def __init__(self, host="localhost", port=9090, timeout=1000, type='ng', reuse=True, debug=False):
""" Init the event server stuff (nodes and co).
Args:
host (Optional[str or list]): hostname or IP address, string or a list of hostname.
port (Optional[int]): port number on which to connect.
timeout (Optional[int]): Controls how long the socket will wait for a response.
type (Optional[str]): The flume agent generation.
reuse (bool): using a single TCP connection, otherwhise open/close connection for each operation.
debug (bool): True show debug messages, otherwhise is quiet.
"""
self.host = host
if isinstance(self.host, basestring):
self.host = [self.host]
self.port = port
self.timeout = timeout
self.type = type
self.reuse = reuse
self.debug = debug
# NOTE: parse the host URI.
for entity in self.host:
self.default_nodes = split_hosts(entity, self.port)
log_debug("nodes available {}".format(self.default_nodes), debug=self.debug)
if not self.default_nodes:
raise ConfigurationError("need to specify at least one host")
# NOTE: init stuff to manage the pool.
self.active_nodes = [node for node in self.default_nodes]
self.cycle_nodes = cycle(self.active_nodes)
self.open_connections = {}
def __enter__(self):
""" Connect to an active node.
"""
try:
if not self.active_nodes:
raise StopIteration
for node in self.cycle_nodes:
try:
if not self.active_nodes:
raise StopIteration
# NOTE: try to re-use a connection.
self.current_node = node
if self.reuse and self._is_connected(
node=self.current_node):
log_debug('re-using connection to {0}'.format(
self.current_node),
debug=self.debug)
return self.open_connections[
self.current_node]['client']
# NOTE: new connection.
self.client, self.transport = self._connect(
*self.current_node)
self._add_node(node=self.current_node,
client=self.client,
transport=self.transport)
log_debug('opened new connection to {0}'.format(
self.current_node),
debug=self.debug)
except ConnectionFailure as e:
self._remove_node(node=self.current_node)
except StopIteration:
raise ServerSelectionError("no server available")
def __enter__(self):
""" Connect to an active node.
"""
try:
if not self.active_nodes:
raise StopIteration
for node in self.cycle_nodes:
try:
if not self.active_nodes:
raise StopIteration
# NOTE: try to re-use a connection.
self.current_node = node
if self.reuse and self._is_connected(node=self.current_node):
log_debug('re-using connection to {}'.format(self.current_node), debug=self.debug)
return self.open_connections[self.current_node]['client']
# NOTE: new connection.
self.client, self.transport = self._connect(*self.current_node)
self._add_node(node=self.current_node, client=self.client, transport=self.transport)
log_debug('opened new connection to {}'.format(self.current_node), debug=self.debug)
except ConnectionFailure as e:
self._remove_node(node=self.current_node)
except StopIteration:
raise ServerSelectionError("no server available")
def _remove_node(self, node):
""" Remove a node from the active nodes pool.
Args:
host (str): Hostname/port combo.
"""
log_debug("remove {0} from the active nodes".format(node), debug=self.debug)
self.open_connections.pop(node, None)
if node in self.active_nodes:
self.active_nodes.remove(node)
def _add_node(self, node, client, transport):
""" Add a node to the active nodes pool.
Args:
host (str): Hostname/port combo.
"""
log_debug("add {0} to the active nodes".format(node), debug=self.debug)
self.open_connections[node] = {'client': client, 'transport': transport}
if node not in self.active_nodes:
self.active_nodes.append(node)
def reconnect(self):
""" Helper will attempt to reconnect on nodes.
"""
for node in self.default_nodes:
try:
if node not in self.active_nodes:
log_debug('reconnecting to {}'.format(node), debug=self.debug)
client, transport = self._connect(*node)
self._add_node(node=node, client=client, transport=transport)
except ConnectionFailure as e:
log_debug('failed to reconnect to {}'.format(node), debug=self.debug)
def _remove_node(self, node):
""" Remove a node from the active nodes pool.
Args:
host (str): Hostname/port combo.
"""
log_debug("remove {0} from the active nodes".format(node),
debug=self.debug)
self.open_connections.pop(node, None)
if node in self.active_nodes:
self.active_nodes.remove(node)
def _add_node(self, node, client, transport):
""" Add a node to the active nodes pool.
Args:
host (str): Hostname/port combo.
"""
self.first_cycle = False
log_debug("add {} to the active nodes".format(node), debug=self.debug)
self.open_connections[node] = {'client': client, 'transport': transport}
self.active_nodes.append(node)
self.cycle_nodes = cycle(self.active_nodes)
def _add_node(self, node, client, transport):
""" Add a node to the active nodes pool.
Args:
host (str): Hostname/port combo.
"""
log_debug("add {0} to the active nodes".format(node), debug=self.debug)
self.open_connections[node] = {
'client': client,
'transport': transport
}
if node not in self.active_nodes:
self.active_nodes.append(node)
def reconnect(self):
""" Helper will attempt to reconnect on nodes.
"""
for node in self.default_nodes:
try:
if node not in self.active_nodes:
log_debug('reconnecting to {0}'.format(node),
debug=self.debug)
client, transport = self._connect(*node)
self._add_node(node=node,
client=client,
transport=transport)
except ConnectionFailure as e:
log_debug('failed to reconnect to {0}'.format(node),
debug=self.debug)
def __init__(self,
host="localhost",
port=9090,
timeout=1000,
type='ng',
reuse=True,
debug=False):
""" Init the event server stuff (nodes and co).
Args:
host (Optional[str or list]): hostname or IP address, string or a list of hostname.
port (Optional[int]): port number on which to connect.
timeout (Optional[int]): Controls how long the socket will wait for a response.
type (Optional[str]): The flume agent generation.
reuse (bool): using a single TCP connection, otherwhise open/close connection for each operation.
debug (bool): True show debug messages, otherwhise is quiet.
"""
self.host = host
if isinstance(self.host, basestring):
self.host = [self.host]
self.port = port
self.timeout = timeout
self.type = type
self.reuse = reuse
self.debug = debug
# NOTE: parse the host URI.
for entity in self.host:
self.default_nodes = split_hosts(entity, self.port)
log_debug("nodes available {0}".format(self.default_nodes),
debug=self.debug)
if not self.default_nodes:
raise ConfigurationError("need to specify at least one host")
# NOTE: init stuff to manage the pool.
self.active_nodes = [node for node in self.default_nodes]
self.cycle_nodes = cycle(self.active_nodes)
self.open_connections = {}
