServer, traceback
 from mercurial import hg, util, error
 from hgweb_mod import hgweb
 from hgwebdir_mod import hgwebdir
 from mercurial.i18n import _
 
 def _splitURI(uri):
     """ Return path and query splited from uri
 
     Just like CGI environment, the path is unquoted, the query is
     not.
     """
     if '?' in uri:
         path, query = uri.split('?', 1)
     else:
         path, query = uri, ''
     return urllib.unquote(path), query
 
 class _error_logger(object):
     def __init__(self, handler):
         self.handler = handler
     def flush(self):
         pass
     def write(self, str):
         self.writelines(str.split('\n'))
     def writelines(self, seq):
         for msg in seq:
             self.handler.log_error("HG error:  %s", msg)
 
 class _hgwebhandler(BaseHTTPServer.BaseHTTPRequestHandler):
 
     url_scheme = 'http'
 
     def __init__(self, *args, **kargs):
         self.protocol_version = 'HTTP/1.1'
         BaseHTTPServer.BaseHTTPRequestHandler.__init__(self, *args, **kargs)
 
     def _log_any(self, fp, format, *args):
         fp.write("%s - - [%s] %s\n" % (self.client_address[0],
                                        self.log_date_time_string(),
                                        format % args))
         fp.flush()
 
     def log_error(self, format, *args):
         self._log_any(self.server.errorlog, format, *args)
 
     def log_message(self, format, *args):
         self._log_any(self.server.accesslog, format, *args)
 
     def do_write(self):
         try:
             self.do_hgweb()
         except socket.error, inst:
             if inst[0] != errno.EPIPE:
                 raise
 
     def do_POST(self):
         try:
             self.do_write()
         except StandardError:
             self._start_response("500 Internal Server Error", [])
             self._write("Internal Server Error")
             tb = "".join(traceback.format_exception(*sys.exc_info()))
             self.log_error("Exception happened during processing "
                            "request '%s':\n%s", self.path, tb)
 
     def do_GET(self):
         self.do_POST()
 
     def do_hgweb(self):
         path, query = _splitURI(self.path)
 
         env = {}
         env['GATEWAY_INTERFACE'] = 'CGI/1.1'
         env['REQUEST_METHOD'] = self.command
         env['SERVER_NAME'] = self.server.server_name
         env['SERVER_PORT'] = str(self.server.server_port)
         env['REQUEST_URI'] = self.path
         env['SCRIPT_NAME'] = self.server.prefix
         env['PATH_INFO'] = path[len(self.server.prefix):]
         env['REMOTE_HOST'] = self.client_address[0]
         env['REMOTE_ADDR'] = self.client_address[0]
         if query:
             env['QUERY_STRING'] = query
 
         if self.headers.typeheader is None:
             env['CONTENT_TYPE'] = self.headers.type
         else:
             env['CONTENT_TYPE'] = self.headers.typeheader
         length = self.headers.getheader('content-length')
         if length:
             env['CONTENT_LENGTH'] = length
         for header in [h for h in self.headers.keys()
                        if h not in ('content-type', 'content-length')]:
             hkey = 'HTTP_' + header.replace('-', '_').upper()
             hval = self.headers.getheader(header)
             hval = hval.replace('\n', '').strip()
             if hval:
                 env[hkey] = hval
         env['SERVER_PROTOCOL'] = self.request_version
         env['wsgi.version'] = (1, 0)
         env['wsgi.url_scheme'] = self.url_scheme
         env['wsgi.input'] = self.rfile
         env['wsgi.errors'] = _error_logger(self)
         env['wsgi.multithread'] = isinstance(self.server,
                                              SocketServer.ThreadingMixIn)
         env['wsgi.multiprocess'] = isinstance(self.server,
                                               SocketServer.ForkingMixIn)
         env['wsgi.run_once'] = 0
 
         self.close_connection = True
         self.saved_status = None
         self.saved_headers = []
         self.sent_headers = False
         self.length = None
         for chunk in self.server.application(env, self._start_response):
             self._write(chunk)
 
     def send_headers(self):
         if not self.saved_status:
             raise AssertionError("Sending headers before "
                                  "start_response() called")
         saved_status = self.saved_status.split(None, 1)
         saved_status[0] = int(saved_status[0])
         self.send_response(*saved_status)
         should_close = True
         for h in self.saved_headers:
             self.send_header(*h)
             if h[0].lower() == 'content-length':
                 should_close = False
                 self.length = int(h[1])
         # The value of the Connection header is a list of case-insensitive
         # tokens separated by commas and optional whitespace.
         if 'close' in [token.strip().lower() for token in
                        self.headers.get('connection', '').split(',')]:
             should_close = True
         if should_close:
             self.send_header('Connection', 'close')
         self.close_connection = should_close
         self.end_headers()
         self.sent_headers = True
 
     def _start_response(self, http_status, headers, exc_info=None):
         code, msg = http_status.split(None, 1)
         code = int(code)
         self.saved_status = http_status
         bad_headers = ('connection', 'transfer-encoding')
         self.saved_headers = [h for h in headers
                               if h[0].lower() not in bad_headers]
         return self._write
 
     def _write(self, data):
         if not self.saved_status:
             raise AssertionError("data written before start_response() called")
         elif not self.sent_headers:
             self.send_headers()
         if self.length is not None:
             if len(data) > self.length:
                 raise AssertionError("Content-length header sent, but more "
                                      "bytes than specified are being written.")
             self.length = self.length - len(data)
         self.wfile.write(data)
         self.wfile.flush()
 
 class _shgwebhandler(_hgwebhandler):
 
     url_scheme = 'https'
 
     def setup(self):
         self.connection = self.request
         self.rfile = socket._fileobject(self.request, "rb", self.rbufsize)
         self.wfile = socket._fileobject(self.request, "wb", self.wbufsize)
 
     def do_write(self):
         from OpenSSL.SSL import SysCallError
         try:
             super(_shgwebhandler, self).do_write()
         except SysCallError, inst:
             if inst.args[0] != errno.EPIPE:
                 raise
 
     def handle_one_request(self):
         from OpenSSL.SSL import SysCallError, ZeroReturnError
         try:
             super(_shgwebhandler, self).handle_one_request()
         except (SysCallError, ZeroReturnError):
             self.close_connection = True
             pass
 
+try:
+    from threading import activeCount
+    _mixin = SocketServer.ThreadingMixIn
+except ImportError:
+    if hasattr(os, "fork"):
+        _mixin = SocketServer.ForkingMixIn
+    else:
+        class _mixin:
+            pass
+
 def create_server(ui, repo):
-    use_threads = True
 
     def openlog(opt, default):
         if opt and opt != '-':
             return open(opt, 'a')
         return default
 
     if repo is None:
         myui = ui
     else:
         myui = repo.ui
     address = myui.config("web", "address", "")
     port = int(myui.config("web", "port", 8000))
     prefix = myui.config("web", "prefix", "")
     if prefix:
         prefix = "/" + prefix.strip("/")
     use_ipv6 = myui.configbool("web", "ipv6")
     webdir_conf = myui.config("web", "webdir_conf")
     ssl_cert = myui.config("web", "certificate")
     accesslog = openlog(myui.config("web", "accesslog", "-"), sys.stdout)
     errorlog = openlog(myui.config("web", "errorlog", "-"), sys.stderr)
 
-    if use_threads:
-        try:
-            from threading import activeCount
-        except ImportError:
-            use_threads = False
-
-    if use_threads:
-        _mixin = SocketServer.ThreadingMixIn
-    else:
-        if hasattr(os, "fork"):
-            _mixin = SocketServer.ForkingMixIn
-        else:
-            class _mixin:
-                pass
-
     if webdir_conf:
         hgwebobj = hgwebdir(webdir_conf, ui)
     elif repo is not None:
         hgwebobj = hgweb(hg.repository(repo.ui, repo.root))
     else:
         raise error.RepoError(_("There is no Mercurial repository"
                                 " here (.hg not found)"))
 
     class MercurialHTTPServer(object, _mixin, BaseHTTPServer.HTTPServer):
 
         # SO_REUSEADDR has broken semantics on windows
         if os.name == 'nt':
             allow_reuse_address = 0
 
         def __init__(self, *args, **kargs):
             BaseHTTPServer.HTTPServer.__init__(self, *args, **kargs)
             self.accesslog = accesslog
             self.errorlog = errorlog
             self.daemon_threads = True
             self.application = hgwebobj
 
             if ssl_cert:
                 try:
                     from OpenSSL import SSL
                     ctx = SSL.Context(SSL.SSLv23_METHOD)
                 except ImportError:
                     raise util.Abort(_("SSL support is unavailable"))
                 ctx.use_privatekey_file(ssl_cert)
                 ctx.use_certificate_file(ssl_cert)
                 sock = socket.socket(self.address_family, self.socket_type)
                 self.socket = SSL.Connection(ctx, sock)
                 self.server_bind()
                 self.server_activate()
 
             self.addr, self.port = self.socket.getsockname()[0:2]
             self.prefix = prefix
             self.fqaddr = socket.getfqdn(address)
 
     class IPv6HTTPServer(MercurialHTTPServer):
         address_family = getattr(socket, 'AF_INET6', None)
 
         def __init__(self, *args, **kwargs):
             if self.address_family is None:
                 raise error.RepoError(_('IPv6 is not available on this system'))
             super(IPv6HTTPServer, self).__init__(*args, **kwargs)
 
     if ssl_cert:
         handler = _shgwebhandler
     else:
         handler = _hgwebhandler
 
     # ugly hack due to python issue5853 (for threaded use)
     import mimetypes; mimetypes.init()
 
     try:
         if use_ipv6:
             return IPv6HTTPServer((address, port), handler)
         else:
             return MercurialHTTPServer((address, port), handler)
     except socket.error, inst:
         raise util.Abort(_("cannot start server at '%s:%d': %s")
                          % (address, port, inst.args[1]))