ansible/lib/ansible/inventory/manager.py
Rick Elrod 9579113941 Remove some no-op code from InventoryManager
Change:
- Remove some no-op code
- Split up a somewhat complex line into two lines
- Nuke an incorrect comment

Test Plan:
CI

Signed-off-by: Rick Elrod <rick@elrod.me>
2020-05-07 21:42:48 -05:00

641 lines
25 KiB
Python

# (c) 2012-2014, 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/>.
#############################################
from __future__ import (absolute_import, division, print_function)
__metaclass__ = type
import fnmatch
import os
import sys
import re
import itertools
import traceback
from operator import attrgetter
from random import shuffle
from ansible import constants as C
from ansible.errors import AnsibleError, AnsibleOptionsError, AnsibleParserError
from ansible.inventory.data import InventoryData
from ansible.module_utils.six import string_types
from ansible.module_utils._text import to_bytes, to_text
from ansible.parsing.utils.addresses import parse_address
from ansible.plugins.loader import inventory_loader
from ansible.utils.helpers import deduplicate_list
from ansible.utils.path import unfrackpath
from ansible.utils.display import Display
from ansible.utils.vars import combine_vars
from ansible.vars.plugins import get_vars_from_inventory_sources
display = Display()
IGNORED_ALWAYS = [br"^\.", b"^host_vars$", b"^group_vars$", b"^vars_plugins$"]
IGNORED_PATTERNS = [to_bytes(x) for x in C.INVENTORY_IGNORE_PATTERNS]
IGNORED_EXTS = [b'%s$' % to_bytes(re.escape(x)) for x in C.INVENTORY_IGNORE_EXTS]
IGNORED = re.compile(b'|'.join(IGNORED_ALWAYS + IGNORED_PATTERNS + IGNORED_EXTS))
PATTERN_WITH_SUBSCRIPT = re.compile(
r'''^
(.+) # A pattern expression ending with...
\[(?: # A [subscript] expression comprising:
(-?[0-9]+)| # A single positive or negative number
([0-9]+)([:-]) # Or an x:y or x: range.
([0-9]*)
)\]
$
''', re.X
)
def order_patterns(patterns):
''' takes a list of patterns and reorders them by modifier to apply them consistently '''
# FIXME: this goes away if we apply patterns incrementally or by groups
pattern_regular = []
pattern_intersection = []
pattern_exclude = []
for p in patterns:
if not p:
continue
if p[0] == "!":
pattern_exclude.append(p)
elif p[0] == "&":
pattern_intersection.append(p)
else:
pattern_regular.append(p)
# if no regular pattern was given, hence only exclude and/or intersection
# make that magically work
if pattern_regular == []:
pattern_regular = ['all']
# when applying the host selectors, run those without the "&" or "!"
# first, then the &s, then the !s.
return pattern_regular + pattern_intersection + pattern_exclude
def split_host_pattern(pattern):
"""
Takes a string containing host patterns separated by commas (or a list
thereof) and returns a list of single patterns (which may not contain
commas). Whitespace is ignored.
Also accepts ':' as a separator for backwards compatibility, but it is
not recommended due to the conflict with IPv6 addresses and host ranges.
Example: 'a,b[1], c[2:3] , d' -> ['a', 'b[1]', 'c[2:3]', 'd']
"""
if isinstance(pattern, list):
results = (split_host_pattern(p) for p in pattern)
# flatten the results
return list(itertools.chain.from_iterable(results))
elif not isinstance(pattern, string_types):
pattern = to_text(pattern, errors='surrogate_or_strict')
# If it's got commas in it, we'll treat it as a straightforward
# comma-separated list of patterns.
if u',' in pattern:
patterns = pattern.split(u',')
# If it doesn't, it could still be a single pattern. This accounts for
# non-separator uses of colons: IPv6 addresses and [x:y] host ranges.
else:
try:
(base, port) = parse_address(pattern, allow_ranges=True)
patterns = [pattern]
except Exception:
# The only other case we accept is a ':'-separated list of patterns.
# This mishandles IPv6 addresses, and is retained only for backwards
# compatibility.
patterns = re.findall(
to_text(r'''(?: # We want to match something comprising:
[^\s:\[\]] # (anything other than whitespace or ':[]'
| # ...or...
\[[^\]]*\] # a single complete bracketed expression)
)+ # occurring once or more
'''), pattern, re.X
)
return [p.strip() for p in patterns if p.strip()]
class InventoryManager(object):
''' Creates and manages inventory '''
def __init__(self, loader, sources=None):
# base objects
self._loader = loader
self._inventory = InventoryData()
# a list of host(names) to contain current inquiries to
self._restriction = None
self._subset = None
# caches
self._hosts_patterns_cache = {} # resolved full patterns
self._pattern_cache = {} # resolved individual patterns
# the inventory dirs, files, script paths or lists of hosts
if sources is None:
self._sources = []
elif isinstance(sources, string_types):
self._sources = [sources]
else:
self._sources = sources
# get to work!
self.parse_sources(cache=True)
@property
def localhost(self):
return self._inventory.localhost
@property
def groups(self):
return self._inventory.groups
@property
def hosts(self):
return self._inventory.hosts
def add_host(self, host, group=None, port=None):
return self._inventory.add_host(host, group, port)
def add_group(self, group):
return self._inventory.add_group(group)
def get_groups_dict(self):
return self._inventory.get_groups_dict()
def reconcile_inventory(self):
self.clear_caches()
return self._inventory.reconcile_inventory()
def get_host(self, hostname):
return self._inventory.get_host(hostname)
def _fetch_inventory_plugins(self):
''' sets up loaded inventory plugins for usage '''
display.vvvv('setting up inventory plugins')
plugins = []
for name in C.INVENTORY_ENABLED:
plugin = inventory_loader.get(name)
if plugin:
plugins.append(plugin)
else:
display.warning('Failed to load inventory plugin, skipping %s' % name)
if not plugins:
raise AnsibleError("No inventory plugins available to generate inventory, make sure you have at least one whitelisted.")
return plugins
def parse_sources(self, cache=False):
''' iterate over inventory sources and parse each one to populate it'''
parsed = False
# allow for multiple inventory parsing
for source in self._sources:
if source:
if ',' not in source:
source = unfrackpath(source, follow=False)
parse = self.parse_source(source, cache=cache)
if parse and not parsed:
parsed = True
if parsed:
# do post processing
self._inventory.reconcile_inventory()
else:
if C.INVENTORY_UNPARSED_IS_FAILED:
raise AnsibleError("No inventory was parsed, please check your configuration and options.")
else:
display.warning("No inventory was parsed, only implicit localhost is available")
for group in self.groups.values():
group.vars = combine_vars(group.vars, get_vars_from_inventory_sources(self._loader, self._sources, [group], 'inventory'))
for host in self.hosts.values():
host.vars = combine_vars(host.vars, get_vars_from_inventory_sources(self._loader, self._sources, [host], 'inventory'))
def parse_source(self, source, cache=False):
''' Generate or update inventory for the source provided '''
parsed = False
display.debug(u'Examining possible inventory source: %s' % source)
# use binary for path functions
b_source = to_bytes(source)
# process directories as a collection of inventories
if os.path.isdir(b_source):
display.debug(u'Searching for inventory files in directory: %s' % source)
for i in sorted(os.listdir(b_source)):
display.debug(u'Considering %s' % i)
# Skip hidden files and stuff we explicitly ignore
if IGNORED.search(i):
continue
# recursively deal with directory entries
fullpath = to_text(os.path.join(b_source, i), errors='surrogate_or_strict')
parsed_this_one = self.parse_source(fullpath, cache=cache)
display.debug(u'parsed %s as %s' % (fullpath, parsed_this_one))
if not parsed:
parsed = parsed_this_one
else:
# left with strings or files, let plugins figure it out
# set so new hosts can use for inventory_file/dir vars
self._inventory.current_source = source
# try source with each plugin
failures = []
for plugin in self._fetch_inventory_plugins():
plugin_name = to_text(getattr(plugin, '_load_name', getattr(plugin, '_original_path', '')))
display.debug(u'Attempting to use plugin %s (%s)' % (plugin_name, plugin._original_path))
# initialize and figure out if plugin wants to attempt parsing this file
try:
plugin_wants = bool(plugin.verify_file(source))
except Exception:
plugin_wants = False
if plugin_wants:
try:
# FIXME in case plugin fails 1/2 way we have partial inventory
plugin.parse(self._inventory, self._loader, source, cache=cache)
try:
plugin.update_cache_if_changed()
except AttributeError:
# some plugins might not implement caching
pass
parsed = True
display.vvv('Parsed %s inventory source with %s plugin' % (source, plugin_name))
break
except AnsibleParserError as e:
display.debug('%s was not parsable by %s' % (source, plugin_name))
tb = ''.join(traceback.format_tb(sys.exc_info()[2]))
failures.append({'src': source, 'plugin': plugin_name, 'exc': e, 'tb': tb})
except Exception as e:
display.debug('%s failed while attempting to parse %s' % (plugin_name, source))
tb = ''.join(traceback.format_tb(sys.exc_info()[2]))
failures.append({'src': source, 'plugin': plugin_name, 'exc': AnsibleError(e), 'tb': tb})
else:
display.vvv("%s declined parsing %s as it did not pass its verify_file() method" % (plugin_name, source))
else:
if not parsed and failures:
# only if no plugin processed files should we show errors.
for fail in failures:
display.warning(u'\n* Failed to parse %s with %s plugin: %s' % (to_text(fail['src']), fail['plugin'], to_text(fail['exc'])))
if 'tb' in fail:
display.vvv(to_text(fail['tb']))
if C.INVENTORY_ANY_UNPARSED_IS_FAILED:
raise AnsibleError(u'Completely failed to parse inventory source %s' % (source))
if not parsed:
if source != '/etc/ansible/hosts' or os.path.exists(source):
# only warn if NOT using the default and if using it, only if the file is present
display.warning("Unable to parse %s as an inventory source" % source)
# clear up, jic
self._inventory.current_source = None
return parsed
def clear_caches(self):
''' clear all caches '''
self._hosts_patterns_cache = {}
self._pattern_cache = {}
# FIXME: flush inventory cache
def refresh_inventory(self):
''' recalculate inventory '''
self.clear_caches()
self._inventory = InventoryData()
self.parse_sources(cache=False)
def _match_list(self, items, pattern_str):
# compile patterns
try:
if not pattern_str[0] == '~':
pattern = re.compile(fnmatch.translate(pattern_str))
else:
pattern = re.compile(pattern_str[1:])
except Exception:
raise AnsibleError('Invalid host list pattern: %s' % pattern_str)
# apply patterns
results = []
for item in items:
if pattern.match(item):
results.append(item)
return results
def get_hosts(self, pattern="all", ignore_limits=False, ignore_restrictions=False, order=None):
"""
Takes a pattern or list of patterns and returns a list of matching
inventory host names, taking into account any active restrictions
or applied subsets
"""
hosts = []
# Check if pattern already computed
if isinstance(pattern, list):
pattern_list = pattern[:]
else:
pattern_list = [pattern]
if pattern_list:
if not ignore_limits and self._subset:
pattern_list.extend(self._subset)
if not ignore_restrictions and self._restriction:
pattern_list.extend(self._restriction)
# This is only used as a hash key in the self._hosts_patterns_cache dict
# a tuple is faster than stringifying
pattern_hash = tuple(pattern_list)
if pattern_hash not in self._hosts_patterns_cache:
patterns = split_host_pattern(pattern)
hosts = self._evaluate_patterns(patterns)
# mainly useful for hostvars[host] access
if not ignore_limits and self._subset:
# exclude hosts not in a subset, if defined
subset_uuids = set(s._uuid for s in self._evaluate_patterns(self._subset))
hosts = [h for h in hosts if h._uuid in subset_uuids]
if not ignore_restrictions and self._restriction:
# exclude hosts mentioned in any restriction (ex: failed hosts)
hosts = [h for h in hosts if h.name in self._restriction]
self._hosts_patterns_cache[pattern_hash] = deduplicate_list(hosts)
# sort hosts list if needed (should only happen when called from strategy)
if order in ['sorted', 'reverse_sorted']:
hosts = sorted(self._hosts_patterns_cache[pattern_hash][:], key=attrgetter('name'), reverse=(order == 'reverse_sorted'))
elif order == 'reverse_inventory':
hosts = self._hosts_patterns_cache[pattern_hash][::-1]
else:
hosts = self._hosts_patterns_cache[pattern_hash][:]
if order == 'shuffle':
shuffle(hosts)
elif order not in [None, 'inventory']:
raise AnsibleOptionsError("Invalid 'order' specified for inventory hosts: %s" % order)
return hosts
def _evaluate_patterns(self, patterns):
"""
Takes a list of patterns and returns a list of matching host names,
taking into account any negative and intersection patterns.
"""
patterns = order_patterns(patterns)
hosts = []
for p in patterns:
# avoid resolving a pattern that is a plain host
if p in self._inventory.hosts:
hosts.append(self._inventory.get_host(p))
else:
that = self._match_one_pattern(p)
if p[0] == "!":
that = set(that)
hosts = [h for h in hosts if h not in that]
elif p[0] == "&":
that = set(that)
hosts = [h for h in hosts if h in that]
else:
existing_hosts = set(y.name for y in hosts)
hosts.extend([h for h in that if h.name not in existing_hosts])
return hosts
def _match_one_pattern(self, pattern):
"""
Takes a single pattern and returns a list of matching host names.
Ignores intersection (&) and exclusion (!) specifiers.
The pattern may be:
1. A regex starting with ~, e.g. '~[abc]*'
2. A shell glob pattern with ?/*/[chars]/[!chars], e.g. 'foo*'
3. An ordinary word that matches itself only, e.g. 'foo'
The pattern is matched using the following rules:
1. If it's 'all', it matches all hosts in all groups.
2. Otherwise, for each known group name:
(a) if it matches the group name, the results include all hosts
in the group or any of its children.
(b) otherwise, if it matches any hosts in the group, the results
include the matching hosts.
This means that 'foo*' may match one or more groups (thus including all
hosts therein) but also hosts in other groups.
The built-in groups 'all' and 'ungrouped' are special. No pattern can
match these group names (though 'all' behaves as though it matches, as
described above). The word 'ungrouped' can match a host of that name,
and patterns like 'ungr*' and 'al*' can match either hosts or groups
other than all and ungrouped.
If the pattern matches one or more group names according to these rules,
it may have an optional range suffix to select a subset of the results.
This is allowed only if the pattern is not a regex, i.e. '~foo[1]' does
not work (the [1] is interpreted as part of the regex), but 'foo*[1]'
would work if 'foo*' matched the name of one or more groups.
Duplicate matches are always eliminated from the results.
"""
if pattern[0] in ("&", "!"):
pattern = pattern[1:]
if pattern not in self._pattern_cache:
(expr, slice) = self._split_subscript(pattern)
hosts = self._enumerate_matches(expr)
try:
hosts = self._apply_subscript(hosts, slice)
except IndexError:
raise AnsibleError("No hosts matched the subscripted pattern '%s'" % pattern)
self._pattern_cache[pattern] = hosts
return self._pattern_cache[pattern]
def _split_subscript(self, pattern):
"""
Takes a pattern, checks if it has a subscript, and returns the pattern
without the subscript and a (start,end) tuple representing the given
subscript (or None if there is no subscript).
Validates that the subscript is in the right syntax, but doesn't make
sure the actual indices make sense in context.
"""
# Do not parse regexes for enumeration info
if pattern[0] == '~':
return (pattern, None)
# We want a pattern followed by an integer or range subscript.
# (We can't be more restrictive about the expression because the
# fnmatch semantics permit [\[:\]] to occur.)
subscript = None
m = PATTERN_WITH_SUBSCRIPT.match(pattern)
if m:
(pattern, idx, start, sep, end) = m.groups()
if idx:
subscript = (int(idx), None)
else:
if not end:
end = -1
subscript = (int(start), int(end))
if sep == '-':
display.warning("Use [x:y] inclusive subscripts instead of [x-y] which has been removed")
return (pattern, subscript)
def _apply_subscript(self, hosts, subscript):
"""
Takes a list of hosts and a (start,end) tuple and returns the subset of
hosts based on the subscript (which may be None to return all hosts).
"""
if not hosts or not subscript:
return hosts
(start, end) = subscript
if end:
if end == -1:
end = len(hosts) - 1
return hosts[start:end + 1]
else:
return [hosts[start]]
def _enumerate_matches(self, pattern):
"""
Returns a list of host names matching the given pattern according to the
rules explained above in _match_one_pattern.
"""
results = []
# check if pattern matches group
matching_groups = self._match_list(self._inventory.groups, pattern)
if matching_groups:
for groupname in matching_groups:
results.extend(self._inventory.groups[groupname].get_hosts())
# check hosts if no groups matched or it is a regex/glob pattern
if not matching_groups or pattern[0] == '~' or any(special in pattern for special in ('.', '?', '*', '[')):
# pattern might match host
matching_hosts = self._match_list(self._inventory.hosts, pattern)
if matching_hosts:
for hostname in matching_hosts:
results.append(self._inventory.hosts[hostname])
if not results and pattern in C.LOCALHOST:
# get_host autocreates implicit when needed
implicit = self._inventory.get_host(pattern)
if implicit:
results.append(implicit)
# Display warning if specified host pattern did not match any groups or hosts
if not results and not matching_groups and pattern != 'all':
msg = "Could not match supplied host pattern, ignoring: %s" % pattern
display.debug(msg)
if C.HOST_PATTERN_MISMATCH == 'warning':
display.warning(msg)
elif C.HOST_PATTERN_MISMATCH == 'error':
raise AnsibleError(msg)
# no need to write 'ignore' state
return results
def list_hosts(self, pattern="all"):
""" return a list of hostnames for a pattern """
# FIXME: cache?
result = self.get_hosts(pattern)
# allow implicit localhost if pattern matches and no other results
if len(result) == 0 and pattern in C.LOCALHOST:
result = [pattern]
return result
def list_groups(self):
# FIXME: cache?
return sorted(self._inventory.groups.keys())
def restrict_to_hosts(self, restriction):
"""
Restrict list operations to the hosts given in restriction. This is used
to batch serial operations in main playbook code, don't use this for other
reasons.
"""
if restriction is None:
return
elif not isinstance(restriction, list):
restriction = [restriction]
self._restriction = set(to_text(h.name) for h in restriction)
def subset(self, subset_pattern):
"""
Limits inventory results to a subset of inventory that matches a given
pattern, such as to select a given geographic of numeric slice amongst
a previous 'hosts' selection that only select roles, or vice versa.
Corresponds to --limit parameter to ansible-playbook
"""
if subset_pattern is None:
self._subset = None
else:
subset_patterns = split_host_pattern(subset_pattern)
results = []
# allow Unix style @filename data
for x in subset_patterns:
if not x:
continue
if x[0] == "@":
b_limit_file = to_bytes(x[1:])
if not os.path.exists(b_limit_file):
raise AnsibleError(u'Unable to find limit file %s' % b_limit_file)
with open(b_limit_file) as fd:
results.extend([to_text(l.strip()) for l in fd.read().split("\n")])
else:
results.append(to_text(x))
self._subset = results
def remove_restriction(self):
""" Do not restrict list operations """
self._restriction = None
def clear_pattern_cache(self):
self._pattern_cache = {}