ansible/lib/ansible/module_utils/service.py
2015-11-03 09:53:18 -08:00

221 lines
7.9 KiB
Python

# This code is part of Ansible, but is an independent component.
# This particular file snippet, and this file snippet only, is BSD licensed.
# Modules you write using this snippet, which is embedded dynamically by Ansible
# still belong to the author of the module, and may assign their own license
# to the complete work.
#
# Copyright (c) Ansible Inc, 2015
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without modification,
# are permitted provided that the following conditions are met:
#
# * Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# * Redistributions in binary form must reproduce the above copyright notice,
# this list of conditions and the following disclaimer in the documentation
# and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
# IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
# PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
# USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#
import platform
import os
import shlex
import select
import subprocess
import json
class Service(object):
"""
This is the generic Service manipulation class that is subclassed based on system.
A subclass should override the following methods:
- action
- enable
- status
"""
def __init__(self, module):
# states
self.running = None
self.enabled = None
self.action = None
# outcome
self.changed = False
# options
self.module = module
# alias running to started
if self.module.params['state'] == 'running':
self.module.params['state'] = 'started'
# ===========================================
# Platform specific methods (must be replaced by subclass).
def action(self):
self.module.fail_json(msg="action not implemented on target service")
def status(self): # this should also set self.enabled
self.module.fail_json(msg="status not implemented on target service")
def enable(self):
self.module.fail_json(msg="enable not implemented on target service")
# ===========================================
# Generic methods that should be used on all services.
def execute_command(self, cmd, daemonize=False):
# Most things don't need to be daemonized
if not daemonize:
return self.module.run_command(cmd)
# This is complex because daemonization is hard for people.
# What we do is daemonize a part of this module, the daemon runs the
# command, picks up the return code and output, and returns it to the
# main process.
pipe = os.pipe()
pid = os.fork()
if pid == 0:
os.close(pipe[0])
# Set stdin/stdout/stderr to /dev/null
fd = os.open(os.devnull, os.O_RDWR)
if fd != 0:
os.dup2(fd, 0)
if fd != 1:
os.dup2(fd, 1)
if fd != 2:
os.dup2(fd, 2)
if fd not in (0, 1, 2):
os.close(fd)
# Make us a daemon. Yes, that's all it takes.
pid = os.fork()
if pid > 0:
os._exit(0)
os.setsid()
os.chdir("/")
pid = os.fork()
if pid > 0:
os._exit(0)
# Start the command
if isinstance(cmd, basestring):
cmd = shlex.split(cmd)
p = subprocess.Popen(cmd, shell=False, stdout=subprocess.PIPE, stderr=subprocess.PIPE, preexec_fn=lambda: os.close(pipe[1]))
stdout = ""
stderr = ""
fds = [p.stdout, p.stderr]
# Wait for all output, or until the main process is dead and its output is done.
while fds:
rfd, wfd, efd = select.select(fds, [], fds, 1)
if not (rfd + wfd + efd) and p.poll() is not None:
break
if p.stdout in rfd:
dat = os.read(p.stdout.fileno(), 4096)
if not dat:
fds.remove(p.stdout)
stdout += dat
if p.stderr in rfd:
dat = os.read(p.stderr.fileno(), 4096)
if not dat:
fds.remove(p.stderr)
stderr += dat
p.wait()
# Return a JSON blob to parent
os.write(pipe[1], json.dumps([p.returncode, stdout, stderr]))
os.close(pipe[1])
os._exit(0)
elif pid == -1:
self.module.fail_json(msg="unable to fork")
else:
os.close(pipe[1])
os.waitpid(pid, 0)
# Wait for data from daemon process and process it.
data = ""
while True:
rfd, wfd, efd = select.select([pipe[0]], [], [pipe[0]])
if pipe[0] in rfd:
dat = os.read(pipe[0], 4096)
if not dat:
break
data += dat
return json.loads(data)
def check_ps(self):
running = False
# Set ps flags
if platform.system() == 'SunOS':
psflags = '-ef'
else:
psflags = 'auxww'
# Find ps binary
psbin = self.module.get_bin_path('ps', True)
(rc, psout, pserr) = self.execute_command('%s %s' % (psbin, psflags))
# If rc is 0, set running as appropriate
if rc == 0:
lines = psout.split("\n")
for line in lines:
if self.module.params['pattern'] in line and not "pattern=" in line:
# so as to not confuse ./hacking/test-module
running = True
break
self.running = running
def result(self, msg=''):
return {
'name': self.module.name,
'state': self.status(),
'enabled': self.enabled,
'changed': self.changed,
'msg': msg,
}
def run(self):
if self.module.params['state'] is None and self.module.params['enabled'] is None:
self.module.fail_json(msg="Neither 'state' nor 'enabled' set")
# Set service startup state on request
if self.module.params['enabled'] is not None and self.enabled != self.module.params['enabled']:
self.changed = True
if not self.module.check_mode:
self.enable()
if self.module.params['state'] is not None and self.module.params['state'] != self.status():
self.changed = True
if not self.module.check_mode:
self.action()
return self.result()
def service_shared_arg_spec():
return dict(
name = dict(required=True),
state = dict(choices=['running', 'started', 'stopped', 'restarted', 'reloaded']),
enabled = dict(type='bool'),
)
# these are only needed/useful in init/rc systems
#arguments = dict(aliases=['args'], default=''),
#pattern = dict(required=False, default=None),
#sleep = dict(required=False, type='int', default=None),
#runlevel = dict(required=False, default='default'),