Python DBCache.gethostname方法代碼示例

# 需要導入模塊: from database import DBCache [as 別名]
# 或者: from database.DBCache import gethostname [as 別名]

#.........這裏部分代碼省略.........
        if backend is None:
            # no backend given, use master
            self.host = self.db.settings.NULL.MasterServerIP
            self.hostname = self.db._gethostfromaddr(self.host)

        else:
            backend = backend.strip('[]')
            query = "SELECT hostname FROM settings WHERE value=? AND data=?"
            if self._reip.match(backend):
                # given backend is IP address
                self.host = backend
                self.hostname = self.db._gethostfromaddr(
                                            backend, 'BackendServerIP')
            elif check_ipv6(backend):
                # given backend is IPv6 address
                self.host = backend
                self.hostname = self.db._gethostfromaddr(
                                            backend, 'BackendServerIP6')
            else:
                # given backend is hostname, pull address from database
                self.hostname = backend
                self.host = self.db._getpreferredaddr(backend)

        # lookup port from database
        self.port = int(self.db.settings[self.hostname].BackendServerPort)
        if not self.port:
            raise MythDBError(MythError.DB_SETTING, 'BackendServerPort',
                                            self.port)

        self._ident = '%s:%d' % (self.host, self.port)
        if self._ident in self._shared:
            # existing connection found
            self._conn = self._shared[self._ident]
            if self.sendcommands:
                if self._conn.command is None:
                    self._conn.command = self._newcmdconn()
                elif self.blockshutdown:
                    # upref block of shutdown
                    # issue command to backend if needed
                    self._conn.blockshutdown += 1
                    if self._conn.blockshutdown == 1:
                        self._conn.command.blockShutdown()
            if self.receiveevents:
                if self._conn.event is None:
                    self._conn.event = self._neweventconn()
        else:
            # no existing connection, create new
            self._conn = self._ConnHolder()

            if self.sendcommands:
                self._conn.command = self._newcmdconn()
                if self.blockshutdown:
                    self._conn.blockshutdown = 1
            if self.receiveevents:
                self._conn.event = self._neweventconn()

            self._shared[self._ident] = self._conn

        self._events = self._listhandlers()
        for func in self._events:
            self.registerevent(func)

    def __del__(self):
        # downref block of shutdown
        # issue command to backend if needed
        #print 'destructing BECache'
        if self.blockshutdown:
            self._conn.blockshutdown -= 1
            if not self._conn.blockshutdown:
                self._conn.command.unblockShutdown()

    def _newcmdconn(self):
        return BEConnection(self.host, self.port, self.db.gethostname(),
                            self.blockshutdown)

    def _neweventconn(self):
        return BEEventConnection(self.host, self.port, self.db.gethostname())

    def backendCommand(self, data):
        """
        obj.backendCommand(data) -> response string

        Sends a formatted command via a socket to the mythbackend.
        """
        if self._conn.command is None:
            return ""
        return self._conn.command.backendCommand(data)

    def _listhandlers(self):
        return []

    def registerevent(self, func, regex=None):
        if self._conn.event is None:
            return
        if regex is None:
            regex = func()
        self._conn.event.registerevent(regex, func)

    def clearevents(self):
        self._events = []

# 需要導入模塊: from database import DBCache [as 別名]
# 或者: from database.DBCache import gethostname [as 別名]
class BECache( SplitInt ):
    """
    BECache(backend=None, noshutdown=False, db=None)
                                            -> MythBackend connection object

    Basic class for mythbackend socket connections.
    Offers connection caching to prevent multiple connections.

    'backend' allows a hostname or IP address to connect to. If not provided,
                connect will be made to the master backend. Port is always
                taken from the database.
    'db' allows an existing database object to be supplied.
    'noshutdown' specified whether the backend will be allowed to go into
                automatic shutdown while the connection is alive.

    Available methods:
        joinInt()           - convert two signed ints to one 64-bit
                              signed int
        splitInt()          - convert one 64-bit signed int to two
                              signed ints
        backendCommand()    - Sends a formatted command to the backend
                              and returns the response.
    """
    logmodule = 'Python Backend Connection'
    _shared = weakref.WeakValueDictionary()
    _reip = re.compile('(?:\d{1,3}\.){3}\d{1,3}')

    def __repr__(self):
        return "<%s 'myth://%s:%d/' at %s>" % \
                (str(self.__class__).split("'")[1].split(".")[-1],
                 self.hostname, self.port, hex(id(self)))

    def __init__(self, backend=None, noshutdown=False, db=None, opts=None):
        self.db = DBCache(db)
        self.log = MythLog(self.logmodule, db=self.db)
        self.hostname = None

        if opts is None:
            self.opts = BEConnection.BEConnOpts(noshutdown)
        else:
            self.opts = opts

        if backend is None:
            # no backend given, use master
            self.host = self.db.settings.NULL.MasterServerIP

        else:
            if self._reip.match(backend):
                # given backend is IP address
                self.host = backend
            else:
                # given backend is hostname, pull address from database
                self.hostname = backend
                self.host = self.db.settings[backend].BackendServerIP
                if not self.host:
                    raise MythDBError(MythError.DB_SETTING,
                                            'BackendServerIP', backend)

        if self.hostname is None:
            # reverse lookup hostname from address
            with self.db.cursor(self.log) as cursor:
                if cursor.execute("""SELECT hostname FROM settings
                                     WHERE value='BackendServerIP'
                                     AND data=?""", [self.host]) == 0:
                    # no match found
                    raise MythDBError(MythError.DB_SETTING, 'BackendServerIP',
                                            self.host)
                self.hostname = cursor.fetchone()[0]

        # lookup port from database
        self.port = int(self.db.settings[self.hostname].BackendServerPort)
        if not self.port:
            raise MythDBError(MythError.DB_SETTING, 'BackendServerPort',
                                            self.port)

        self._uuid = uuid4()
        self._ident = '%s:%d' % (self.host, self.port)
        if self._ident in self._shared:
            # existing connection found
            # register and reconnect if necessary
            self.be = self._shared[self._ident]
            self.be.registeruser(self._uuid, self.opts)
            self.be.reconnect()
        else:
            # no existing connection, create new
            self.be = BEConnection(self.host, self.port, \
                                    self.db.gethostname(), self.opts)
            self.be.registeruser(self._uuid, self.opts)
            self._shared[self._ident] = self.be

    def backendCommand(self, data):
        """
        obj.backendCommand(data) -> response string

        Sends a formatted command via a socket to the mythbackend.
        """
        return self.be.backendCommand(data)