PEP8-ify most of the files

consumer.py and conn.py will be done later after pending merges

1 files changed, 166 insertions, 65 deletions

diff --git a/kafka/protocol.py b/kafka/protocol.py
index 94a7f2a..6bd5c73 100644
--- a/kafka/protocol.py
+++ b/kafka/protocol.py
@@ -18,10 +18,12 @@ from kafka.util import (
 
 log = logging.getLogger("kafka")
 
+
 class KafkaProtocol(object):
     """
-    Class to encapsulate all of the protocol encoding/decoding. This class does not
-    have any state associated with it, it is purely for organization.
+    Class to encapsulate all of the protocol encoding/decoding.
+    This class does not have any state associated with it, it is purely
+    for organization.
     """
     PRODUCE_KEY       = 0
     FETCH_KEY         = 1
@@ -44,18 +46,18 @@ class KafkaProtocol(object):
         """
         Encode the common request envelope
         """
-        return struct.pack('>hhih%ds' % len(client_id), 
+        return struct.pack('>hhih%ds' % len(client_id),
                            request_key,          # ApiKey
                            0,                    # ApiVersion
                            correlation_id,       # CorrelationId
-                           len(client_id),       #
+                           len(client_id),
                            client_id)            # ClientId
 
     @classmethod
     def _encode_message_set(cls, messages):
         """
-        Encode a MessageSet. Unlike other arrays in the protocol, MessageSets are 
-        not length-prefixed
+        Encode a MessageSet. Unlike other arrays in the protocol,
+        MessageSets are not length-prefixed
 
         Format
         ======
@@ -66,7 +68,8 @@ class KafkaProtocol(object):
         message_set = ""
         for message in messages:
             encoded_message = KafkaProtocol._encode_message(message)
-            message_set += struct.pack('>qi%ds' % len(encoded_message), 0, len(encoded_message), encoded_message)
+            message_set += struct.pack('>qi%ds' % len(encoded_message), 0,
+                                       len(encoded_message), encoded_message)
         return message_set
 
     @classmethod
@@ -74,10 +77,10 @@ class KafkaProtocol(object):
         """
         Encode a single message.
 
-        The magic number of a message is a format version number. The only supported
-        magic number right now is zero
+        The magic number of a message is a format version number.
+        The only supported magic number right now is zero
 
-        Format 
+        Format
         ======
         Message => Crc MagicByte Attributes Key Value
           Crc => int32
@@ -96,24 +99,27 @@ class KafkaProtocol(object):
             raise Exception("Unexpected magic number: %d" % message.magic)
         return msg
 
-
     @classmethod
     def _decode_message_set_iter(cls, data):
         """
         Iteratively decode a MessageSet
 
-        Reads repeated elements of (offset, message), calling decode_message to decode a
-        single message. Since compressed messages contain futher MessageSets, these two methods
-        have been decoupled so that they may recurse easily.
+        Reads repeated elements of (offset, message), calling decode_message
+        to decode a single message. Since compressed messages contain futher
+        MessageSets, these two methods have been decoupled so that they may
+        recurse easily.
         """
         cur = 0
         while cur < len(data):
             try:
                 ((offset, ), cur) = relative_unpack('>q', data, cur)
                 (msg, cur) = read_int_string(data, cur)
-                for (offset, message) in KafkaProtocol._decode_message(msg, offset):
+                for (offset, message) in KafkaProtocol._decode_message(msg,
+                                                                       offset):
                     yield OffsetAndMessage(offset, message)
-            except BufferUnderflowError: # If we get a partial read of a message, stop
+
+            except BufferUnderflowError:
+                # If we get a partial read of a message, stop
                 raise StopIteration()
 
     @classmethod
@@ -121,9 +127,10 @@ class KafkaProtocol(object):
         """
         Decode a single Message
 
-        The only caller of this method is decode_message_set_iter. They are decoupled to 
-        support nested messages (compressed MessageSets). The offset is actually read from
-        decode_message_set_iter (it is part of the MessageSet payload).
+        The only caller of this method is decode_message_set_iter.
+        They are decoupled to support nested messages (compressed MessageSets).
+        The offset is actually read from decode_message_set_iter (it is part
+        of the MessageSet payload).
         """
         ((crc, magic, att), cur) = relative_unpack('>iBB', data, 0)
         if crc != zlib.crc32(data[4:]):
@@ -131,23 +138,29 @@ class KafkaProtocol(object):
 
         (key, cur) = read_int_string(data, cur)
         (value, cur) = read_int_string(data, cur)
-        if att & KafkaProtocol.ATTRIBUTE_CODEC_MASK == KafkaProtocol.CODEC_NONE:
+
+        codec = att & KafkaProtocol.ATTRIBUTE_CODEC_MASK
+
+        if codec == KafkaProtocol.CODEC_NONE:
             yield (offset, Message(magic, att, key, value))
-        elif att & KafkaProtocol.ATTRIBUTE_CODEC_MASK == KafkaProtocol.CODEC_GZIP:
+
+        elif codec == KafkaProtocol.CODEC_GZIP:
             gz = gzip_decode(value)
-            for (offset, message) in KafkaProtocol._decode_message_set_iter(gz):
-                yield (offset, message)
-        elif att & KafkaProtocol.ATTRIBUTE_CODEC_MASK == KafkaProtocol.CODEC_SNAPPY:
+            for (offset, msg) in KafkaProtocol._decode_message_set_iter(gz):
+                yield (offset, msg)
+
+        elif codec == KafkaProtocol.CODEC_SNAPPY:
             snp = snappy_decode(value)
-            for (offset, message) in KafkaProtocol._decode_message_set_iter(snp):
-                yield (offset, message)
+            for (offset, msg) in KafkaProtocol._decode_message_set_iter(snp):
+                yield (offset, msg)
 
     ##################
     #   Public API   #
     ##################
 
     @classmethod
-    def encode_produce_request(cls, client_id, correlation_id, payloads=[], acks=1, timeout=1000):
+    def encode_produce_request(cls, client_id, correlation_id,
+                               payloads=None, acks=1, timeout=1000):
         """
         Encode some ProduceRequest structs
 
@@ -161,39 +174,53 @@ class KafkaProtocol(object):
             1: written to disk by the leader
             2+: waits for this many number of replicas to sync
             -1: waits for all replicas to be in sync
-        timeout: Maximum time the server will wait for acks from replicas. This is _not_ a socket timeout
+        timeout: Maximum time the server will wait for acks from replicas.
+                 This is _not_ a socket timeout
         """
+        payloads = [] if payloads is None else payloads
         grouped_payloads = group_by_topic_and_partition(payloads)
-        message = cls._encode_message_header(client_id, correlation_id, KafkaProtocol.PRODUCE_KEY)
+
+        message = cls._encode_message_header(client_id, correlation_id,
+                                             KafkaProtocol.PRODUCE_KEY)
+
         message += struct.pack('>hii', acks, timeout, len(grouped_payloads))
+
         for topic, topic_payloads in grouped_payloads.items():
-            message += struct.pack('>h%dsi' % len(topic), len(topic), topic, len(topic_payloads))
+            message += struct.pack('>h%dsi' % len(topic),
+                                   len(topic), topic, len(topic_payloads))
+
             for partition, payload in topic_payloads.items():
-                message_set = KafkaProtocol._encode_message_set(payload.messages)
-                message += struct.pack('>ii%ds' % len(message_set), partition, len(message_set), message_set)
+                msg_set = KafkaProtocol._encode_message_set(payload.messages)
+                message += struct.pack('>ii%ds' % len(msg_set), partition,
+                                       len(msg_set), msg_set)
+
         return struct.pack('>i%ds' % len(message), len(message), message)
 
     @classmethod
     def decode_produce_response(cls, data):
         """
-        Decode bytes to a ProduceResponse 
+        Decode bytes to a ProduceResponse
 
         Params
         ======
         data: bytes to decode
         """
         ((correlation_id, num_topics), cur) = relative_unpack('>ii', data, 0)
+
         for i in range(num_topics):
             ((strlen,), cur) = relative_unpack('>h', data, cur)
-            topic = data[cur:cur+strlen]
+            topic = data[cur:cur + strlen]
             cur += strlen
             ((num_partitions,), cur) = relative_unpack('>i', data, cur)
             for i in range(num_partitions):
-                ((partition, error, offset), cur) = relative_unpack('>ihq', data, cur)
+                ((partition, error, offset), cur) = relative_unpack('>ihq',
+                                                                    data, cur)
+
                 yield ProduceResponse(topic, partition, error, offset)
 
     @classmethod
-    def encode_fetch_request(cls, client_id, correlation_id, payloads=[], max_wait_time=100, min_bytes=4096):
+    def encode_fetch_request(cls, client_id, correlation_id, payloads=None,
+                             max_wait_time=100, min_bytes=4096):
         """
         Encodes some FetchRequest structs
 
@@ -203,17 +230,27 @@ class KafkaProtocol(object):
         correlation_id: string
         payloads: list of FetchRequest
         max_wait_time: int, how long to block waiting on min_bytes of data
-        min_bytes: int, the minimum number of bytes to accumulate before returning the response
+        min_bytes: int, the minimum number of bytes to accumulate before
+                   returning the response
         """
-        
+
+        payloads = [] if payloads is None else payloads
         grouped_payloads = group_by_topic_and_partition(payloads)
-        message = cls._encode_message_header(client_id, correlation_id, KafkaProtocol.FETCH_KEY)
-        message += struct.pack('>iiii', -1, max_wait_time, min_bytes, len(grouped_payloads)) # -1 is the replica id
+
+        message = cls._encode_message_header(client_id, correlation_id,
+                                             KafkaProtocol.FETCH_KEY)
+
+        # -1 is the replica id
+        message += struct.pack('>iiii', -1, max_wait_time, min_bytes,
+                               len(grouped_payloads))
+
         for topic, topic_payloads in grouped_payloads.items():
             message += write_short_string(topic)
             message += struct.pack('>i', len(topic_payloads))
             for partition, payload in topic_payloads.items():
-                message += struct.pack('>iqi', partition, payload.offset, payload.max_bytes)
+                message += struct.pack('>iqi', partition, payload.offset,
+                                       payload.max_bytes)
+
         return struct.pack('>i%ds' % len(message), len(message), message)
 
     @classmethod
@@ -226,25 +263,41 @@ class KafkaProtocol(object):
         data: bytes to decode
         """
         ((correlation_id, num_topics), cur) = relative_unpack('>ii', data, 0)
+
         for i in range(num_topics):
             (topic, cur) = read_short_string(data, cur)
             ((num_partitions,), cur) = relative_unpack('>i', data, cur)
+
             for i in range(num_partitions):
-                ((partition, error, highwater_mark_offset), cur) = relative_unpack('>ihq', data, cur)
+                ((partition, error, highwater_mark_offset), cur) = \
+                                        relative_unpack('>ihq', data, cur)
+
                 (message_set, cur) = read_int_string(data, cur)
-                yield FetchResponse(topic, partition, error, highwater_mark_offset,
+
+                yield FetchResponse(
+                        topic, partition, error,
+                        highwater_mark_offset,
                         KafkaProtocol._decode_message_set_iter(message_set))
 
     @classmethod
-    def encode_offset_request(cls, client_id, correlation_id, payloads=[]):
+    def encode_offset_request(cls, client_id, correlation_id, payloads=None):
+        payloads = [] if payloads is None else payloads
         grouped_payloads = group_by_topic_and_partition(payloads)
-        message = cls._encode_message_header(client_id, correlation_id, KafkaProtocol.OFFSET_KEY)
-        message += struct.pack('>ii', -1, len(grouped_payloads)) # -1 is the replica id
+
+        message = cls._encode_message_header(client_id, correlation_id,
+                                             KafkaProtocol.OFFSET_KEY)
+
+        # -1 is the replica id
+        message += struct.pack('>ii', -1, len(grouped_payloads))
+
         for topic, topic_payloads in grouped_payloads.items():
             message += write_short_string(topic)
             message += struct.pack('>i', len(topic_payloads))
+
             for partition, payload in topic_payloads.items():
-                message += struct.pack('>iqi', partition, payload.time, payload.max_offsets)
+                message += struct.pack('>iqi', partition, payload.time,
+                                       payload.max_offsets)
+
         return struct.pack('>i%ds' % len(message), len(message), message)
 
     @classmethod
@@ -257,19 +310,24 @@ class KafkaProtocol(object):
         data: bytes to decode
         """
         ((correlation_id, num_topics), cur) = relative_unpack('>ii', data, 0)
+
         for i in range(num_topics):
             (topic, cur) = read_short_string(data, cur)
             ((num_partitions,), cur) = relative_unpack('>i', data, cur)
+
             for i in range(num_partitions):
-                ((partition, error, num_offsets,), cur) = relative_unpack('>ihi', data, cur)
+                ((partition, error, num_offsets,), cur) = \
+                                         relative_unpack('>ihi', data, cur)
+
                 offsets = []
                 for j in range(num_offsets):
                     ((offset,), cur) = relative_unpack('>q', data, cur)
                     offsets.append(offset)
+
                 yield OffsetResponse(topic, partition, error, tuple(offsets))
 
     @classmethod
-    def encode_metadata_request(cls, client_id, correlation_id, topics=[]):
+    def encode_metadata_request(cls, client_id, correlation_id, topics=None):
         """
         Encode a MetadataRequest
 
@@ -279,10 +337,15 @@ class KafkaProtocol(object):
         correlation_id: string
         topics: list of strings
         """
-        message = cls._encode_message_header(client_id, correlation_id, KafkaProtocol.METADATA_KEY)
+        topics = [] if topics is None else topics
+        message = cls._encode_message_header(client_id, correlation_id,
+                                             KafkaProtocol.METADATA_KEY)
+
         message += struct.pack('>i', len(topics))
+
         for topic in topics:
             message += struct.pack('>h%ds' % len(topic), len(topic), topic)
+
         return write_int_string(message)
 
     @classmethod
@@ -307,22 +370,34 @@ class KafkaProtocol(object):
         # Topic info
         ((num_topics,), cur) = relative_unpack('>i', data, cur)
         topicMetadata = {}
+
         for i in range(num_topics):
             ((topicError,), cur) = relative_unpack('>h', data, cur)
             (topicName, cur) = read_short_string(data, cur)
             ((num_partitions,), cur) = relative_unpack('>i', data, cur)
             partitionMetadata = {}
+
             for j in range(num_partitions):
-                ((partitionErrorCode, partition, leader, numReplicas), cur) = relative_unpack('>hiii', data, cur)
-                (replicas, cur) = relative_unpack('>%di' % numReplicas, data, cur)
+                ((partitionErrorCode, partition, leader, numReplicas), cur) = \
+                                           relative_unpack('>hiii', data, cur)
+
+                (replicas, cur) = relative_unpack('>%di' % numReplicas,
+                                                  data, cur)
+
                 ((numIsr,), cur) = relative_unpack('>i', data, cur)
                 (isr, cur) = relative_unpack('>%di' % numIsr, data, cur)
-                partitionMetadata[partition] = PartitionMetadata(topicName, partition, leader, replicas, isr)
+
+                partitionMetadata[partition] = \
+                        PartitionMetadata(topicName, partition, leader,
+                                          replicas, isr)
+
             topicMetadata[topicName] = partitionMetadata
+
         return (brokers, topicMetadata)
 
     @classmethod
-    def encode_offset_commit_request(cls, client_id, correlation_id, group, payloads):
+    def encode_offset_commit_request(cls, client_id, correlation_id,
+                                     group, payloads):
         """
         Encode some OffsetCommitRequest structs
 
@@ -333,16 +408,21 @@ class KafkaProtocol(object):
         group: string, the consumer group you are committing offsets for
         payloads: list of OffsetCommitRequest
         """
-        grouped_payloads= group_by_topic_and_partition(payloads)
-        message = cls._encode_message_header(client_id, correlation_id, KafkaProtocol.OFFSET_COMMIT_KEY)
+        grouped_payloads = group_by_topic_and_partition(payloads)
+
+        message = cls._encode_message_header(client_id, correlation_id,
+                                             KafkaProtocol.OFFSET_COMMIT_KEY)
         message += write_short_string(group)
         message += struct.pack('>i', len(grouped_payloads))
+
         for topic, topic_payloads in grouped_payloads.items():
             message += write_short_string(topic)
             message += struct.pack('>i', len(topic_payloads))
+
             for partition, payload in topic_payloads.items():
                 message += struct.pack('>iq', partition, payload.offset)
                 message += write_short_string(payload.metadata)
+
         return struct.pack('>i%ds' % len(message), len(message), message)
 
     @classmethod
@@ -357,15 +437,18 @@ class KafkaProtocol(object):
         ((correlation_id,), cur) = relative_unpack('>i', data, 0)
         (client_id, cur) = read_short_string(data, cur)
         ((num_topics,), cur) = relative_unpack('>i', data, cur)
+
         for i in xrange(num_topics):
             (topic, cur) = read_short_string(data, cur)
             ((num_partitions,), cur) = relative_unpack('>i', data, cur)
+
             for i in xrange(num_partitions):
                 ((partition, error), cur) = relative_unpack('>ih', data, cur)
                 yield OffsetCommitResponse(topic, partition, error)
 
     @classmethod
-    def encode_offset_fetch_request(cls, client_id, correlation_id, group, payloads):
+    def encode_offset_fetch_request(cls, client_id, correlation_id,
+                                    group, payloads):
         """
         Encode some OffsetFetchRequest structs
 
@@ -377,14 +460,19 @@ class KafkaProtocol(object):
         payloads: list of OffsetFetchRequest
         """
         grouped_payloads = group_by_topic_and_partition(payloads)
-        message = cls._encode_message_header(client_id, correlation_id, KafkaProtocol.OFFSET_FETCH_KEY)
+        message = cls._encode_message_header(client_id, correlation_id,
+                                             KafkaProtocol.OFFSET_FETCH_KEY)
+
         message += write_short_string(group)
         message += struct.pack('>i', len(grouped_payloads))
+
         for topic, topic_payloads in grouped_payloads.items():
             message += write_short_string(topic)
             message += struct.pack('>i', len(topic_payloads))
+
             for partition, payload in topic_payloads.items():
                 message += struct.pack('>i', partition)
+
         return struct.pack('>i%ds' % len(message), len(message), message)
 
     @classmethod
@@ -400,14 +488,19 @@ class KafkaProtocol(object):
         ((correlation_id,), cur) = relative_unpack('>i', data, 0)
         (client_id, cur) = read_short_string(data, cur)
         ((num_topics,), cur) = relative_unpack('>i', data, cur)
+
         for i in range(num_topics):
             (topic, cur) = read_short_string(data, cur)
             ((num_partitions,), cur) = relative_unpack('>i', data, cur)
+
             for i in range(num_partitions):
                 ((partition, offset), cur) = relative_unpack('>iq', data, cur)
                 (metadata, cur) = read_short_string(data, cur)
                 ((error,), cur) = relative_unpack('>h', data, cur)
-                yield OffsetFetchResponse(topic, partition, offset, metadata, error)
+
+                yield OffsetFetchResponse(topic, partition, offset,
+                                          metadata, error)
+
 
 def create_message(payload, key=None):
     """
@@ -420,6 +513,7 @@ def create_message(payload, key=None):
     """
     return Message(0, 0, key, payload)
 
+
 def create_gzip_message(payloads, key=None):
     """
     Construct a Gzipped Message containing multiple Messages
@@ -433,9 +527,13 @@ def create_gzip_message(payloads, key=None):
     key: bytes, a key used for partition routing (optional)
     """
     message_set = KafkaProtocol._encode_message_set(
-            [create_message(payload) for payload in payloads])
-    gzipped = gzip_encode(message_set) 
-    return Message(0, 0x00 | (KafkaProtocol.ATTRIBUTE_CODEC_MASK & KafkaProtocol.CODEC_GZIP), key, gzipped)
+                        [create_message(payload) for payload in payloads])
+
+    gzipped = gzip_encode(message_set)
+    codec = KafkaProtocol.ATTRIBUTE_CODEC_MASK & KafkaProtocol.CODEC_GZIP
+
+    return Message(0, 0x00 | codec, key, gzipped)
+
 
 def create_snappy_message(payloads, key=None):
     """
@@ -450,6 +548,9 @@ def create_snappy_message(payloads, key=None):
     key: bytes, a key used for partition routing (optional)
     """
     message_set = KafkaProtocol._encode_message_set(
-            [create_message(payload) for payload in payloads])
-    snapped = snappy_encode(message_set) 
-    return Message(0, 0x00 | (KafkaProtocol.ATTRIBUTE_CODEC_MASK & KafkaProtocol.CODEC_SNAPPY), key, snapped)
+                            [create_message(payload) for payload in payloads])
+
+    snapped = snappy_encode(message_set)
+    codec = KafkaProtocol.ATTRIBUTE_CODEC_MASK & KafkaProtocol.CODEC_SNAPPY
+
+    return Message(0, 0x00 | codec, key, snapped)