Helpviewer/Network/NetworkAccessManager.py

# -*- coding: utf-8 -*-

# Copyright (c) 2009 - 2013 Detlev Offenbach <detlev@die-offenbachs.de>
#

"""
Module implementing a QNetworkAccessManager subclass.
"""

import os

from PyQt4.QtCore import pyqtSignal, QByteArray, qVersion
from PyQt4.QtGui import QDialog
from PyQt4.QtNetwork import QNetworkAccessManager, QNetworkRequest, QNetworkReply

from E5Network.E5NetworkProxyFactory import E5NetworkProxyFactory, \
    proxyAuthenticationRequired
try:
    from PyQt4.QtNetwork import QSslSocket
    from E5Network.E5SslErrorHandler import E5SslErrorHandler
    SSL_AVAILABLE = True
except ImportError:
    SSL_AVAILABLE = False

import Preferences
import Utilities


class NetworkAccessManager(QNetworkAccessManager):
    """
    Class implementing a QNetworkAccessManager subclass.
    
    @signal requestCreated(QNetworkAccessManager.Operation, QNetworkRequest, QNetworkReply)
        emitted after the request has been created
    """
    requestCreated = pyqtSignal(
        QNetworkAccessManager.Operation, QNetworkRequest, QNetworkReply)
    
    def __init__(self, engine, parent=None):
        """
        Constructor
        
        @param engine reference to the help engine (QHelpEngine)
        @param parent reference to the parent object (QObject)
        """
        super().__init__(parent)
        
        self.__adblockNetwork = None
        
        self.__schemeHandlers = {}  # dictionary of scheme handlers
        
        self.__proxyFactory = E5NetworkProxyFactory()
        self.setProxyFactory(self.__proxyFactory)
        
        self.__setDiskCache()
        self.languagesChanged()
        
        if SSL_AVAILABLE:
            self.__sslErrorHandler = E5SslErrorHandler(self)
            self.sslErrors.connect(self.__sslErrorHandler.sslErrorsReplySlot)
        
        self.proxyAuthenticationRequired.connect(proxyAuthenticationRequired)
        self.authenticationRequired.connect(self.__authenticationRequired)
        
        self.__doNotTrack = Preferences.getHelp("DoNotTrack")
        self.__sendReferer = Preferences.getHelp("SendReferer")
        
        # register scheme handlers
        if engine:
            from .QtHelpAccessHandler import QtHelpAccessHandler
            self.setSchemeHandler("qthelp", QtHelpAccessHandler(engine, self))
        
        from .EricAccessHandler import EricAccessHandler
        self.setSchemeHandler("eric", EricAccessHandler(self))
        
        from .AboutAccessHandler import AboutAccessHandler
        self.setSchemeHandler("about", AboutAccessHandler(self))
        
        from Helpviewer.AdBlock.AdBlockAccessHandler import AdBlockAccessHandler
        self.setSchemeHandler("abp", AdBlockAccessHandler(self))
        
        from .FtpAccessHandler import FtpAccessHandler
        self.setSchemeHandler("ftp", FtpAccessHandler(self))
        
        from .FileAccessHandler import FileAccessHandler
        self.setSchemeHandler("file", FileAccessHandler(self))
    
    def setSchemeHandler(self, scheme, handler):
        """
        Public method to register a scheme handler.
        
        @param scheme access scheme (string)
        @param handler reference to the scheme handler object (SchemeAccessHandler)
        """
        self.__schemeHandlers[scheme] = handler
    
    def createRequest(self, op, request, outgoingData=None):
        """
        Protected method to create a request.
        
        @param op the operation to be performed (QNetworkAccessManager.Operation)
        @param request reference to the request object (QNetworkRequest)
        @param outgoingData reference to an IODevice containing data to be sent
            (QIODevice)
        @return reference to the created reply object (QNetworkReply)
        """
        scheme = request.url().scheme()
        if scheme == "https" and (not SSL_AVAILABLE or not QSslSocket.supportsSsl()):
            from .NetworkProtocolUnknownErrorReply import NetworkProtocolUnknownErrorReply
            return NetworkProtocolUnknownErrorReply(scheme, self)
        
        import Helpviewer.HelpWindow
        
        if op == QNetworkAccessManager.PostOperation and outgoingData is not None:
            outgoingDataByteArray = outgoingData.peek(1024 * 1024)
            Helpviewer.HelpWindow.HelpWindow.passwordManager().post(
                request, outgoingDataByteArray)
        
        reply = None
        if scheme in self.__schemeHandlers:
            reply = self.__schemeHandlers[scheme]\
                        .createRequest(op, request, outgoingData)
        if reply is not None:
            return reply
        
        # give GreaseMonkey the chance to create a request
        reply = Helpviewer.HelpWindow.HelpWindow.greaseMonkeyManager().createRequest(
            op, request, outgoingData)
        if reply is not None:
            return reply
        
        req = QNetworkRequest(request)
        if req.rawHeader("X-Eric5-UserLoadAction") == QByteArray("1"):
            req.setRawHeader("X-Eric5-UserLoadAction", QByteArray())
            req.setAttribute(QNetworkRequest.User + 200, "")
        else:
            req.setAttribute(QNetworkRequest.User + 200, req.rawHeader("Referer"))
        
        if hasattr(QNetworkRequest, 'HttpPipeliningAllowedAttribute'):
            req.setAttribute(QNetworkRequest.HttpPipeliningAllowedAttribute, True)
        if not self.__acceptLanguage.isEmpty():
            req.setRawHeader("Accept-Language", self.__acceptLanguage)
        
        # AdBlock code
        if op == QNetworkAccessManager.GetOperation:
            if self.__adblockNetwork is None:
                self.__adblockNetwork = \
                    Helpviewer.HelpWindow.HelpWindow.adBlockManager().network()
            reply = self.__adblockNetwork.block(req)
            if reply is not None:
                reply.setParent(self)
                return reply
        
        # set cache policy
        if op == QNetworkAccessManager.GetOperation:
            urlHost = req.url().host()
            for host in Preferences.getHelp("NoCacheHosts"):
                if host in urlHost:
                    req.setAttribute(QNetworkRequest.CacheLoadControlAttribute,
                        QNetworkRequest.AlwaysNetwork)
                    break
            else:
                req.setAttribute(QNetworkRequest.CacheLoadControlAttribute,
                    Preferences.getHelp("CachePolicy"))
        else:
            req.setAttribute(QNetworkRequest.CacheLoadControlAttribute,
                QNetworkRequest.AlwaysNetwork)
        
        # Do Not Track feature
        if self.__doNotTrack:
            req.setRawHeader("DNT", "1")
        
        # Send referer header?
        if not self.__sendReferer and \
           req.url().host() not in Preferences.getHelp("SendRefererWhitelist"):
            req.setRawHeader("Referer", "")
        
        reply = QNetworkAccessManager.createRequest(self, op, req, outgoingData)
        self.requestCreated.emit(op, req, reply)
        
        return reply
    
    def __authenticationRequired(self, reply, auth):
        """
        Private slot to handle an authentication request.
        
        @param reply reference to the reply object (QNetworkReply)
        @param auth reference to the authenticator object (QAuthenticator)
        """
        urlRoot = "{0}://{1}"\
            .format(reply.url().scheme(), reply.url().authority())
        realm = auth.realm()
        if not realm and 'realm' in auth.options():
            realm = auth.option("realm")
        if realm:
            info = self.trUtf8("<b>Enter username and password for '{0}', "
                               "realm '{1}'</b>").format(urlRoot, realm)
        else:
            info = self.trUtf8("<b>Enter username and password for '{0}'</b>")\
                .format(urlRoot)
        
        from UI.AuthenticationDialog import AuthenticationDialog
        import Helpviewer.HelpWindow
        
        dlg = AuthenticationDialog(info, auth.user(),
                                   Preferences.getUser("SavePasswords"),
                                   Preferences.getUser("SavePasswords"))
        if Preferences.getUser("SavePasswords"):
            username, password = \
                Helpviewer.HelpWindow.HelpWindow.passwordManager().getLogin(
                    reply.url(), realm)
            if username:
                dlg.setData(username, password)
        if dlg.exec_() == QDialog.Accepted:
            username, password = dlg.getData()
            auth.setUser(username)
            auth.setPassword(password)
            if Preferences.getUser("SavePasswords"):
                Helpviewer.HelpWindow.HelpWindow.passwordManager().setLogin(
                    reply.url(), realm, username, password)
    
    def preferencesChanged(self):
        """
        Public slot to signal a change of preferences.
        """
        self.__setDiskCache()
        
        self.__doNotTrack = Preferences.getHelp("DoNotTrack")
        self.__sendReferer = Preferences.getHelp("SendReferer")
    
    def languagesChanged(self):
        """
        Public slot to (re-)load the list of accepted languages.
        """
        from Helpviewer.HelpLanguagesDialog import HelpLanguagesDialog
        languages = Preferences.toList(
            Preferences.Prefs.settings.value("Help/AcceptLanguages",
                HelpLanguagesDialog.defaultAcceptLanguages()))
        self.__acceptLanguage = HelpLanguagesDialog.httpString(languages)
    
    def __setDiskCache(self):
        """
        Private method to set the disk cache.
        """
        if Preferences.getHelp("DiskCacheEnabled"):
            from PyQt4.QtWebKit import qWebKitVersion
            from .NetworkDiskCache import NetworkDiskCache
            diskCache = NetworkDiskCache(self)
            location = os.path.join(Utilities.getConfigDir(), "browser", 'cache',
                                    "{0}-Qt{1}".format(qWebKitVersion(), qVersion()))
            size = Preferences.getHelp("DiskCacheSize") * 1024 * 1024
            diskCache.setCacheDirectory(location)
            diskCache.setMaximumCacheSize(size)
        else:
            diskCache = None
        self.setCache(diskCache)