/usr/lib/python2.7/dist-packages/pika/heartbeat.py is in python-pika 0.10.0-1.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 | """Handle AMQP Heartbeats"""
import logging
from pika import frame
LOGGER = logging.getLogger(__name__)
class HeartbeatChecker(object):
"""Checks to make sure that our heartbeat is received at the expected
intervals.
"""
MAX_IDLE_COUNT = 2
_CONNECTION_FORCED = 320
_STALE_CONNECTION = "Too Many Missed Heartbeats, No reply in %i seconds"
def __init__(self, connection, interval, idle_count=MAX_IDLE_COUNT):
"""Create a heartbeat on connection sending a heartbeat frame every
interval seconds.
:param pika.connection.Connection: Connection object
:param int interval: Heartbeat check interval
:param int idle_count: Number of heartbeat intervals missed until the
connection is considered idle and disconnects
"""
self._connection = connection
self._interval = interval
self._max_idle_count = idle_count
# Initialize counters
self._bytes_received = 0
self._bytes_sent = 0
self._heartbeat_frames_received = 0
self._heartbeat_frames_sent = 0
self._idle_byte_intervals = 0
# The handle for the last timer
self._timer = None
# Setup the timer to fire in _interval seconds
self._setup_timer()
@property
def active(self):
"""Return True if the connection's heartbeat attribute is set to this
instance.
:rtype True
"""
return self._connection.heartbeat is self
@property
def bytes_received_on_connection(self):
"""Return the number of bytes received by the connection bytes object.
:rtype int
"""
return self._connection.bytes_received
@property
def connection_is_idle(self):
"""Returns true if the byte count hasn't changed in enough intervals
to trip the max idle threshold.
"""
return self._idle_byte_intervals >= self._max_idle_count
def received(self):
"""Called when a heartbeat is received"""
LOGGER.debug('Received heartbeat frame')
self._heartbeat_frames_received += 1
def send_and_check(self):
"""Invoked by a timer to send a heartbeat when we need to, check to see
if we've missed any heartbeats and disconnect our connection if it's
been idle too long.
"""
LOGGER.debug('Received %i heartbeat frames, sent %i',
self._heartbeat_frames_received,
self._heartbeat_frames_sent)
if self.connection_is_idle:
return self._close_connection()
# Connection has not received any data, increment the counter
if not self._has_received_data:
self._idle_byte_intervals += 1
else:
self._idle_byte_intervals = 0
# Update the counters of bytes sent/received and the frames received
self._update_counters()
# Send a heartbeat frame
self._send_heartbeat_frame()
# Update the timer to fire again
self._start_timer()
def stop(self):
"""Stop the heartbeat checker"""
if self._timer:
LOGGER.debug('Removing timeout for next heartbeat interval')
self._connection.remove_timeout(self._timer)
self._timer = None
def _close_connection(self):
"""Close the connection with the AMQP Connection-Forced value."""
LOGGER.info('Connection is idle, %i stale byte intervals',
self._idle_byte_intervals)
duration = self._max_idle_count * self._interval
text = HeartbeatChecker._STALE_CONNECTION % duration
self._connection.close(HeartbeatChecker._CONNECTION_FORCED, text)
self._connection._adapter_disconnect()
self._connection._on_disconnect(HeartbeatChecker._CONNECTION_FORCED,
text)
@property
def _has_received_data(self):
"""Returns True if the connection has received data on the connection.
:rtype: bool
"""
return not self._bytes_received == self.bytes_received_on_connection
def _new_heartbeat_frame(self):
"""Return a new heartbeat frame.
:rtype pika.frame.Heartbeat
"""
return frame.Heartbeat()
def _send_heartbeat_frame(self):
"""Send a heartbeat frame on the connection.
"""
LOGGER.debug('Sending heartbeat frame')
self._connection._send_frame(self._new_heartbeat_frame())
self._heartbeat_frames_sent += 1
def _setup_timer(self):
"""Use the connection objects delayed_call function which is
implemented by the Adapter for calling the check_heartbeats function
every interval seconds.
"""
self._timer = self._connection.add_timeout(self._interval,
self.send_and_check)
def _start_timer(self):
"""If the connection still has this object set for heartbeats, add a
new timer.
"""
if self.active:
self._setup_timer()
def _update_counters(self):
"""Update the internal counters for bytes sent and received and the
number of frames received
"""
self._bytes_sent = self._connection.bytes_sent
self._bytes_received = self._connection.bytes_received
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