Python util.ReentrantTimer类代码示例

    def __init__(self, client, group, topic, partitions=None, auto_commit=True,
                 auto_commit_every_n=AUTO_COMMIT_MSG_COUNT,
                 auto_commit_every_t=AUTO_COMMIT_INTERVAL):

        self.client = client
        self.topic = topic
        self.group = group
        self.client.load_metadata_for_topics(topic)
        self.offsets = {}

        if not partitions:
            partitions = self.client.get_partition_ids_for_topic(topic)
        else:
            assert all(isinstance(x, numbers.Integral) for x in partitions)

        # Variables for handling offset commits
        self.commit_lock = Lock()
        self.commit_timer = None
        self.count_since_commit = 0
        self.auto_commit = auto_commit
        self.auto_commit_every_n = auto_commit_every_n
        self.auto_commit_every_t = auto_commit_every_t

        # Set up the auto-commit timer
        if auto_commit is True and auto_commit_every_t is not None:
            self.commit_timer = ReentrantTimer(auto_commit_every_t,
                                               self.commit)
            self.commit_timer.start()

        if auto_commit:
            self.fetch_last_known_offsets(partitions)
        else:
            for partition in partitions:
                self.offsets[partition] = 0

    def __init__(self, client, group, topic, partitions=None, auto_commit=True,
                 auto_commit_every_n=AUTO_COMMIT_MSG_COUNT,
                 auto_commit_every_t=AUTO_COMMIT_INTERVAL):

        self.client = client
        self.topic = topic
        self.group = group
        self.client._load_metadata_for_topics(topic)
        self.offsets = {}

        if not partitions:
            partitions = self.client.topic_partitions[topic]

        # Variables for handling offset commits
        self.commit_lock = Lock()
        self.commit_timer = None
        self.count_since_commit = 0
        self.auto_commit = auto_commit
        self.auto_commit_every_n = auto_commit_every_n
        self.auto_commit_every_t = auto_commit_every_t

        # Set up the auto-commit timer
        if auto_commit is True and auto_commit_every_t is not None:
            self.commit_timer = ReentrantTimer(auto_commit_every_t,
                                               self.commit)
            self.commit_timer.start()

        def get_or_init_offset_callback(resp):
            if resp.error == ErrorMapping.NO_ERROR:
                return resp.offset
            elif resp.error == ErrorMapping.UNKNOWN_TOPIC_OR_PARTITON:
                return 0
            else:
                raise Exception("OffsetFetchRequest for topic=%s, "
                                "partition=%d failed with errorcode=%s" % (
                                    resp.topic, resp.partition, resp.error))

        # Uncomment for 0.8.1
        #
        #for partition in partitions:
        #    req = OffsetFetchRequest(topic, partition)
        #    (offset,) = self.client.send_offset_fetch_request(group, [req],
        #                  callback=get_or_init_offset_callback,
        #                  fail_on_error=False)
        #
        #    #Increment the offset with 1 so that message corresponding to last
        #    #committed offset doesn't get replayed
        #    if offset != 0:
        #       offset +=1
        #
        #    self.offsets[partition] = offset

        for partition in partitions:
            self.offsets[partition] = 0

    def __init__(self, client, group, topic, partitions=None, auto_commit=True,
                 auto_commit_every_n=AUTO_COMMIT_MSG_COUNT,
                 auto_commit_every_t=AUTO_COMMIT_INTERVAL):

        self.client = client
        self.topic = topic
        self.group = group
        self.client.load_metadata_for_topics(topic)
        self.offsets = {}

        if not partitions:
            partitions = self.client.topic_partitions[topic]

        # Variables for handling offset commits
        self.commit_lock = Lock()
        self.commit_timer = None
        self.count_since_commit = 0
        self.auto_commit = auto_commit
        self.auto_commit_every_n = auto_commit_every_n
        self.auto_commit_every_t = auto_commit_every_t

        # Set up the auto-commit timer
        if auto_commit is True and auto_commit_every_t is not None:
            self.commit_timer = ReentrantTimer(auto_commit_every_t,
                                               self.commit)
            self.commit_timer.start()

        def get_or_init_offset_callback(resp):
            if resp.error == ErrorMapping.NO_ERROR:
                return resp.offset
            elif resp.error == ErrorMapping.UNKNOWN_TOPIC_OR_PARTITON:
                return 0
            else:
                raise Exception("OffsetFetchRequest for topic=%s, "
                                "partition=%d failed with errorcode=%s" % (
                                    resp.topic, resp.partition, resp.error))

        # TODO add in check for testing which version kafka from the broker
        
        try:
            for partition in partitions:
                req = OffsetFetchRequest(topic, partition)
                (offset,) = self.client.send_offset_fetch_request(group, [req],
                              callback=get_or_init_offset_callback,
                              fail_on_error=False)
                self.offsets[partition] = offset
        except:
            for partition in partitions:
                self.offsets[partition] = 0

    def __init__(self, client, group, topic, partitions=None, auto_commit=True,
                 auto_commit_every_n=AUTO_COMMIT_MSG_COUNT,
                 auto_commit_every_t=AUTO_COMMIT_INTERVAL,
                 should_fetch_offset=False):

        self.client = client
        self.topic = topic
        self.group = group
        self.client.load_metadata_for_topics(topic)
        self.offsets = {}

        if not partitions:
            partitions = self.client.topic_partitions[topic]
        else:
            assert all(isinstance(x, numbers.Integral) for x in partitions)

        # Variables for handling offset commits
        self.commit_lock = Lock()
        self.commit_timer = None
        self.count_since_commit = 0
        self.auto_commit = auto_commit
        self.auto_commit_every_n = auto_commit_every_n
        self.auto_commit_every_t = auto_commit_every_t

        # Set up the auto-commit timer
        if auto_commit is True and auto_commit_every_t is not None:
            self.commit_timer = ReentrantTimer(auto_commit_every_t,
                                               self.commit)
            self.commit_timer.start()

        def get_or_init_offset_callback(resp):
            try:
                kafka.common.check_error(resp)
                return resp.offset
            except kafka.common.UnknownTopicOrPartitionError:
                return 0

        if auto_commit or should_fetch_offset:
            for partition in partitions:
                req = OffsetFetchRequest(topic, partition)
                (offset,) = self.client.send_offset_fetch_request(group, [req],
                              callback=get_or_init_offset_callback,
                              fail_on_error=False)
                self.offsets[partition] = offset
                log.info('For partition %d fetched offset %d.', partition, offset)
        else:
            for partition in partitions:
                self.offsets[partition] = 0
                log.info('Set the offset for partition %d to 0 due to not being able to fetch offsets.', partition)

    def __init__(self, client, group, topic, partitions=None, auto_commit=True,
                 auto_commit_every_n=AUTO_COMMIT_MSG_COUNT,
                 auto_commit_every_t=AUTO_COMMIT_INTERVAL,
                 offset_storage='zookeeper'):

        warnings.warn('deprecated -- this class will be removed in a future'
                      ' release. Use KafkaConsumer instead.',
                      DeprecationWarning)
        self.client = client
        self.topic = topic
        self.group = group
        self.client.load_metadata_for_topics(topic, ignore_leadernotavailable=True)
        self.offsets = {}

        if partitions is None:
            partitions = self.client.get_partition_ids_for_topic(topic)
        else:
            assert all(isinstance(x, numbers.Integral) for x in partitions)

        # Variables for handling offset commits
        self.commit_lock = Lock()
        self.commit_timer = None
        self.count_since_commit = 0
        self.auto_commit = auto_commit
        self.auto_commit_every_n = auto_commit_every_n
        self.auto_commit_every_t = auto_commit_every_t
        self.offset_storage = offset_storage

        # Set up the auto-commit timer
        if auto_commit is True and auto_commit_every_t is not None:
            self.commit_timer = ReentrantTimer(auto_commit_every_t,
                                               self.commit)
            self.commit_timer.start()

        # Set initial offsets
        if self.group is not None:
            self.fetch_last_known_offsets(partitions)
        else:
            for partition in partitions:
                self.offsets[partition] = 0

        # Register a cleanup handler
        def cleanup(obj):
            obj.stop()
        self._cleanup_func = cleanup
        atexit.register(cleanup, self)

        self.partition_info = False     # Do not return partition info in msgs

    def __init__(self, client, group, topic, partitions=None, auto_commit=True,
                 auto_commit_every_n=AUTO_COMMIT_MSG_COUNT,
                 auto_commit_every_t=AUTO_COMMIT_INTERVAL):

        self.client = client
        self.topic = topic
        self.group = group
        self.client.load_metadata_for_topics(topic)
        self.offsets = {}

        if not partitions:
            partitions = self.client.topic_partitions[topic]
        else:
            assert all(isinstance(x, numbers.Integral) for x in partitions)

        # Variables for handling offset commits
        self.commit_lock = Lock()
        self.commit_timer = None
        self.count_since_commit = 0
        self.auto_commit = auto_commit
        self.auto_commit_every_n = auto_commit_every_n
        self.auto_commit_every_t = auto_commit_every_t

        # add callback to be called when stopping consumer -
        # used in conjunction with ZSimpleConsumer to perform an action
        # prior to a repartition event.
        self.on_stop_callback = None

        # Set up the auto-commit timer
        if auto_commit is True and auto_commit_every_t is not None:
            self.commit_timer = ReentrantTimer(auto_commit_every_t,
                                               self.commit)
            self.commit_timer.start()

        def get_or_init_offset_callback(resp):
            try:
                kafka.common.check_error(resp)
                return resp.offset
            except kafka.common.UnknownTopicOrPartitionError:
                return 0

        for partition in partitions:
            req = OffsetFetchRequest(topic, partition)
            (offset,) = self.client.send_offset_fetch_request(group, [req],
                                                              callback=get_or_init_offset_callback,
                                                              fail_on_error=False)
            self.offsets[partition] = offset

    def __init__(self, client, group, topic, partitions=None, auto_commit=True,
                 auto_commit_every_n=AUTO_COMMIT_MSG_COUNT,
                 auto_commit_every_t=AUTO_COMMIT_INTERVAL,
                 offset_storage='zookeeper'):

        self.client = client
        self.topic = kafka_bytestring(topic)
        self.group = None if group is None else kafka_bytestring(group)
        self.client.load_metadata_for_topics(topic)
        self.offsets = {}

        if partitions is None:
            partitions = self.client.get_partition_ids_for_topic(topic)
        else:
            assert all(isinstance(x, numbers.Integral) for x in partitions)

        # Variables for handling offset commits
        self.commit_lock = Lock()
        self.commit_timer = None
        self.count_since_commit = 0
        self.auto_commit = auto_commit
        self.auto_commit_every_n = auto_commit_every_n
        self.auto_commit_every_t = auto_commit_every_t
        self.offset_storage = offset_storage

        # Set up the auto-commit timer
        if auto_commit is True and auto_commit_every_t is not None:
            self.commit_timer = ReentrantTimer(auto_commit_every_t,
                                               self.commit)
            self.commit_timer.start()

        # Set initial offsets
        if self.group is not None:
            self.fetch_last_known_offsets(partitions)
        else:
            for partition in partitions:
                self.offsets[partition] = 0

        # Register a cleanup handler
        def cleanup(obj):
            obj.stop()
        self._cleanup_func = cleanup
        atexit.register(cleanup, self)

        self.partition_info = False     # Do not return partition info in msgs

class Consumer(object):
    """
    Base class to be used by other consumers. Not to be used directly

    This base class provides logic for

    * initialization and fetching metadata of partitions
    * Auto-commit logic
    * APIs for fetching pending message count

    """
    def __init__(self, client, group, topic, partitions=None, auto_commit=True,
                 auto_commit_every_n=AUTO_COMMIT_MSG_COUNT,
                 auto_commit_every_t=AUTO_COMMIT_INTERVAL):

        self.client = client
        self.topic = kafka_bytestring(topic)
        self.group = None if group is None else kafka_bytestring(group)
        self.client.load_metadata_for_topics(topic)
        self.offsets = {}

        if partitions is None:
            partitions = self.client.get_partition_ids_for_topic(topic)
        else:
            assert all(isinstance(x, numbers.Integral) for x in partitions)

        # Variables for handling offset commits
        self.commit_lock = Lock()
        self.commit_timer = None
        self.count_since_commit = 0
        self.auto_commit = auto_commit
        self.auto_commit_every_n = auto_commit_every_n
        self.auto_commit_every_t = auto_commit_every_t

        # Set up the auto-commit timer
        if auto_commit is True and auto_commit_every_t is not None:
            self.commit_timer = ReentrantTimer(auto_commit_every_t,
                                               self.commit)
            self.commit_timer.start()

        # Set initial offsets
        if self.group is not None:
            self.fetch_last_known_offsets(partitions)
        else:
            for partition in partitions:
                self.offsets[partition] = 0

        # Register a cleanup handler
        def cleanup(obj):
            obj.stop()
        self._cleanup_func = cleanup
        atexit.register(cleanup, self)

        self.partition_info = False     # Do not return partition info in msgs

    def provide_partition_info(self):
        """
        Indicates that partition info must be returned by the consumer
        """
        self.partition_info = True

    def fetch_last_known_offsets(self, partitions=None):
        if self.group is None:
            raise ValueError('KafkaClient.group must not be None')

        if partitions is None:
            partitions = self.client.get_partition_ids_for_topic(self.topic)

        responses = self.client.send_offset_fetch_request(
            self.group,
            [OffsetFetchRequest(self.topic, p) for p in partitions],
            fail_on_error=False
        )

        for resp in responses:
            try:
                check_error(resp)
            # API spec says server wont set an error here
            # but 0.8.1.1 does actually...
            except UnknownTopicOrPartitionError:
                pass

            # -1 offset signals no commit is currently stored
            if resp.offset == -1:
                self.offsets[resp.partition] = 0

            # Otherwise we committed the stored offset
            # and need to fetch the next one
            else:
                self.offsets[resp.partition] = resp.offset

    def commit(self, partitions=None):
        """Commit stored offsets to Kafka via OffsetCommitRequest (v0)

        Keyword Arguments:
            partitions (list): list of partitions to commit, default is to commit
                all of them

        Returns: True on success, False on failure
        """
#.........这里部分代码省略.........

class Consumer(object):
    """
    Base class to be used by other consumers. Not to be used directly

    This base class provides logic for
    * initialization and fetching metadata of partitions
    * Auto-commit logic
    * APIs for fetching pending message count
    """
    def __init__(self, client, group, topic, partitions=None, auto_commit=True,
                 auto_commit_every_n=AUTO_COMMIT_MSG_COUNT,
                 auto_commit_every_t=AUTO_COMMIT_INTERVAL):

        self.client = client
        self.topic = topic
        self.group = group
        self.client.load_metadata_for_topics(topic)
        self.offsets = {}

        if not partitions:
            partitions = self.client.topic_partitions[topic]

        # Variables for handling offset commits
        self.commit_lock = Lock()
        self.commit_timer = None
        self.count_since_commit = 0
        self.auto_commit = auto_commit
        self.auto_commit_every_n = auto_commit_every_n
        self.auto_commit_every_t = auto_commit_every_t

        # Set up the auto-commit timer
        if auto_commit is True and auto_commit_every_t is not None:
            self.commit_timer = ReentrantTimer(auto_commit_every_t,
                                               self.commit)
            self.commit_timer.start()

        def get_or_init_offset_callback(resp):
            if resp.error == ErrorMapping.NO_ERROR:
                return resp.offset
            elif resp.error == ErrorMapping.UNKNOWN_TOPIC_OR_PARTITON:
                return 0
            else:
                raise Exception("OffsetFetchRequest for topic=%s, "
                                "partition=%d failed with errorcode=%s" % (
                                    resp.topic, resp.partition, resp.error))

        # TODO add in check for testing which version kafka from the broker
        
        try:
            for partition in partitions:
                req = OffsetFetchRequest(topic, partition)
                (offset,) = self.client.send_offset_fetch_request(group, [req],
                              callback=get_or_init_offset_callback,
                              fail_on_error=False)
                self.offsets[partition] = offset
        except:
            for partition in partitions:
                self.offsets[partition] = 0

    def commit(self, partitions=None):
        """
        Commit offsets for this consumer

        partitions: list of partitions to commit, default is to commit
                    all of them
        """

        # short circuit if nothing happened. This check is kept outside
        # to prevent un-necessarily acquiring a lock for checking the state
        if self.count_since_commit == 0:
            return

        with self.commit_lock:
            # Do this check again, just in case the state has changed
            # during the lock acquiring timeout
            if self.count_since_commit == 0:
                return

            reqs = []
            if not partitions:  # commit all partitions
                partitions = self.offsets.keys()

            for partition in partitions:
                offset = self.offsets[partition]
                log.debug("Commit offset %d in SimpleConsumer: "
                          "group=%s, topic=%s, partition=%s" %
                          (offset, self.group, self.topic, partition))

                reqs.append(OffsetCommitRequest(self.topic, partition,
                                                offset, None))

            resps = self.client.send_offset_commit_request(self.group, reqs)
            for resp in resps:
                assert resp.error == 0

            self.count_since_commit = 0

    def _auto_commit(self):
        """
        Check if we have to commit based on number of messages and commit
#.........这里部分代码省略.........

class Consumer(object):
    """
    Base class to be used by other consumers. Not to be used directly

    This base class provides logic for

    * initialization and fetching metadata of partitions
    * Auto-commit logic
    * APIs for fetching pending message count

    """
    def __init__(self, client, group, topic, partitions=None, auto_commit=True,
                 auto_commit_every_n=AUTO_COMMIT_MSG_COUNT,
                 auto_commit_every_t=AUTO_COMMIT_INTERVAL):

        self.client = client
        self.topic = topic
        self.group = group
        self.client.load_metadata_for_topics(topic)
        self.offsets = {}

        if not partitions:
            partitions = self.client.get_partition_ids_for_topic(topic)
        else:
            assert all(isinstance(x, numbers.Integral) for x in partitions)

        # Variables for handling offset commits
        self.commit_lock = Lock()
        self.commit_timer = None
        self.count_since_commit = 0
        self.auto_commit = auto_commit
        self.auto_commit_every_n = auto_commit_every_n
        self.auto_commit_every_t = auto_commit_every_t

        # Set up the auto-commit timer
        if auto_commit is True and auto_commit_every_t is not None:
            self.commit_timer = ReentrantTimer(auto_commit_every_t,
                                               self.commit)
            self.commit_timer.start()

        if auto_commit:
            self.fetch_last_known_offsets(partitions)
        else:
            for partition in partitions:
                self.offsets[partition] = 0

    def fetch_last_known_offsets(self, partitions=None):
        if not partitions:
            partitions = self.client.get_partition_ids_for_topic(self.topic)

        def get_or_init_offset(resp):
            try:
                kafka.common.check_error(resp)
                return resp.offset
            except UnknownTopicOrPartitionError:
                return 0

        for partition in partitions:
            req = OffsetFetchRequest(self.topic, partition)
            (resp,) = self.client.send_offset_fetch_request(self.group, [req],
                          fail_on_error=False)
            self.offsets[partition] = get_or_init_offset(resp)
        self.fetch_offsets = self.offsets.copy()

    def commit(self, partitions=None):
        """
        Commit offsets for this consumer

        Keyword Arguments:
            partitions (list): list of partitions to commit, default is to commit
                all of them
        """

        # short circuit if nothing happened. This check is kept outside
        # to prevent un-necessarily acquiring a lock for checking the state
        if self.count_since_commit == 0:
            return

        with self.commit_lock:
            # Do this check again, just in case the state has changed
            # during the lock acquiring timeout
            if self.count_since_commit == 0:
                return

            reqs = []
            if not partitions:  # commit all partitions
                partitions = self.offsets.keys()

            for partition in partitions:
                offset = self.offsets[partition]
                log.debug("Commit offset %d in SimpleConsumer: "
                          "group=%s, topic=%s, partition=%s" %
                          (offset, self.group, self.topic, partition))

                reqs.append(OffsetCommitRequest(self.topic, partition,
                                                offset, None))

            resps = self.client.send_offset_commit_request(self.group, reqs)
            for resp in resps:
                kafka.common.check_error(resp)
#.........这里部分代码省略.........

class SimpleConsumer(object):
    """
    A simple consumer implementation that consumes all partitions for a topic

    client: a connected KafkaClient
    group: a name for this consumer, used for offset storage and must be unique
    topic: the topic to consume

    auto_commit: default True. Whether or not to auto commit the offsets
    auto_commit_every_n: default 100. How many messages to consume
                         before a commit
    auto_commit_every_t: default 5000. How much time (in milliseconds) to
                         wait before commit

    Auto commit details:
    If both auto_commit_every_n and auto_commit_every_t are set, they will
    reset one another when one is triggered. These triggers simply call the
    commit method on this class. A manual call to commit will also reset
    these triggers

    """
    def __init__(self, client, group, topic, auto_commit=True,
                 auto_commit_every_n=AUTO_COMMIT_MSG_COUNT,
                 auto_commit_every_t=AUTO_COMMIT_INTERVAL):
        self.client = client
        self.topic = topic
        self.group = group
        self.client._load_metadata_for_topics(topic)
        self.offsets = {}

        # Variables for handling offset commits
        self.commit_lock = Lock()
        self.commit_timer = None
        self.count_since_commit = 0
        self.auto_commit = auto_commit
        self.auto_commit_every_n = auto_commit_every_n
        self.auto_commit_every_t = auto_commit_every_t

        # Set up the auto-commit timer
        if auto_commit is True and auto_commit_every_t is not None:
            self.commit_timer = ReentrantTimer(auto_commit_every_t,
                                               self._timed_commit)
            self.commit_timer.start()

        def get_or_init_offset_callback(resp):
            if resp.error == ErrorMapping.NO_ERROR:
                return resp.offset
            elif resp.error == ErrorMapping.UNKNOWN_TOPIC_OR_PARTITON:
                return 0
            else:
                raise Exception("OffsetFetchRequest for topic=%s, "
                                "partition=%d failed with errorcode=%s" % (
                                    resp.topic, resp.partition, resp.error))

        # Uncomment for 0.8.1
        #
        #for partition in self.client.topic_partitions[topic]:
        #    req = OffsetFetchRequest(topic, partition)
        #    (offset,) = self.client.send_offset_fetch_request(group, [req],
        #                  callback=get_or_init_offset_callback,
        #                  fail_on_error=False)
        #    self.offsets[partition] = offset

        for partition in self.client.topic_partitions[topic]:
            self.offsets[partition] = 0

    def stop(self):
        if self.commit_timer is not None:
            self.commit_timer.stop()
            self.commit()

    def seek(self, offset, whence):
        """
        Alter the current offset in the consumer, similar to fseek

        offset: how much to modify the offset
        whence: where to modify it from
                0 is relative to the earliest available offset (head)
                1 is relative to the current offset
                2 is relative to the latest known offset (tail)
        """
        if whence == 1:  # relative to current position
            for partition, _offset in self.offsets.items():
                self.offsets[partition] = _offset + offset
        elif whence in (0, 2):  # relative to beginning or end
            # divide the request offset by number of partitions,
            # distribute the remained evenly
            (delta, rem) = divmod(offset, len(self.offsets))
            deltas = {}
            for partition, r in izip_longest(self.offsets.keys(),
                                             repeat(1, rem), fillvalue=0):
                deltas[partition] = delta + r

            reqs = []
            for partition in self.offsets.keys():
                if whence == 0:
                    reqs.append(OffsetRequest(self.topic, partition, -2, 1))
                elif whence == 2:
                    reqs.append(OffsetRequest(self.topic, partition, -1, 1))
                else:
#.........这里部分代码省略.........

class Consumer(object):
    """
    Base class to be used by other consumers. Not to be used directly

    This base class provides logic for
    * initialization and fetching metadata of partitions
    * Auto-commit logic
    * APIs for fetching pending message count
    """
    def __init__(self, client, group, topic, partitions=None, auto_commit=True,
                 auto_commit_every_n=AUTO_COMMIT_MSG_COUNT,
                 auto_commit_every_t=AUTO_COMMIT_INTERVAL):

        self.client = client
        self.topic = topic
        self.group = group
        self.client.load_metadata_for_topics(topic)
        self.offsets = {}

        if not partitions:
            partitions = self.client.topic_partitions[topic]
        else:
            assert all(isinstance(x, numbers.Integral) for x in partitions)

        # Variables for handling offset commits
        self.commit_lock = Lock()
        self.commit_timer = None
        self.count_since_commit = 0
        self.auto_commit = auto_commit
        self.auto_commit_every_n = auto_commit_every_n
        self.auto_commit_every_t = auto_commit_every_t

        # add callback to be called when stopping consumer -
        # used in conjunction with ZSimpleConsumer to perform an action
        # prior to a repartition event.
        self.on_stop_callback = None

        # Set up the auto-commit timer
        if auto_commit is True and auto_commit_every_t is not None:
            self.commit_timer = ReentrantTimer(auto_commit_every_t,
                                               self.commit)
            self.commit_timer.start()

        def get_or_init_offset_callback(resp):
            try:
                kafka.common.check_error(resp)
                return resp.offset
            except kafka.common.UnknownTopicOrPartitionError:
                return 0

        for partition in partitions:
            req = OffsetFetchRequest(topic, partition)
            (offset,) = self.client.send_offset_fetch_request(group, [req],
                                                              callback=get_or_init_offset_callback,
                                                              fail_on_error=False)
            self.offsets[partition] = offset

    def commit(self, partitions=None):
        """
        Commit offsets for this consumer

        partitions: list of partitions to commit, default is to commit
                    all of them
        """

        # short circuit if nothing happened. This check is kept outside
        # to prevent un-necessarily acquiring a lock for checking the state
        if self.count_since_commit == 0:
            return

        with self.commit_lock:
            # Do this check again, just in case the state has changed
            # during the lock acquiring timeout
            if self.count_since_commit == 0:
                return

            reqs = []
            if not partitions:  # commit all partitions
                partitions = self.offsets.keys()

            for partition in partitions:
                offset = self.offsets[partition]
                log.info("Commit offset %d in SimpleConsumer: "
                         "group=%s, topic=%s, partition=%s" %
                         (offset, self.group, self.topic, partition))

                reqs.append(OffsetCommitRequest(self.topic, partition,
                                                offset, None))

            resps = self.client.send_offset_commit_request(self.group, reqs)
            for resp in resps:
                kafka.common.check_error(resp)

            self.count_since_commit = 0

    def commit_offsets(self, offsets):
        assert not self.auto_commit, 'cannot manually commit offsets if autocommit is True'
        with self.commit_lock:
            reqs = []
            for partition, offset in offsets.iteritems():
#.........这里部分代码省略.........

    def __init__(self, client, group, topic, partitions=None,
                 offset = ClientOffset.PREVIOUS_OR_CURRENT_BEGINNING,
                 auto_commit=True,
                 auto_commit_every_n=AUTO_COMMIT_MSG_COUNT,
                 auto_commit_every_t=AUTO_COMMIT_INTERVAL):

        self.client = client
        self.topic = topic
        self.group = group
        self.client.load_metadata_for_topics(topic)
        self.offsets = {}

        if not partitions:
            partitions = self.client.topic_partitions[topic]

        # Variables for handling offset commits
        self.commit_lock = Lock()
        self.commit_timer = None
        self.count_since_commit = 0
        self.auto_commit = auto_commit
        self.auto_commit_every_n = auto_commit_every_n
        self.auto_commit_every_t = auto_commit_every_t

        # Set up the auto-commit timer
        if auto_commit is True and auto_commit_every_t is not None:
            self.commit_timer = ReentrantTimer(auto_commit_every_t,
                                               self.commit)
            self.commit_timer.start()

        def get_current_offsets_callback(resp):
            if resp.error == ErrorMapping.NO_ERROR:
                return resp.offsets
            elif resp.error == ErrorMapping.UNKNOWN_TOPIC_OR_PARTITON:
                return 0
            else:
                raise BrokerResponseError("OffsetRequest for topic=%s, "
                                "partition=%d failed with errorcode=%s" % (
                                    resp.topic, resp.partition, resp.error))


        # callback for fetching on zookeeper
        def get_or_init_previous_offset_callback(resp):
            if resp.error == ErrorMapping.NO_ERROR:
                return resp.offset
            elif resp.error == ErrorMapping.UNKNOWN_TOPIC_OR_PARTITON:
                return 0
            else:
                raise BrokerResponseError("OffsetFetchRequest for topic=%s, "
                                "partition=%d failed with errorcode=%s" % (
                                    resp.topic, resp.partition, resp.error))

        currTimeMs = int(time.time()*1000)
        PAYLOAD_MAX_OFFSET = 2147483647
        for partition in partitions:
            # current stream
            req = OffsetRequest(topic, partition,currTimeMs,PAYLOAD_MAX_OFFSET)
            (raw_offsets,) = self.client.send_offset_request([req],
                          fail_on_error=False,
                          callback=get_current_offsets_callback)
            offset_start = raw_offsets[-1]
            offset_end   =   raw_offsets[0]

            # zookeeper
            req = OffsetFetchRequest(topic, partition)
            (last_offset,) = self.client.send_offset_fetch_request(group, [req],
                          callback=get_or_init_previous_offset_callback,
                          fail_on_error=False)

            if offset == ClientOffset.PREVIOUS_OR_CURRENT_BEGINNING:
                if offset_start <= last_offset <= offset_end:
                    self.offsets[partition] = last_offset
                else:
                    self.offsets[partition] = offset_start
            elif offset == ClientOffset.PREVIOUS:
                self.offsets[partition] = last_offset
            elif offset == ClientOffset.CURRENT_BEGINNING:
                self.offsets[partition] = offset_start
            elif offset == ClientOffset.LATEST:
                self.offsets[partition] = offset_end
            elif offset >=0:
                if offset_start <= offset <= offset_end:
                    for partition in partitions:
                        self.offsets[partition] = offset
                else:
                    raise ValueError("Invalid parameter value offset=%d,"
                                    "allowed range %d to %d"
                                    % (offset,offset_start,offset_end))

class Consumer(object):
    """
    Base class to be used by other consumers. Not to be used directly

    This base class provides logic for
    * initialization and fetching metadata of partitions
    * Auto-commit logic
    * APIs for fetching pending message count
    Offset:
        #ClientOffset.Zero or 0;
        ClientOffset.Previous or -1;
        ClientOffset.CurrentBeginning or -2;
        ClientOffset.PreviousOrCurrentBeginning or -3; Default.
        ClientOffset.Latest or -4;
        Other value >= 0;
    """
    def __init__(self, client, group, topic, partitions=None,
                 offset = ClientOffset.PREVIOUS_OR_CURRENT_BEGINNING,
                 auto_commit=True,
                 auto_commit_every_n=AUTO_COMMIT_MSG_COUNT,
                 auto_commit_every_t=AUTO_COMMIT_INTERVAL):

        self.client = client
        self.topic = topic
        self.group = group
        self.client.load_metadata_for_topics(topic)
        self.offsets = {}

        if not partitions:
            partitions = self.client.topic_partitions[topic]

        # Variables for handling offset commits
        self.commit_lock = Lock()
        self.commit_timer = None
        self.count_since_commit = 0
        self.auto_commit = auto_commit
        self.auto_commit_every_n = auto_commit_every_n
        self.auto_commit_every_t = auto_commit_every_t

        # Set up the auto-commit timer
        if auto_commit is True and auto_commit_every_t is not None:
            self.commit_timer = ReentrantTimer(auto_commit_every_t,
                                               self.commit)
            self.commit_timer.start()

        def get_current_offsets_callback(resp):
            if resp.error == ErrorMapping.NO_ERROR:
                return resp.offsets
            elif resp.error == ErrorMapping.UNKNOWN_TOPIC_OR_PARTITON:
                return 0
            else:
                raise BrokerResponseError("OffsetRequest for topic=%s, "
                                "partition=%d failed with errorcode=%s" % (
                                    resp.topic, resp.partition, resp.error))


        # callback for fetching on zookeeper
        def get_or_init_previous_offset_callback(resp):
            if resp.error == ErrorMapping.NO_ERROR:
                return resp.offset
            elif resp.error == ErrorMapping.UNKNOWN_TOPIC_OR_PARTITON:
                return 0
            else:
                raise BrokerResponseError("OffsetFetchRequest for topic=%s, "
                                "partition=%d failed with errorcode=%s" % (
                                    resp.topic, resp.partition, resp.error))

        currTimeMs = int(time.time()*1000)
        PAYLOAD_MAX_OFFSET = 2147483647
        for partition in partitions:
            # current stream
            req = OffsetRequest(topic, partition,currTimeMs,PAYLOAD_MAX_OFFSET)
            (raw_offsets,) = self.client.send_offset_request([req],
                          fail_on_error=False,
                          callback=get_current_offsets_callback)
            offset_start = raw_offsets[-1]
            offset_end   =   raw_offsets[0]

            # zookeeper
            req = OffsetFetchRequest(topic, partition)
            (last_offset,) = self.client.send_offset_fetch_request(group, [req],
                          callback=get_or_init_previous_offset_callback,
                          fail_on_error=False)

            if offset == ClientOffset.PREVIOUS_OR_CURRENT_BEGINNING:
                if offset_start <= last_offset <= offset_end:
                    self.offsets[partition] = last_offset
                else:
                    self.offsets[partition] = offset_start
            elif offset == ClientOffset.PREVIOUS:
                self.offsets[partition] = last_offset
            elif offset == ClientOffset.CURRENT_BEGINNING:
                self.offsets[partition] = offset_start
            elif offset == ClientOffset.LATEST:
                self.offsets[partition] = offset_end
            elif offset >=0:
                if offset_start <= offset <= offset_end:
                    for partition in partitions:
                        self.offsets[partition] = offset
                else:
#.........这里部分代码省略.........