def __init__(self, socket_dir=None,
socket_file=None,
retry=2,
retry_interval=2):
self._hap_processes = []
socket_files = []
if socket_dir:
if not os.path.exists(socket_dir):
raise ValueError("socket directory does not exist "
"{}".format(socket_dir))
for _file in glob.glob(os.path.join(socket_dir, '*')):
if is_unix_socket(_file) and connected_socket(_file):
socket_files.append(_file)
elif (socket_file and is_unix_socket(socket_file) and
connected_socket(socket_file)):
socket_files.append(os.path.realpath(socket_file))
else:
raise ValueError("UNIX socket file was not set")
if not socket_files:
raise ValueError("No valid UNIX socket file was found, directory: "
"{} file: {}".format(socket_dir, socket_file))
for so_file in socket_files:
self._hap_processes.append(
_HAProxyProcess(so_file, retry, retry_interval)
)
def __init__(self,
socket_dir=None,
socket_file=None,
retry=2,
retry_interval=2):
self._hap_processes = []
socket_files = []
if socket_dir:
if not os.path.exists(socket_dir):
raise ValueError("socket directory does not exist "
"{}".format(socket_dir))
for _file in glob.glob(os.path.join(socket_dir, '*')):
if is_unix_socket(_file) and connected_socket(_file):
socket_files.append(_file)
elif (socket_file and is_unix_socket(socket_file)
and connected_socket(socket_file)):
socket_files.append(os.path.realpath(socket_file))
else:
raise ValueError("UNIX socket file was not set")
if not socket_files:
raise ValueError("No valid UNIX socket file was found, directory: "
"{} file: {}".format(socket_dir, socket_file))
for so_file in socket_files:
self._hap_processes.append(
_HAProxyProcess(so_file, retry, retry_interval))
def command(self, command, full_output=False):
"""Send a command to HAProxy over UNIX stats socket.
Newline character returned from haproxy is stripped off.
:param command: A valid command to execute
:type command: string
:param full_output: (optional) Return all output, by default
returns only the 1st line of the output
:type full_output: ``bool``
:return: 1st line of the output or the whole output as a list
:rtype: ``string`` or ``list`` if full_output is True
"""
data = [] # hold data returned from socket
raised = None # hold possible exception raised during connect phase
attempt = 0 # times to attempt to connect after a connection failure
if self.retry == 0:
# 0 means retry indefinitely
attempt = -1
elif self.retry is None:
# None means don't retry
attempt = 1
else:
# any other value means retry N times
attempt = self.retry + 1
while attempt != 0:
try:
unix_socket = None
tcpsocket = None
if is_unix_socket(self.sock):
unix_socket = socket.socket(socket.AF_UNIX,
socket.SOCK_STREAM)
unix_socket.settimeout(0.5)
unix_socket.connect(self.sock)
unix_socket.send(six.b(command + '\n'))
file_handle = unix_socket.makefile()
data = file_handle.read().splitlines()
else:
tcpsocket = socket.socket(socket.AF_INET,
socket.SOCK_STREAM)
parts = urisplit(self.sock)
if type(parts.gethost()
) == ipaddress.IPv4Address or hostname_resolves(
parts.gethost()):
tcpsocket.settimeout(2.0)
tcpsocket.connect((parts.gethost(), parts.getport()))
tcpsocket.send(six.b(command + '\n'))
file_handle = tcpsocket.makefile()
data = file_handle.read().splitlines()
else:
raise ValueError(
"URI is neither a valid IPAddess nor a resolvable hostname"
)
# I haven't seen a case where a running process which holds a
# UNIX socket will take more than few nanoseconds to accept a
# connection. But, I have seen cases where it takes ~0.5secs
# to get a respone from the socket. Thus I hard-code a timeout
# of 0.5ms
# TODO: consider having a configuration file for it
except socket.timeout:
raised = SocketTimeout(sock=self.sock)
except OSError as exc:
# while stress testing HAProxy and querying for all frontend
# metrics I sometimes get:
# OSError: [Errno 106] Transport endpoint is already connected
# catch this one only and reraise it withour exception
if exc.errno == errno.EISCONN:
raised = SocketTransportError(sock=self.sock)
elif exc.errno == errno.ECONNREFUSED:
raised = SocketConnectionError(self.sock)
else:
# for the rest of OSError exceptions just reraise them
raised = exc
else:
# HAProxy always send an empty string at the end
# we remove it as it adds noise for things like ACL/MAP and etc
# We only do that when we get more than 1 line, which only
# happens when we ask for ACL/MAP/etc and not for giving cmds
# such as disable/enable server
if len(data) > 1 and data[-1] == '':
data.pop()
# make sure possible previous errors are cleared
raised = None
# get out from the retry loop
break
finally:
if unix_socket:
unix_socket.close()
elif tcpsocket:
tcpsocket.close()
if raised:
time.sleep(self.retry_interval)
attempt -= 1
if raised:
raise raised
elif data:
if full_output:
return data
else:
return data[0]
else:
raise ValueError("no data returned from socket {}".format(
self.socket_file))