community.general/lib/ansible/inventory.py
Seth Vidal dc35dd99c0 inventory group 'all' variables are global variables
applied to every host and available all over
they are read in so that ones defined first can be used to define
the later ones.
2012-05-02 18:30:58 -04:00

327 lines
12 KiB
Python

# (c) 2012, Michael DeHaan <michael.dehaan@gmail.com>
#
# 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 fnmatch
import os
import subprocess
import constants as C
from ansible import errors
from ansible import utils
class Inventory(object):
""" Host inventory for ansible.
The inventory is either a simple text file with systems and [groups] of
systems, or a script that will be called with --list or --host.
"""
def __init__(self, host_list=C.DEFAULT_HOST_LIST, global_host_vars={}):
self._restriction = None
self._variables = {}
self._global_host_vars = global_host_vars # lets us pass in a global var list
# that each host gets
# after we have set up the inventory
# to get all group variables
if type(host_list) == list:
self.host_list = host_list
self.groups = dict(ungrouped=host_list)
self._is_script = False
return
inventory_file = os.path.expanduser(host_list)
if not os.path.exists(inventory_file):
raise errors.AnsibleFileNotFound("inventory file not found: %s" % host_list)
self.inventory_file = os.path.abspath(inventory_file)
if os.access(self.inventory_file, os.X_OK):
self.host_list, self.groups = self._parse_from_script()
self._is_script = True
else:
self.host_list, self.groups = self._parse_from_file()
self._is_script = False
# *****************************************************
# Public API
def list_hosts(self, pattern="all"):
""" Return a list of hosts [matching the pattern] """
if self._restriction is None:
host_list = self.host_list
else:
host_list = [ h for h in self.host_list if h in self._restriction ]
return [ h for h in host_list if self._matches(h, pattern) ]
def restrict_to(self, restriction):
""" Restrict list operations to the hosts given in restriction """
if type(restriction)!=list:
restriction = [ restriction ]
self._restriction = restriction
def lift_restriction(self):
""" Do not restrict list operations """
self._restriction = None
def get_variables(self, host):
""" Return the variables associated with this host. """
variables = {
'inventory_hostname': host,
}
if host in self._variables:
variables.update(self._variables[host].copy())
if self._is_script:
variables.update(self._get_variables_from_script(host))
variables['group_names'] = []
for name,hosts in self.groups.iteritems():
if host in hosts:
variables['group_names'].append(name)
return variables
def get_global_vars(self):
return self._global_host_vars
# *****************************************************
def _parse_from_file(self):
''' parse a textual host file '''
results = []
groups = dict(ungrouped=[])
lines = file(self.inventory_file).read().split("\n")
if "---" in lines:
return self._parse_yaml()
group_name = 'ungrouped'
for item in lines:
item = item.lstrip().rstrip()
if item.startswith("#"):
# ignore commented out lines
pass
elif item.startswith("["):
# looks like a group
group_name = item.replace("[","").replace("]","").lstrip().rstrip()
groups[group_name] = []
elif item != "":
# looks like a regular host
if ":" in item:
# a port was specified
item, port = item.split(":")
try:
port = int(port)
except ValueError:
raise errors.AnsibleError("SSH port for %s in inventory (%s) should be numerical."%(item, port))
self._set_variable(item, "ansible_ssh_port", port)
groups[group_name].append(item)
if not item in results:
results.append(item)
return (results, groups)
# *****************************************************
def _parse_from_script(self):
''' evaluate a script that returns list of hosts by groups '''
results = []
groups = dict(ungrouped=[])
cmd = [self.inventory_file, '--list']
try:
cmd = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, shell=False)
out, err = cmd.communicate()
except Exception, e:
raise errors.AnsibleError("Failure executing %s to produce host list:\n %s" % (self.inventory_file, str(e)))
rc = cmd.returncode
if rc:
raise errors.AnsibleError("%s: %s" % self.inventory_file, err)
try:
groups = utils.json_loads(out)
except:
raise errors.AnsibleError("invalid JSON response from script: %s" % self.inventory_file)
for (groupname, hostlist) in groups.iteritems():
for host in hostlist:
if host not in results:
results.append(host)
return (results, groups)
# *****************************************************
def _parse_yaml(self):
""" Load the inventory from a yaml file.
returns hosts and groups"""
data = utils.parse_yaml_from_file(self.inventory_file)
if type(data) != list:
raise errors.AnsibleError("YAML inventory should be a list.")
hosts = []
groups = {}
ungrouped = []
# go through once and grab up the global_host_vars from the 'all' group
for item in data:
if type(item) == dict:
if "group" in item and 'all' == item["group"]:
if "vars" in item:
variables = item['vars']
if type(variables) == list:
for variable in variables:
if len(variable) != 1:
raise errors.AnsibleError("Only one item expected in %s"%(variable))
k, v = variable.items()[0]
self._global_host_vars[k] = utils.template(v, self._global_host_vars, {})
elif type(variables) == dict:
self._global_host_vars.update(variables)
for item in data:
if type(item) == dict:
if "group" in item:
group_name = item["group"]
group_vars = []
if "vars" in item:
group_vars.extend(item["vars"])
group_hosts = []
if "hosts" in item:
for host in item["hosts"]:
host_name = self._parse_yaml_host(host, group_vars)
group_hosts.append(host_name)
groups[group_name] = group_hosts
hosts.extend(group_hosts)
elif "host" in item:
host_name = self._parse_yaml_host(item)
hosts.append(host_name)
ungrouped.append(host_name)
else:
host_name = self._parse_yaml_host(item)
hosts.append(host_name)
ungrouped.append(host_name)
# filter duplicate hosts
output_hosts = []
for host in hosts:
if host not in output_hosts:
output_hosts.append(host)
if len(ungrouped) > 0 :
# hosts can be defined top-level, but also in a group
really_ungrouped = []
for host in ungrouped:
already_grouped = False
for name, group_hosts in groups.items():
if host in group_hosts:
already_grouped = True
if not already_grouped:
really_ungrouped.append(host)
groups["ungrouped"] = really_ungrouped
return output_hosts, groups
def _parse_yaml_host(self, item, variables=[]):
def set_variables(host, variables):
if type(variables) == list:
for variable in variables:
if len(variable) != 1:
raise errors.AnsibleError("Only one item expected in %s"%(variable))
k, v = variable.items()[0]
self._set_variable(host, k, v)
elif type(variables) == dict:
for k, v in variables.iteritems():
self._set_variable(host, k, v)
if type(item) in [str, unicode]:
set_variables(item, variables)
return item
elif type(item) == dict:
if "host" in item:
host_name = item["host"]
set_variables(host_name, variables)
if "vars" in item:
set_variables(host_name, item["vars"])
return host_name
else:
raise errors.AnsibleError("Unknown item in inventory: %s"%(item))
def _get_variables_from_script(self, host):
''' support per system variabes from external variable scripts, see web docs '''
cmd = [self.inventory_file, '--host', host]
cmd = subprocess.Popen(cmd,
stdout=subprocess.PIPE,
stderr=subprocess.PIPE,
shell=False
)
out, err = cmd.communicate()
variables = {}
try:
variables = utils.json_loads(out)
except:
raise errors.AnsibleError("%s returned invalid result when called with hostname %s" % (
self.inventory_file,
host
))
return variables
def _set_variable(self, host, key, value):
if not host in self._variables:
self._variables[host] = {}
self._variables[host][key] = value
def _matches(self, host_name, pattern):
''' returns if a hostname is matched by the pattern '''
# a pattern is in fnmatch format but more than one pattern
# can be strung together with semicolons. ex:
# atlanta-web*.example.com;dc-web*.example.com
if host_name == '':
return False
pattern = pattern.replace(";",":")
subpatterns = pattern.split(":")
for subpattern in subpatterns:
if subpattern == 'all':
return True
if fnmatch.fnmatch(host_name, subpattern):
return True
elif subpattern in self.groups:
if host_name in self.groups[subpattern]:
return True
return False