ansible/library/utilities/wait_for

464 lines
17 KiB
Python

#!/usr/bin/python
# -*- coding: utf-8 -*-
# (c) 2012, Jeroen Hoekx <jeroen@hoekx.be>
#
# This file is part of Ansible
#
# Ansible is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Ansible is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Ansible. If not, see <http://www.gnu.org/licenses/>.
import socket
import datetime
import time
import sys
import re
import binascii
HAS_PSUTIL = False
try:
import psutil
HAS_PSUTIL = True
# just because we can import it on Linux doesn't mean we will use it
except ImportError:
pass
DOCUMENTATION = '''
---
module: wait_for
short_description: Waits for a condition before continuing.
description:
- Waiting for a port to become available is useful for when services
are not immediately available after their init scripts return -
which is true of certain Java application servers. It is also
useful when starting guests with the M(virt) module and
needing to pause until they are ready.
- This module can also be used to wait for a regex match a string to be present in a file.
- In 1.6 and later, this module can
also be used to wait for a file to be available or absent on the
filesystem.
- In X and later, this module can also be used to wait for active
connections to be closed before continuing, useful if a node
is being rotated out of a load balancer pool.
version_added: "0.7"
options:
host:
description:
- hostname or IP address to wait for
required: false
default: "127.0.0.1"
aliases: []
timeout:
description:
- maximum number of seconds to wait for
required: false
default: 300
delay:
description:
- number of seconds to wait before starting to poll
required: false
default: 0
port:
description:
- port number to poll
required: false
state:
description:
- either C(present), C(started), or C(stopped), C(absent), or C(drained)
- When checking a port C(started) will ensure the port is open, C(stopped) will check that it is closed, C(drained) will check for active connections
- When checking for a file or a search string C(present) or C(started) will ensure that the file or string is present before continuing, C(absent) will check that file is absent or removed
choices: [ "present", "started", "stopped", "absent", "drained" ]
default: "started"
path:
version_added: "1.4"
required: false
description:
- path to a file on the filesytem that must exist before continuing
search_regex:
version_added: "1.4"
required: false
description:
- Can be used to match a string in either a file or a socket connection. Defaults to a multiline regex.
exclude_hosts:
version_added: "1.x"
required: false
description:
- list of hosts or IPs to ignore when looking for active TCP connections for C(drained) state
notes:
- The ability to use search_regex with a port connection was added in 1.7.
requirements: []
author: Jeroen Hoekx, John Jarvis, Andrii Radyk
'''
EXAMPLES = '''
# wait 300 seconds for port 8000 to become open on the host, don't start checking for 10 seconds
- wait_for: port=8000 delay=10
# wait 300 seconds for port 8000 of any IP to close active connections, don't start checking for 10 seconds
- wait_for: host=0.0.0.0 port=8000 delay=10 state=drained
# wait 300 seconds for port 8000 of any IP to close active connections, ignoring connections for specified hosts
- wait_for: host=0.0.0.0 port=8000 state=drained exclude_hosts=10.2.1.2,10.2.1.3
# wait until the file /tmp/foo is present before continuing
- wait_for: path=/tmp/foo
# wait until the string "completed" is in the file /tmp/foo before continuing
- wait_for: path=/tmp/foo search_regex=completed
# wait until the lock file is removed
- wait_for: path=/var/lock/file.lock state=absent
# wait until the process is finished and pid was destroyed
- wait_for: path=/proc/3466/status state=absent
# Wait 300 seconds for port 22 to become open and contain "OpenSSH", don't start checking for 10 seconds
- local_action: wait_for port=22 host="{{ inventory_hostname }}" search_regex=OpenSSH delay=10
'''
class TCPConnectionInfo(object):
"""
This is a generic TCP Connection Info strategy class that relies
on the psutil module, which is not ideal for targets, but necessary
for cross platform support.
A subclass may wish to override some or all of these methods.
- _get_exclude_ips()
- get_active_connections()
All subclasses MUST define platform and distribution (which may be None).
"""
platform = 'Generic'
distribution = None
match_all_ips = {
socket.AF_INET: '0.0.0.0',
socket.AF_INET6: '::',
}
connection_states = {
'01': 'ESTABLISHED',
'02': 'SYN_SENT',
'03': 'SYN_RECV',
'04': 'FIN_WAIT1',
'05': 'FIN_WAIT2',
'06': 'TIME_WAIT',
}
def __new__(cls, *args, **kwargs):
return load_platform_subclass(TCPConnectionInfo, args, kwargs)
def __init__(self, module):
self.module = module
self.name = module.params['name']
(self.family, self.ip) = _convert_host_to_ip(self.module.params['host'])
self.port = int(self.module.params['port'])
self.exclude_ips = self._get_exclude_ips()
if not HAS_PSUTIL:
module.fail_json(msg="psutil module required for wait_for")
def _get_exclude_ips(self):
if self.module.params['exclude_hosts'] is None:
return []
exclude_hosts = self.module.params['exclude_hosts'].split(',')
return [ _convert_host_to_hex(h)[1] for h in exclude_hosts ]
def get_active_connections_count(self):
active_connections = 0
for p in psutil.process_iter():
connections = p.get_connections(kind='inet')
for conn in connections:
if conn.status not in self.connection_states.values():
continue
(local_ip, local_port) = conn.local_address
if self.port == local_port and self.ip in [self.match_all_ips[self.family], local_ip]:
(remote_ip, remote_port) = conn.remote_address
if remote_ip not in self.exclude_ips:
active_connections += 1
return active_connections
# ===========================================
# Subclass: Linux
class LinuxTCPConnectionInfo(TCPConnectionInfo):
"""
This is a TCP Connection Info evaluation strategy class
that utilizes information from Linux's procfs. While less universal,
does allow Linux targets to not require an additional library.
"""
platform = 'Linux'
distribution = None
source_file = {
socket.AF_INET: '/proc/net/tcp',
socket.AF_INET6: '/proc/net/tcp6'
}
match_all_ips = {
socket.AF_INET: '00000000',
socket.AF_INET6: '00000000000000000000000000000000',
}
local_address_field = 1
remote_address_field = 2
connection_state_field = 3
def __init__(self, module):
self.module = module
self.name = module.params['name']
(self.family, self.ip) = _convert_host_to_hex(module.params['host'])
self.port = "%0.4X" % int(module.params['port'])
self.exclude_ips = self._get_exclude_ips()
def _get_exclude_ips(self):
if self.module.params['exclude_hosts'] is None:
return []
exclude_hosts = self.module.params['exclude_hosts'].split(',')
return [ _convert_host_to_hex(h) for h in exclude_hosts ]
def get_active_connections_count(self):
active_connections = 0
f = open(self.source_file[self.family])
for tcp_connection in f.readlines():
tcp_connection = tcp_connection.strip().split(' ')
if tcp_connection[self.local_address_field] == 'local_address':
continue
if tcp_connection[self.connection_state_field] not in self.connection_states:
continue
(local_ip, local_port) = tcp_connection[self.local_address_field].split(':')
if self.port == local_port and self.ip in [self.match_all_ips[self.family], local_ip]:
(remote_ip, remote_port) = tcp_connection[self.remote_address_field].split(':')
if remote_ip not in self.exclude_ips:
active_connections += 1
f.close()
return active_connections
def _convert_host_to_ip(host):
"""
Perform forward DNS resolution on host, IP will give the same IP
Args:
host: String with either hostname, IPv4, or IPv6 address
Returns:
Tuple containing address family and IP
"""
addrinfo = socket.getaddrinfo(host, 80, 0, 0, socket.SOL_TCP)[0]
return (addrinfo[0], addrinfo[4][0])
def _convert_host_to_hex(host):
"""
Convert the provided host to the format in /proc/net/tcp*
/proc/net/tcp uses little-endian four byte hex for ipv4
/proc/net/tcp6 uses little-endian per 4B word for ipv6
Args:
host: String with either hostname, IPv4, or IPv6 address
Returns:
Tuple containing address family and the little-endian converted host
"""
(family, ip) = _convert_host_to_ip(host)
hexed = binascii.hexlify(socket.inet_pton(family, ip)).upper()
if family == socket.AF_INET:
hexed = _little_endian_convert_32bit(hexed)
elif family == socket.AF_INET6:
# xrange loops through each 8 character (4B) set in the 128bit total
hexed = "".join([ _little_endian_convert_32bit(hexed[x:x+8]) for x in xrange(0, 32, 8) ])
return (family, hexed)
def _little_endian_convert_32bit(block):
"""
Convert to little-endian, effectively transposing
the order of the four byte word
12345678 -> 78563412
Args:
block: String containing a 4 byte hex representation
Returns:
String containing the little-endian converted block
"""
# xrange starts at 6, and increments by -2 until it reaches -2
# which lets us start at the end of the string block and work to the begining
return "".join([ block[x:x+2] for x in xrange(6, -2, -2) ])
def main():
module = AnsibleModule(
argument_spec = dict(
host=dict(default='127.0.0.1'),
timeout=dict(default=300),
connect_timeout=dict(default=5),
delay=dict(default=0),
port=dict(default=None),
path=dict(default=None),
search_regex=dict(default=None),
state=dict(default='started', choices=['started', 'stopped', 'present', 'absent', 'drained']),
exclude_hosts=dict(default=None, type='list')
),
)
params = module.params
host = params['host']
timeout = int(params['timeout'])
connect_timeout = int(params['connect_timeout'])
delay = int(params['delay'])
if params['port']:
port = int(params['port'])
else:
port = None
state = params['state']
path = params['path']
search_regex = params['search_regex']
if params['exclude_hosts']:
exclude_hosts = params['exclude_hosts'].split(',')
else:
exclude_hosts = []
if port and path:
module.fail_json(msg="port and path parameter can not both be passed to wait_for")
if path and state == 'stopped':
module.fail_json(msg="state=stopped should only be used for checking a port in the wait_for module")
if path and state == 'drained':
module.fail_json(msg="state=drained should only be used for checking a port in the wait_for module")
if exclude_hosts and state != 'drained':
module.fail_json(msg="exclude_hosts should only be with state=drained")
start = datetime.datetime.now()
if delay:
time.sleep(delay)
if state in [ 'stopped', 'absent' ]:
### first wait for the stop condition
end = start + datetime.timedelta(seconds=timeout)
while datetime.datetime.now() < end:
if path:
try:
f = open(path)
f.close()
time.sleep(1)
pass
except IOError:
break
elif port:
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.settimeout(connect_timeout)
try:
s.connect( (host, port) )
s.shutdown(socket.SHUT_RDWR)
s.close()
time.sleep(1)
except:
break
else:
elapsed = datetime.datetime.now() - start
if port:
module.fail_json(msg="Timeout when waiting for %s:%s to stop." % (host, port), elapsed=elapsed.seconds)
elif path:
module.fail_json(msg="Timeout when waiting for %s to be absent." % (path), elapsed=elapsed.seconds)
elif state in ['started', 'present']:
### wait for start condition
end = start + datetime.timedelta(seconds=timeout)
while datetime.datetime.now() < end:
if path:
try:
os.stat(path)
if search_regex:
try:
f = open(path)
try:
if re.search(search_regex, f.read(), re.MULTILINE):
break
else:
time.sleep(1)
finally:
f.close()
except IOError:
time.sleep(1)
pass
else:
break
except OSError, e:
# File not present
if e.errno == 2:
time.sleep(1)
else:
elapsed = datetime.datetime.now() - start
module.fail_json(msg="Failed to stat %s, %s" % (path, e.strerror), elapsed=elapsed.seconds)
elif port:
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.settimeout(connect_timeout)
try:
s.connect( (host, port) )
if search_regex:
data = ''
matched = False
while 1:
data += s.recv(1024)
if not data:
break
elif re.search(search_regex, data, re.MULTILINE):
matched = True
break
if matched:
s.shutdown(socket.SHUT_RDWR)
s.close()
break
else:
s.shutdown(socket.SHUT_RDWR)
s.close()
break
except:
time.sleep(1)
pass
else:
elapsed = datetime.datetime.now() - start
if port:
if search_regex:
module.fail_json(msg="Timeout when waiting for search string %s in %s:%s" % (search_regex, host, port), elapsed=elapsed.seconds)
else:
module.fail_json(msg="Timeout when waiting for %s:%s" % (host, port), elapsed=elapsed.seconds)
elif path:
if search_regex:
module.fail_json(msg="Timeout when waiting for search string %s in %s" % (search_regex, path), elapsed=elapsed.seconds)
else:
module.fail_json(msg="Timeout when waiting for file %s" % (path), elapsed=elapsed.seconds)
elif state == 'drained':
### wait until all active connections are gone
end = start + datetime.timedelta(seconds=timeout)
tcpconns = TCPConnectionInfo(module)
while datetime.datetime.now() < end:
try:
if tcpconns.get_active_connections_count() == 0:
break
except IOError:
pass
time.sleep(1)
else:
elapsed = datetime.datetime.now() - start
module.fail_json(msg="Timeout when waiting for %s:%s to drain" % (host, port), elapsed=elapsed.seconds)
elapsed = datetime.datetime.now() - start
module.exit_json(state=state, port=port, search_regex=search_regex, path=path, elapsed=elapsed.seconds)
# import module snippets
from ansible.module_utils.basic import *
main()