mercurial/hgweb/server.py

localrepository.status: only acquire wlock if actually needed.

This speeds up the common case of not needing to update the dirstate,
and avoids the need to reload and parse the dirstate "just in case".

# hgweb/server.py - The standalone hg web server.
#
# Copyright 21 May 2005 - (c) 2005 Jake Edge <[e-mail]>
# Copyright 2005, 2006 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.

import os, sys, errno, urllib, BaseHTTPServer, socket, SocketServer, traceback
from mercurial import ui, hg, util, templater
from hgweb_mod import hgweb
from hgwebdir_mod import hgwebdir
from request import wsgiapplication
from mercurial.i18n import gettext as _

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(object, BaseHTTPServer.BaseHTTPRequestHandler):
    def __init__(self, *args, **kargs):
        self.protocol_version = 'HTTP/1.1'
        BaseHTTPServer.BaseHTTPRequestHandler.__init__(self, *args, **kargs)

    def log_error(self, format, *args):
        errorlog = self.server.errorlog
        errorlog.write("%s - - [%s] %s\n" % (self.address_string(),
                                             self.log_date_time_string(),
                                             format % args))

    def log_message(self, format, *args):
        accesslog = self.server.accesslog
        accesslog.write("%s - - [%s] %s\n" % (self.address_string(),
                                              self.log_date_time_string(),
                                              format % args))

    def do_POST(self):
        try:
            try:
                self.do_hgweb()
            except socket.error, inst:
                if inst[0] != errno.EPIPE:
                    raise
        except StandardError, inst:
            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_info, 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['PATH_INFO'] = path_info
        if query:
            env['QUERY_STRING'] = query
        host = self.address_string()
        if host != self.client_address[0]:
            env['REMOTE_HOST'] = host
            env['REMOTE_ADDR'] = self.client_address[0]

        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'] = 'http'
        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
        req = self.server.reqmaker(env, self._start_response)
        for data in req:
            if data:
                self._write(data)

    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()

def create_server(ui, repo):
    use_threads = True

    def openlog(opt, default):
        if opt and opt != '-':
            return open(opt, 'w')
        return default

    address = ui.config("web", "address", "")
    port = int(ui.config("web", "port", 8000))
    use_ipv6 = ui.configbool("web", "ipv6")
    webdir_conf = ui.config("web", "webdir_conf")
    accesslog = openlog(ui.config("web", "accesslog", "-"), sys.stdout)
    errorlog = openlog(ui.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

    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
            def make_handler():
                if webdir_conf:
                    hgwebobj = hgwebdir(webdir_conf, ui)
                elif repo is not None:
                    hgwebobj = hgweb(hg.repository(repo.ui, repo.root))
                else:
                    raise hg.RepoError(_("There is no Mercurial repository here"
                                         " (.hg not found)"))
                return hgwebobj
            self.reqmaker = wsgiapplication(make_handler)

            addr, port = self.socket.getsockname()[:2]
            if addr in ('0.0.0.0', '::'):
                addr = socket.gethostname()
            else:
                try:
                    addr = socket.gethostbyaddr(addr)[0]
                except socket.error:
                    pass
            self.addr, self.port = addr, port

    class IPv6HTTPServer(MercurialHTTPServer):
        address_family = getattr(socket, 'AF_INET6', None)

        def __init__(self, *args, **kwargs):
            if self.address_family is None:
                raise hg.RepoError(_('IPv6 not available on this system'))
            super(IPv6HTTPServer, self).__init__(*args, **kwargs)

    try:
        if use_ipv6:
            return IPv6HTTPServer((address, port), _hgwebhandler)
        else:
            return MercurialHTTPServer((address, port), _hgwebhandler)
    except socket.error, inst:
        raise util.Abort(_('cannot start server: %s') % inst.args[1])