Merge branch '0.9'

Conflicts:
	kafka/codec.py
	kafka/version.py
	test/test_producer.py
	test/test_producer_integration.py

1 files changed, 189 insertions, 0 deletions

diff --git a/kafka/cluster.py b/kafka/cluster.py
new file mode 100644
index 0000000..84ad1d3
--- /dev/null
+++ b/kafka/cluster.py
@@ -0,0 +1,189 @@
+from __future__ import absolute_import
+
+import copy
+import logging
+import random
+import time
+
+import kafka.common as Errors
+from kafka.common import BrokerMetadata
+from .future import Future
+
+log = logging.getLogger(__name__)
+
+
+class ClusterMetadata(object):
+    DEFAULT_CONFIG = {
+        'retry_backoff_ms': 100,
+        'metadata_max_age_ms': 300000,
+    }
+
+    def __init__(self, **configs):
+        self._brokers = {}
+        self._partitions = {}
+        self._groups = {}
+        self._version = 0
+        self._last_refresh_ms = 0
+        self._last_successful_refresh_ms = 0
+        self._need_update = False
+        self._future = None
+        self._listeners = set()
+
+        self.config = copy.copy(self.DEFAULT_CONFIG)
+        for key in self.config:
+            if key in configs:
+                self.config[key] = configs[key]
+
+    def brokers(self):
+        return set(self._brokers.values())
+
+    def broker_metadata(self, broker_id):
+        return self._brokers.get(broker_id)
+
+    def partitions_for_topic(self, topic):
+        if topic not in self._partitions:
+            return None
+        return set(self._partitions[topic].keys())
+
+    def leader_for_partition(self, partition):
+        if partition.topic not in self._partitions:
+            return None
+        return self._partitions[partition.topic].get(partition.partition)
+
+    def coordinator_for_group(self, group):
+        return self._groups.get(group)
+
+    def ttl(self):
+        """Milliseconds until metadata should be refreshed"""
+        now = time.time() * 1000
+        if self._need_update:
+            ttl = 0
+        else:
+            ttl = self._last_successful_refresh_ms + self.config['metadata_max_age_ms'] - now
+        retry = self._last_refresh_ms + self.config['retry_backoff_ms'] - now
+        return max(ttl, retry, 0)
+
+    def request_update(self):
+        """
+        Flags metadata for update, return Future()
+
+        Actual update must be handled separately. This method will only
+        change the reported ttl()
+        """
+        self._need_update = True
+        if not self._future or self._future.is_done:
+          self._future = Future()
+        return self._future
+
+    def topics(self):
+        return set(self._partitions.keys())
+
+    def failed_update(self, exception):
+        if self._future:
+            self._future.failure(exception)
+            self._future = None
+        self._last_refresh_ms = time.time() * 1000
+
+    def update_metadata(self, metadata):
+        # In the common case where we ask for a single topic and get back an
+        # error, we should fail the future
+        if len(metadata.topics) == 1 and metadata.topics[0][0] != 0:
+            error_code, topic, _ = metadata.topics[0]
+            error = Errors.for_code(error_code)(topic)
+            return self.failed_update(error)
+
+        if not metadata.brokers:
+            log.warning("No broker metadata found in MetadataResponse")
+
+        for node_id, host, port in metadata.brokers:
+            self._brokers.update({
+                node_id: BrokerMetadata(node_id, host, port)
+            })
+
+        # Drop any UnknownTopic, InvalidTopic, and TopicAuthorizationFailed
+        # but retain LeaderNotAvailable because it means topic is initializing
+        self._partitions = {}
+
+        for error_code, topic, partitions in metadata.topics:
+            error_type = Errors.for_code(error_code)
+            if error_type is Errors.NoError:
+                self._partitions[topic] = {}
+                for _, partition, leader, _, _ in partitions:
+                    self._partitions[topic][partition] = leader
+            elif error_type is Errors.LeaderNotAvailableError:
+                log.error("Topic %s is not available during auto-create"
+                          " initialization", topic)
+            elif error_type is Errors.UnknownTopicOrPartitionError:
+                log.error("Topic %s not found in cluster metadata", topic)
+            elif error_type is Errors.TopicAuthorizationFailedError:
+                log.error("Topic %s is not authorized for this client", topic)
+            elif error_type is Errors.InvalidTopicError:
+                log.error("'%s' is not a valid topic name", topic)
+            else:
+                log.error("Error fetching metadata for topic %s: %s",
+                          topic, error_type)
+
+        if self._future:
+            self._future.success(self)
+        self._future = None
+        self._need_update = False
+        self._version += 1
+        now = time.time() * 1000
+        self._last_refresh_ms = now
+        self._last_successful_refresh_ms = now
+        log.debug("Updated cluster metadata version %d to %s",
+                  self._version, self)
+
+        for listener in self._listeners:
+            listener(self)
+
+    def add_listener(self, listener):
+        """Add a callback function to be called on each metadata update"""
+        self._listeners.add(listener)
+
+    def remove_listener(self, listener):
+        """Remove a previously added listener callback"""
+        self._listeners.remove(listener)
+
+    def add_group_coordinator(self, group, response):
+        """Update with metadata for a group coordinator
+
+        group: name of group from GroupCoordinatorRequest
+        response: GroupCoordinatorResponse
+
+        returns True if metadata is updated, False on error
+        """
+        log.debug("Updating coordinator for %s: %s", group, response)
+        error_type = Errors.for_code(response.error_code)
+        if error_type is not Errors.NoError:
+            log.error("GroupCoordinatorResponse error: %s", error_type)
+            self._groups[group] = -1
+            return False
+
+        node_id = response.coordinator_id
+        coordinator = BrokerMetadata(
+            response.coordinator_id,
+            response.host,
+            response.port)
+
+        # Assume that group coordinators are just brokers
+        # (this is true now, but could diverge in future)
+        if node_id not in self._brokers:
+            self._brokers[node_id] = coordinator
+
+        # If this happens, either brokers have moved without
+        # changing IDs, or our assumption above is wrong
+        elif coordinator != self._brokers[node_id]:
+            log.error("GroupCoordinator metadata conflicts with existing"
+                      " broker metadata. Coordinator: %s, Broker: %s",
+                      coordinator, self._brokers[node_id])
+            self._groups[group] = node_id
+            return False
+
+        log.info("Group coordinator for %s is %s", group, coordinator)
+        self._groups[group] = node_id
+        return True
+
+    def __str__(self):
+        return 'Cluster(brokers: %d, topics: %d, groups: %d)' % \
+               (len(self._brokers), len(self._partitions), len(self._groups))