Source code for txmongo.connection

# Copyright 2009-2015 The TxMongo Developers. All rights reserved.
# Use of this source code is governed by the Apache License that can be
# found in the LICENSE file.

from __future__ import absolute_import, division

from bson.codec_options import DEFAULT_CODEC_OPTIONS
from pymongo.errors import AutoReconnect, ConfigurationError, OperationFailure
from pymongo.uri_parser import parse_uri
from pymongo.read_preferences import ReadPreference
from pymongo.write_concern import WriteConcern
from twisted.internet import defer, reactor, task
from twisted.internet.protocol import ReconnectingClientFactory, ClientFactory
from twisted.python import log
from twisted.python.compat import StringType
from txmongo.database import Database
from txmongo.protocol import MongoProtocol, Query
from txmongo.utils import timeout



class _Connection(ReconnectingClientFactory):
    __notify_ready = None
    __allnodes = None
    __index = -1
    __uri = None

    instance = None
    protocol = MongoProtocol

    def __init__(self, pool, uri, connection_id, initial_delay, max_delay):
        self.__allnodes = list(uri["nodelist"])
        self.__notify_ready = []
        self.__pool = pool
        self.__uri = uri
        self.connection_id = connection_id
        self.initialDelay = initial_delay
        self.maxDelay = max_delay
        self.__auth_creds = {}

    def buildProtocol(self, addr):
        # Build the protocol.
        p = ReconnectingClientFactory.buildProtocol(self, addr)
        return p

    def _initializeProto(self, proto):
        yield proto.connectionReady()

        uri_options = self.uri['options']
        slaveok = uri_options.get('slaveok', False)
        if 'readpreference' in uri_options:
            slaveok = uri_options['readpreference'] not in _PRIMARY_READ_PREFERENCES

            if not slaveok:
                # Update our server configuration. This may disconnect if the node
                # is not a master.
                yield self.configure(proto)

            yield self._auth_proto(proto)
        except Exception as e:

    def __send_ismaster(proto, **kwargs):
        query = Query(collection="admin.$cmd", query={"ismaster": 1})
        return proto.send_QUERY(query)

    def configure(self, proto):
            Configures the protocol using the information gathered from the
            remote Mongo instance. Such information may contain the max
            BSON document size, replica set configuration, and the master
            status of the instance.

        if not proto:

        reply = yield self.__send_ismaster(proto, timeout=self.initialDelay)

        # Handle the reply from the "ismaster" query. The reply contains
        # configuration information about the peer.

        # Make sure we got a result document.
        if len(reply.documents) != 1:
            raise OperationFailure("TxMongo: invalid document length.")

        # Get the configuration document from the reply.
        config = reply.documents[0].decode()

        # Make sure the command was successful.
        if not config.get("ok"):
            code = config.get("code")
            msg = "TxMongo: " + config.get("err", "Unknown error")
            raise OperationFailure(msg, code)

        # Check that the replicaSet matches.
        set_name = config.get("setName")
        expected_set_name = self.uri["options"].get("replicaset")
        if expected_set_name and (expected_set_name != set_name):
            # Log the invalid replica set failure.
            msg = "TxMongo: Mongo instance does not match requested replicaSet."
            raise ConfigurationError(msg)

        # Track max bson object size limit.
        proto.max_bson_size = config.get("maxBsonObjectSize", DEFAULT_MAX_BSON_SIZE)
        proto.max_write_batch_size = config.get("maxWriteBatchSize", DEFAULT_MAX_WRITE_BATCH_SIZE)

        proto.set_wire_versions(config.get("minWireVersion", 0),
                                config.get("maxWireVersion", 0))

        # Track the other hosts in the replica set.
        hosts = config.get("hosts")
        if isinstance(hosts, list) and hosts:
            for host in hosts:
                if ':' not in host:
                    host = (host, 27017)
                    host = host.split(':', 1)
                    host[1] = int(host[1])
                    host = tuple(host)
                if host not in self.__allnodes:

        # Check if this node is the master.
        ismaster = config.get("ismaster")
        if not ismaster:
            msg = "TxMongo: MongoDB host `%s` is not master." % config.get('me')
            raise AutoReconnect(msg)

    def clientConnectionFailed(self, connector, reason):
        self.instance = None
        if self.continueTrying:
            self.connector = connector

    def clientConnectionLost(self, connector, reason):
        self.instance = None
        if self.continueTrying:
            self.connector = connector

    def notifyReady(self):
            Returns a deferred that will fire when the factory has created a
            protocol that can be used to communicate with a Mongo server.

            Note that this will not fire until we have connected to a Mongo
            master, unless slaveOk was specified in the Mongo URI connection
        if self.instance:
            return defer.succeed(self.instance)

        def on_cancel(d):

        df = defer.Deferred(on_cancel)
        return df

    def retryNextHost(self, connector=None):
            Have this connector connect again, to the next host in the
            configured list of hosts.
        if not self.continueTrying:
            msg = "TxMongo: Abandoning {0} on explicit request.".format(connector)

        if connector is None:
            if self.connector is None:
                raise ValueError("TxMongo: No additional connector to retry.")
                connector = self.connector

        delay = False
        self.__index += 1

        if self.__index >= len(self.__allnodes):
            self.__index = 0
            delay = True, connector.port = self.__allnodes[self.__index]

        if delay:

    def setInstance(self, instance=None, reason=None):
        if instance == self.instance:
            # Should not fail deferreds from __notify_ready if setInstance(None)
            # called when instance is already None
        self.instance = instance
        deferreds, self.__notify_ready = self.__notify_ready, []
        if deferreds:
            for df in deferreds:
                if instance:

    def uri(self):
        return self.__uri

    def _auth_proto(self, proto):
        return defer.DeferredList(
            [proto.authenticate(database, username, password, mechanism)
             for database, (username, password, mechanism) in self.__auth_creds.items()],

    def authenticate(self, database, username, password, mechanism):
        self.__auth_creds[str(database)] = (username, password, mechanism)

        if self.instance:
            return self.instance.authenticate(database, username, password, mechanism)
            return defer.succeed(None)

[docs]class ConnectionPool(object): __index = 0 __pool = None __pool_size = None __uri = None __wc_possible_options = {'w', "wtimeout", 'j', "fsync"} __pinger_discovery_interval = 10 def __init__(self, uri="mongodb://", pool_size=1, ssl_context_factory=None, ping_interval=10, ping_timeout=10, **kwargs): assert isinstance(uri, StringType) assert isinstance(pool_size, int) assert pool_size >= 1 if not uri.startswith("mongodb://"): uri = "mongodb://" + uri self.__uri = parse_uri(uri) wc_options = self.__uri['options'].copy() wc_options.update(kwargs) wc_options = dict((k, v) for k, v in wc_options.items() if k in self.__wc_possible_options) self.__write_concern = WriteConcern(**wc_options) self.__codec_options = kwargs.get('codec_options', DEFAULT_CODEC_OPTIONS) retry_delay = kwargs.get('retry_delay', 1.0) max_delay = kwargs.get('max_delay', 60.0) self.__pool_size = pool_size self.__pool = [ _Connection(self, self.__uri, i, retry_delay, max_delay) for i in range(pool_size) ] if self.__uri['database'] and self.__uri['username'] and self.__uri['password']: auth_db = self.__uri['options'].get('authsource') or self.__uri['database'] self.authenticate(auth_db, self.__uri['username'], self.__uri['password'], self.__uri['options'].get('authmechanism', 'DEFAULT')) host, port = self.__uri['nodelist'][0] self.ssl_context_factory = ssl_context_factory initial_delay = kwargs.get('retry_delay', 30) for factory in self.__pool: factory.connector = self.__tcp_or_ssl_connect(host, port, factory, timeout=initial_delay) self.ping_interval = ping_interval self.ping_timeout = ping_timeout self.__pingers = {} self.__pinger_discovery = task.LoopingCall(self.__discovery_nodes_to_ping) self.__pinger_discovery.start(self.__pinger_discovery_interval, now=False) def __tcp_or_ssl_connect(self, host, port, factory, **kwargs): if self.ssl_context_factory: return reactor.connectSSL(host, port, factory, self.ssl_context_factory, **kwargs) else: return reactor.connectTCP(host, port, factory, **kwargs) @property def write_concern(self): return self.__write_concern @property def codec_options(self): return self.__codec_options
[docs] def getprotocols(self): return self.__pool
def __getitem__(self, name): return Database(self, name) def __getattr__(self, name): return self[name] def __repr__(self): if self.uri["nodelist"]: return "Connection(%r, %r)" % self.uri["nodelist"][0] return "Connection()"
[docs] def get_default_database(self): if self.uri["database"]: return self[self.uri["database"]] else: return None
[docs] def drop_database(self, name_or_database): if isinstance(name_or_database, (bytes, StringType)): db = self[name_or_database] elif isinstance(name_or_database, Database): db = name_or_database else: raise TypeError("argument to drop_database() should be database name " "or database object") return db.command("dropDatabase")
[docs] def disconnect(self): self.__pinger_discovery.stop() for pinger in self.__pingers.values(): pinger.connector.disconnect() for factory in self.__pool: factory.stopTrying() factory.stopFactory() if factory.instance and factory.instance.transport: factory.instance.transport.loseConnection() if factory.connector: factory.connector.disconnect() # Wait for the next iteration of the loop for resolvers # to potentially cleanup. df = defer.Deferred() reactor.callLater(0, df.callback, None) return df
[docs] def authenticate(self, database, username, password, mechanism="DEFAULT"): def fail(failure): failure.trap(defer.FirstError) raise failure.value.subFailure.value return defer.gatherResults( [connection.authenticate(database, username, password, mechanism) for connection in self.__pool], consumeErrors=True ).addErrback(fail)
[docs] def getprotocol(self): # Get the next protocol available for communication in the pool. connection = self.__pool[self.__index] self.__index = (self.__index + 1) % self.__pool_size # If the connection is already connected, just return it. if connection.instance: return defer.succeed(connection.instance) # Wait for the connection to connection. return connection.notifyReady().addCallback(lambda conn: conn.instance)
@property def uri(self): return self.__uri # Pingers are persistent connections that are established to each # node of the replicaset to monitor their availability. # # Every `__pinger_discovery_interval` seconds ConnectionPool compares # actual nodes addresses and starts/stops Pingers to ensure that # Pinger is started for every node address. # # Every `ping_interval` seconds pingers send ismaster commands. # # All pool connections to corresponding TCP address are dropped # if one of following happens: # 1. Pinger is unable to receive response to ismaster within # `ping_timeout` seconds # 2. Pinger is unable to connect to address within `ping_timeout` # seconds # # If Pinger's connection is closed by server, pool connections are not # dropped. Next discovery procedure will recreate the Pinger. def __discovery_nodes_to_ping(self): existing = set(self.__pingers) peers = {conn.instance.transport.getPeer() for conn in self.__pool if conn.instance} for peer in peers - existing: pinger = _Pinger(self.ping_interval, self.ping_timeout, self.__on_ping_lost, self.__on_ping_fail) pinger.connector = self.__tcp_or_ssl_connect(, peer.port, pinger, timeout=self.ping_timeout) self.__pingers[peer] = pinger for unused_peer in existing - peers: self.__pingers[unused_peer].connector.disconnect() del self.__pingers[unused_peer] def __on_ping_lost(self, addr): if addr in self.__pingers: self.__pingers[addr].connector.disconnect() del self.__pingers[addr] def __on_ping_fail(self, addr): # Kill all pool connections to this addr for connection in self.__pool: if connection.instance and connection.instance.transport.getPeer() == addr: connection.instance.transport.abortConnection() self.__on_ping_lost(addr)
class _PingerProtocol(MongoProtocol): __next_call = None def __init__(self, interval, timeout, fail_callback): MongoProtocol.__init__(self) self.interval = interval self.timeout = timeout self.fail_callback = fail_callback def ping(self): def on_ok(result): if timeout_call.cancel() self.__next_call = reactor.callLater(self.interval, def on_fail(failure): if timeout_call.cancel() on_timeout() def on_timeout(): self.transport.loseConnection() self.fail_callback(self.transport.getPeer()) timeout_call = reactor.callLater(self.timeout, on_timeout) self.send_QUERY(Query(collection="admin.$cmd", query={"ismaster": 1}))\ .addCallbacks(on_ok, on_fail) def connectionMade(self): MongoProtocol.connectionMade(self) def connectionLost(self, reason): MongoProtocol.connectionLost(self, reason) if self.__next_call and self.__next_call.cancel() class _Pinger(ClientFactory): def __init__(self, interval, timeout, lost_callback, fail_callback): self.interval = interval self.timeout = timeout self.lost_callback = lost_callback self.fail_callback = fail_callback def buildProtocol(self, addr): proto = _PingerProtocol(self.interval, self.timeout, self.fail_callback) proto.factory = self return proto def setInstance(self, instance=None, reason=None): pass def clientConnectionLost(self, connector, reason): self.lost_callback(connector.getDestination()) def clientConnectionFailed(self, connector, reason): self.fail_callback(connector.getDestination()) ### # Begin Legacy Wrapper ###
[docs]class MongoConnection(ConnectionPool): def __init__(self, host="", port=27017, pool_size=1, **kwargs): uri = "mongodb://%s:%d/" % (host, port) ConnectionPool.__init__(self, uri, pool_size=pool_size, **kwargs)
lazyMongoConnectionPool = MongoConnection lazyMongoConnection = MongoConnection MongoConnectionPool = MongoConnection ### # End Legacy Wrapper ###