etwist/server.py
author Julien Cristau <julien.cristau@logilab.fr>
Thu, 10 Oct 2013 10:02:29 +0200
branchstable
changeset 9306 8ab0e601d418
parent 8930 6a02be304486
child 9030 c1d5e8ca15ea
child 9147 01124cfd4b1f
permissions -rw-r--r--
[web] don't rename resources in gen-static-datadir We should use the result from WebConfiguration.locate_resource to know which file to copy, not what name to copy it to. The destination file should be the name of the resource, as the client will request it. This matters in the case of cubicweb.css which locate_resource might rewrite to cubicweb.old.css. Closes #3206129

# copyright 2003-2012 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
# contact http://www.logilab.fr/ -- mailto:contact@logilab.fr
#
# This file is part of CubicWeb.
#
# CubicWeb is free software: you can redistribute it and/or modify it under the
# terms of the GNU Lesser General Public License as published by the Free
# Software Foundation, either version 2.1 of the License, or (at your option)
# any later version.
#
# CubicWeb is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more
# details.
#
# You should have received a copy of the GNU Lesser General Public License along
# with CubicWeb.  If not, see <http://www.gnu.org/licenses/>.
"""twisted server for CubicWeb web instances"""
__docformat__ = "restructuredtext en"

import sys
import select
import traceback
import threading
from urlparse import urlsplit, urlunsplit
from cgi import FieldStorage, parse_header

from twisted.internet import reactor, task, threads
from twisted.web import http, server
from twisted.web import resource
from twisted.web.server import NOT_DONE_YET


from logilab.mtconverter import xml_escape
from logilab.common.decorators import monkeypatch

from cubicweb import ConfigurationError, CW_EVENT_MANAGER
from cubicweb.utils import json_dumps
from cubicweb.web import DirectResponse
from cubicweb.web.application import CubicWebPublisher
from cubicweb.etwist.request import CubicWebTwistedRequestAdapter
from cubicweb.etwist.http import HTTPResponse

def start_task(interval, func):
    lc = task.LoopingCall(func)
    # wait until interval has expired to actually start the task, else we have
    # to wait all tasks to be finished for the server to be actually started
    lc.start(interval, now=False)

def host_prefixed_baseurl(baseurl, host):
    scheme, netloc, url, query, fragment = urlsplit(baseurl)
    netloc_domain = '.' + '.'.join(netloc.split('.')[-2:])
    if host.endswith(netloc_domain):
        netloc = host
    baseurl = urlunsplit((scheme, netloc, url, query, fragment))
    return baseurl


class CubicWebRootResource(resource.Resource):
    def __init__(self, config, vreg=None):
        resource.Resource.__init__(self)
        self.config = config
        # instantiate publisher here and not in init_publisher to get some
        # checks done before daemonization (eg versions consistency)
        self.appli = CubicWebPublisher(config, vreg=vreg)
        self.base_url = config['base-url']
        self.https_url = config['https-url']
        global MAX_POST_LENGTH
        MAX_POST_LENGTH = config['max-post-length']

    def init_publisher(self):
        config = self.config
        # when we have an in-memory repository, clean unused sessions every XX
        # seconds and properly shutdown the server
        if config['repository-uri'] == 'inmemory://':
            if config.pyro_enabled():
                # if pyro is enabled, we have to register to the pyro name
                # server, create a pyro daemon, and create a task to handle pyro
                # requests
                self.pyro_daemon = self.appli.repo.pyro_register()
                self.pyro_listen_timeout = 0.02
                self.appli.repo.looping_task(1, self.pyro_loop_event)
            if config.mode != 'test':
                reactor.addSystemEventTrigger('before', 'shutdown',
                                              self.shutdown_event)
                self.appli.repo.start_looping_tasks()
        self.set_url_rewriter()
        CW_EVENT_MANAGER.bind('after-registry-reload', self.set_url_rewriter)

    def start_service(self):
        start_task(self.appli.session_handler.clean_sessions_interval,
                   self.appli.session_handler.clean_sessions)

    def set_url_rewriter(self):
        self.url_rewriter = self.appli.vreg['components'].select_or_none('urlrewriter')

    def shutdown_event(self):
        """callback fired when the server is shutting down to properly
        clean opened sessions
        """
        self.appli.repo.shutdown()

    def pyro_loop_event(self):
        """listen for pyro events"""
        try:
            self.pyro_daemon.handleRequests(self.pyro_listen_timeout)
        except select.error:
            return

    def getChild(self, path, request):
        """Indicate which resource to use to process down the URL's path"""
        return self

    def render(self, request):
        """Render a page from the root resource"""
        # reload modified files in debug mode
        if self.config.debugmode:
            self.config.uiprops.reload_if_needed()
            if self.https_url:
                self.config.https_uiprops.reload_if_needed()
            self.appli.vreg.reload_if_needed()
        if self.config['profile']: # default profiler don't trace threads
            return self.render_request(request)
        else:
            deferred = threads.deferToThread(self.render_request, request)
            return NOT_DONE_YET

    def render_request(self, request):
        try:
            # processing HUGE files (hundred of megabytes) in http.processReceived
            # blocks other HTTP requests processing
            # due to the clumsy & slow parsing algorithm of cgi.FieldStorage
            # so we deferred that part to the cubicweb thread
            request.process_multipart()
            return self._render_request(request)
        except Exception:
            trace = traceback.format_exc()
            return HTTPResponse(stream='<pre>%s</pre>' % xml_escape(trace),
                                code=500, twisted_request=request)

    def _render_request(self, request):
        origpath = request.path
        host = request.host
        # dual http/https access handling: expect a rewrite rule to prepend
        # 'https' to the path to detect https access
        https = False
        if origpath.split('/', 2)[1] == 'https':
            origpath = origpath[6:]
            request.uri = request.uri[6:]
            https = True
        if self.url_rewriter is not None:
            # XXX should occur before authentication?
            path = self.url_rewriter.rewrite(host, origpath, request)
            request.uri.replace(origpath, path, 1)
        else:
            path = origpath
        req = CubicWebTwistedRequestAdapter(request, self.appli.vreg, https)
        try:
            ### Try to generate the actual request content
            content = self.appli.handle_request(req, path)
        except DirectResponse as ex:
            return ex.response
        # at last: create twisted object
        return HTTPResponse(code    = req.status_out,
                            headers = req.headers_out,
                            stream  = content,
                            twisted_request=req._twreq)

    # these are overridden by set_log_methods below
    # only defining here to prevent pylint from complaining
    @classmethod
    def debug(cls, msg, *a, **kw):
        pass
    info = warning = error = critical = exception = debug


JSON_PATHS = set(('json',))
FRAME_POST_PATHS = set(('validateform',))

orig_gotLength = http.Request.gotLength
@monkeypatch(http.Request)
def gotLength(self, length):
    orig_gotLength(self, length)
    if length > MAX_POST_LENGTH: # length is 0 on GET
        path = self.channel._path.split('?', 1)[0].rstrip('/').rsplit('/', 1)[-1]
        self.clientproto = 'HTTP/1.1' # not yet initialized
        self.channel.persistent = 0   # force connection close on cleanup
        self.setResponseCode(http.BAD_REQUEST)
        if path in JSON_PATHS: # XXX better json path detection
            self.setHeader('content-type',"application/json")
            body = json_dumps({'reason': 'request max size exceeded'})
        elif path in FRAME_POST_PATHS: # XXX better frame post path detection
            self.setHeader('content-type',"text/html")
            body = ('<script type="text/javascript">'
                    'window.parent.handleFormValidationResponse(null, null, null, %s, null);'
                    '</script>' % json_dumps( (False, 'request max size exceeded', None) ))
        else:
            self.setHeader('content-type',"text/html")
            body = ("<html><head><title>Processing Failed</title></head><body>"
                    "<b>request max size exceeded</b></body></html>")
        self.setHeader('content-length', str(len(body)))
        self.write(body)
        # see request.finish(). Done here since we get error due to not full
        # initialized request
        self.finished = 1
        if not self.queued:
            self._cleanup()
        for d in self.notifications:
            d.callback(None)
        self.notifications = []

@monkeypatch(http.Request)
def requestReceived(self, command, path, version):
    """Called by channel when all data has been received.

    This method is not intended for users.
    """
    self.content.seek(0, 0)
    self.args = {}
    self.files = {}
    self.stack = []
    self.method, self.uri = command, path
    self.clientproto = version
    x = self.uri.split('?', 1)
    if len(x) == 1:
        self.path = self.uri
    else:
        self.path, argstring = x
        self.args = http.parse_qs(argstring, 1)
    # cache the client and server information, we'll need this later to be
    # serialized and sent with the request so CGIs will work remotely
    self.client = self.channel.transport.getPeer()
    self.host = self.channel.transport.getHost()
    # Argument processing
    ctype = self.getHeader('content-type')
    self._do_process_multipart = False
    if self.method == "POST" and ctype:
        key, pdict = parse_header(ctype)
        if key == 'application/x-www-form-urlencoded':
            self.args.update(http.parse_qs(self.content.read(), 1))
        elif key == 'multipart/form-data':
            # defer this as it can be extremely time consumming
            # with big files
            self._do_process_multipart = True
    self.process()


@monkeypatch(http.Request)
def process_multipart(self):
    if not self._do_process_multipart:
        return
    form = FieldStorage(self.content, self.received_headers,
                        environ={'REQUEST_METHOD': 'POST'},
                        keep_blank_values=1,
                        strict_parsing=1)
    for key in form:
        value = form[key]
        if isinstance(value, list):
            self.args[key] = [v.value for v in value]
        elif value.filename:
            if value.done != -1: # -1 is transfer has been interrupted
                self.files[key] = (value.filename, value.file)
            else:
                self.files[key] = (None, None)
        else:
            self.args[key] = value.value

from logging import getLogger
from cubicweb import set_log_methods
LOGGER = getLogger('cubicweb.twisted')
set_log_methods(CubicWebRootResource, LOGGER)

def run(config, vreg=None, debug=None):
    if debug is not None:
        config.debugmode = debug
    config.check_writeable_uid_directory(config.appdatahome)
    # create the site
    root_resource = CubicWebRootResource(config, vreg=vreg)
    website = server.Site(root_resource)
    # serve it via standard HTTP on port set in the configuration
    port = config['port'] or 8080
    interface = config['interface']
    reactor.suggestThreadPoolSize(config['webserver-threadpool-size'])
    reactor.listenTCP(port, website, interface=interface)
    if not config.debugmode:
        if sys.platform == 'win32':
            raise ConfigurationError("Under windows, you must use the service management "
                                     "commands (e.g : 'net start my_instance)'")
        from logilab.common.daemon import daemonize
        LOGGER.info('instance started in the background on %s', root_resource.base_url)
        whichproc = daemonize(config['pid-file'], umask=config['umask'])
        if whichproc: # 1 = orig process, 2 = first fork, None = second fork (eg daemon process)
            return whichproc # parent process
    root_resource.init_publisher() # before changing uid
    if config['uid'] is not None:
        from logilab.common.daemon import setugid
        setugid(config['uid'])
    root_resource.start_service()
    LOGGER.info('instance started on %s', root_resource.base_url)
    # avoid annoying warnign if not in Main Thread
    signals = threading.currentThread().getName() == 'MainThread'
    if config['profile']:
        import cProfile
        cProfile.runctx('reactor.run(installSignalHandlers=%s)' % signals,
                        globals(), locals(), config['profile'])
    else:
        reactor.run(installSignalHandlers=signals)