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cdist-mirror/bin/cdist

788 lines
27 KiB

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
#
# 2010-2011 Nico Schottelius (nico-cdist at schottelius.org)
#
# This file is part of cdist.
#
# cdist 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.
#
# cdist 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 cdist. If not, see <http://www.gnu.org/licenses/>.
#
#
import argparse
import datetime
import logging
import multiprocessing
import os
import re
import subprocess
import shutil
import stat
import sys
import tempfile
BANNER = """
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.udR88N ^"*8888N .@88u .@^%8888" -*8888888
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9888 'Y" 888E 888E 888E 8888N=*8888 8888
9888 888E 888E 888E %8" R88 8888
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?8888u../ .888N..888 888& .888888P` ^%888*
"8888P' `"888*"" R888" ` ^"F 'Y"
"P' "" ""
"""
# Given paths from installation
REMOTE_BASE_DIR = "/var/lib/cdist"
REMOTE_CONF_DIR = os.path.join(REMOTE_BASE_DIR, "conf")
REMOTE_OBJECT_DIR = os.path.join(REMOTE_BASE_DIR, "object")
REMOTE_TYPE_DIR = os.path.join(REMOTE_CONF_DIR, "type")
REMOTE_GLOBAL_EXPLORER_DIR = os.path.join(REMOTE_CONF_DIR, "explorer")
CODE_HEADER = "#!/bin/sh -e\n"
DOT_CDIST = ".cdist"
TYPE_PREFIX = "__"
VERSION = "2.0.1"
logging.basicConfig(level=logging.INFO, format='%(levelname)s: %(message)s')
log = logging.getLogger()
def file_to_list(filename):
"""Return list from \n seperated file"""
if os.path.isfile(filename):
file_fd = open(filename, "r")
lines = file_fd.readlines()
file_fd.close()
# Remove \n from all lines
lines = map(lambda s: s.strip(), lines)
else:
lines = []
return lines
def exit_error(*args):
log.error(*args)
sys.exit(1)
class Cdist:
"""Cdist main class to hold arbitrary data"""
def __init__(self, target_host,
initial_manifest=False, remote_user="root",
home=None, debug=False):
self.target_host = target_host
self.remote_prefix = ["ssh", "root@" + self.target_host]
# Setup directory paths
self.temp_dir = tempfile.mkdtemp()
self.debug = debug
if home:
self.base_dir = home
else:
self.base_dir = os.path.abspath(os.path.join(os.path.dirname(__file__), os.pardir))
self.conf_dir = os.path.join(self.base_dir, "conf")
self.cache_base_dir = os.path.join(self.base_dir, "cache")
self.cache_dir = os.path.join(self.cache_base_dir, self.target_host)
self.global_explorer_dir = os.path.join(self.conf_dir, "explorer")
self.lib_dir = os.path.join(self.base_dir, "lib")
self.manifest_dir = os.path.join(self.conf_dir, "manifest")
self.type_base_dir = os.path.join(self.conf_dir, "type")
self.out_dir = os.path.join(self.temp_dir, "out")
os.mkdir(self.out_dir)
self.global_explorer_out_dir = os.path.join(self.out_dir, "explorer")
os.mkdir(self.global_explorer_out_dir)
self.object_base_dir = os.path.join(self.out_dir, "object")
# Setup binary directory + contents
self.bin_dir = os.path.join(self.out_dir, "bin")
os.mkdir(self.bin_dir)
self.link_type_to_emulator()
# List of type explorers transferred
self.type_explorers_transferred = {}
# objects
self.objects_prepared = []
self.remote_user = remote_user
# Mostly static, but can be overwritten on user demand
if initial_manifest:
self.initial_manifest = initial_manifest
else:
self.initial_manifest = os.path.join(self.manifest_dir, "init")
def cleanup(self):
# Do not use in __del__:
# http://docs.python.org/reference/datamodel.html#customization
# "other globals referenced by the __del__() method may already have been deleted
# or in the process of being torn down (e.g. the import machinery shutting down)"
#
log.debug("Saving" + self.temp_dir + "to " + self.cache_dir)
# Remove previous cache
if os.path.exists(self.cache_dir):
shutil.rmtree(self.cache_dir)
shutil.move(self.temp_dir, self.cache_dir)
def remote_mkdir(self, directory):
"""Create directory on remote side"""
self.run_or_fail(["mkdir", "-p", directory], remote=True)
def remote_cat(filename):
"""Use cat on the remote side for output"""
self.run_or_fail(["cat", filename], remote=True)
def shell_run_or_debug_fail(self, script, *args, **kargs):
# Manually execute /bin/sh, because sh -e does what we want
# and sh -c -e does not exit if /bin/false called
args[0][:0] = [ "/bin/sh", "-e" ]
remote = False
if "remote" in kargs:
if kargs["remote"]:
args[0][:0] = self.remote_prefix
remote = true
del kargs["remote"]
log.debug("Shell exec cmd: %s", args)
log.debug("Shell exec env: %s", kargs['env'])
try:
subprocess.check_call(*args, **kargs)
except subprocess.CalledProcessError:
log.error("Code that raised the error:\n")
if remote:
remote_cat(script)
else:
script_fd = open(script)
print(script_fd.read())
script_fd.close()
exit_error("Command failed (shell): " + " ".join(*args))
except OSError as error:
exit_error(" ".join(*args) + ": " + error.args[1])
def run_or_fail(self, *args, **kargs):
if "remote" in kargs:
if kargs["remote"]:
args[0][:0] = self.remote_prefix
del kargs["remote"]
log.debug("Exec: " + " ".join(*args))
try:
subprocess.check_call(*args, **kargs)
except subprocess.CalledProcessError:
exit_error("Command failed: " + " ".join(*args))
except OSError as error:
exit_error(" ".join(*args) + ": " + error.args[1])
def remove_remote_dir(self, destination):
self.run_or_fail(["rm", "-rf", destination], remote=True)
def transfer_dir(self, source, destination):
"""Transfer directory and previously delete the remote destination"""
self.remove_remote_dir(destination)
self.run_or_fail(["scp", "-qr", source,
self.remote_user + "@" +
self.target_host + ":" +
destination])
def transfer_file(self, source, destination):
"""Transfer file"""
self.run_or_fail(["scp", "-q", source,
self.remote_user + "@" +
self.target_host + ":" +
destination])
def global_explorer_output_path(self, explorer):
"""Returns path of the output for a global explorer"""
return os.path.join(self.global_explorer_out_dir, explorer)
def type_explorer_output_dir(self, cdist_object):
"""Returns and creates dir of the output for a type explorer"""
dir = os.path.join(self.object_dir(cdist_object), "explorer")
if not os.path.isdir(dir):
os.mkdir(dir)
return dir
def remote_global_explorer_path(self, explorer):
"""Returns path to the remote explorer"""
return os.path.join(REMOTE_GLOBAL_EXPLORER_DIR, explorer)
def list_global_explorers(self):
"""Return list of available explorers"""
return os.listdir(self.global_explorer_dir)
def list_type_explorers(self, type):
"""Return list of available explorers for a specific type"""
dir = self.type_dir(type, "explorer")
if os.path.isdir(dir):
list = os.listdir(dir)
else:
list = []
log.debug("Explorers for %s in %s: %s", type, dir, list)
return list
def list_types(self):
return os.listdir(self.type_base_dir)
def list_object_paths(self, starting_point):
"""Return list of paths of existing objects"""
object_paths = []
for content in os.listdir(starting_point):
full_path = os.path.join(starting_point, content)
if os.path.isdir(full_path):
object_paths.extend(self.list_object_paths(starting_point = full_path))
# Directory contains .cdist -> is an object
if content == DOT_CDIST:
object_paths.append(starting_point)
return object_paths
def get_type_from_object(self, cdist_object):
"""Returns the first part (i.e. type) of an object"""
return cdist_object.split(os.sep)[0]
def get_object_id_from_object(self, cdist_object):
"""Returns everything but the first part (i.e. object_id) of an object"""
return os.sep.join(cdist_object.split(os.sep)[1:])
def object_dir(self, cdist_object):
"""Returns the full path to the object (including .cdist)"""
return os.path.join(self.object_base_dir, cdist_object, DOT_CDIST)
def remote_object_dir(self, cdist_object):
"""Returns the remote full path to the object (including .cdist)"""
return os.path.join(REMOTE_OBJECT_DIR, cdist_object, DOT_CDIST)
def object_parameter_dir(self, cdist_object):
"""Returns the dir to the object parameter"""
return os.path.join(self.object_dir(cdist_object), "parameter")
def remote_object_parameter_dir(self, cdist_object):
"""Returns the remote dir to the object parameter"""
return os.path.join(self.remote_object_dir(cdist_object), "parameter")
def object_code_paths(self, cdist_object):
"""Return paths to code scripts of object"""
return [os.path.join(self.object_dir(cdist_object), "code-local"),
os.path.join(self.object_dir(cdist_object), "code-remote")]
def list_objects(self):
"""Return list of existing objects"""
objects = []
if os.path.isdir(self.object_base_dir):
object_paths = self.list_object_paths(self.object_base_dir)
for path in object_paths:
objects.append(os.path.relpath(path, self.object_base_dir))
return objects
def type_dir(self, type, *args):
"""Return directory the type"""
return os.path.join(self.type_base_dir, type, *args)
def remote_type_explorer_dir(self, type):
"""Return remote directory that holds the explorers of a type"""
return os.path.join(REMOTE_TYPE_DIR, type, "explorer")
def transfer_object_parameter(self, cdist_object):
"""Transfer the object parameter to the remote destination"""
# Create base path before using mkdir -p
self.remote_mkdir(self.remote_object_parameter_dir(cdist_object))
# Synchronise parameter dir afterwards
self.transfer_dir(self.object_parameter_dir(cdist_object),
self.remote_object_parameter_dir(cdist_object))
def transfer_global_explorers(self):
"""Transfer the global explorers"""
self.remote_mkdir(REMOTE_GLOBAL_EXPLORER_DIR)
self.transfer_dir(self.global_explorer_dir, REMOTE_GLOBAL_EXPLORER_DIR)
def transfer_type_explorers(self, type):
"""Transfer explorers of a type, but only once"""
if type in self.type_explorers_transferred:
log.debug("Skipping retransfer for explorers of %s", type)
return
else:
# Do not retransfer
self.type_explorers_transferred[type] = 1
src = self.type_dir(type, "explorer")
remote_base = os.path.join(REMOTE_TYPE_DIR, type)
dst = self.remote_type_explorer_dir(type)
# Only continue, if there is at least the directory
if os.path.isdir(src):
# Ensure that the path exists
self.remote_mkdir(remote_base)
self.transfer_dir(src, dst)
def link_type_to_emulator(self):
"""Link type names to cdist-type-emulator"""
source = os.path.abspath(sys.argv[0])
for type in self.list_types():
destination = os.path.join(self.bin_dir, type)
log.debug("Linking %s to %s", source, destination)
os.symlink(source, destination)
def run_global_explores(self):
"""Run global explorers"""
explorers = self.list_global_explorers()
if(len(explorers) == 0):
exit_error("No explorers found in", self.global_explorer_dir)
self.transfer_global_explorers()
for explorer in explorers:
output = self.global_explorer_output_path(explorer)
output_fd = open(output, mode='w')
cmd = []
cmd.append("__explorer=" + REMOTE_GLOBAL_EXPLORER_DIR)
cmd.append(self.remote_global_explorer_path(explorer))
self.run_or_fail(cmd, stdout=output_fd, remote=True)
output_fd.close()
def run_type_explorer(self, cdist_object):
"""Run type specific explorers for objects"""
# Based on bin/cdist-object-explorer-run
# Transfering explorers for this type
type = self.get_type_from_object(cdist_object)
self.transfer_type_explorers(type)
cmd = []
cmd.append("__explorer=" + REMOTE_GLOBAL_EXPLORER_DIR)
cmd.append("__type_explorer=" + self.remote_type_explorer_dir(type))
cmd.append("__object=" + self.remote_object_dir(cdist_object))
cmd.append("__object_id=" + self.get_object_id_from_object(cdist_object))
cmd.append("__object_fq=" + cdist_object)
# Need to transfer at least the parameters for objects to be useful
self.transfer_object_parameter(cdist_object)
explorers = self.list_type_explorers(type)
for explorer in explorers:
remote_cmd = cmd + [os.path.join(self.remote_type_explorer_dir(type), explorer)]
output = os.path.join(self.type_explorer_output_dir(cdist_object), explorer)
output_fd = open(output, mode='w')
log.debug("%s exploring %s using %s storing to %s",
cdist_object, explorer, remote_cmd, output)
self.run_or_fail(remote_cmd, stdout=output_fd, remote=True)
output_fd.close()
def init_deploy(self):
"""Ensure the base directories are cleaned up"""
log.debug("Creating clean directory structure")
self.remove_remote_dir(REMOTE_BASE_DIR)
self.remote_mkdir(REMOTE_BASE_DIR)
def run_initial_manifest(self):
"""Run the initial manifest"""
env = { "__manifest" : self.manifest_dir }
self.run_manifest(self.initial_manifest, extra_env=env)
def run_type_manifest(self, cdist_object):
"""Run manifest for a specific object"""
type = self.get_type_from_object(cdist_object)
manifest = self.type_dir(type, "manifest")
log.debug("%s: Running %s", cdist_object, manifest)
if os.path.exists(manifest):
env = { "__object" : self.object_dir(cdist_object),
"__object_id": self.get_object_id_from_object(cdist_object),
"__object_fq": cdist_object,
"__type": self.type_dir(type)
}
self.run_manifest(manifest, extra_env=env)
def run_manifest(self, manifest, extra_env=None):
"""Run a manifest"""
log.debug("Running manifest %s, env=%s", manifest, extra_env)
env = os.environ.copy()
env['PATH'] = self.bin_dir + ":" + env['PATH']
# Information required in every manifest
env['__target_host'] = self.target_host
env['__global'] = self.out_dir
# Legacy stuff to make cdist-type-emulator work
env['__cdist_core_dir'] = os.path.join(self.base_dir, "core")
env['__cdist_local_base_dir'] = self.temp_dir
# Submit information to new type emulator
env['__cdist_manifest'] = manifest
env['__cdist_type_base_dir'] = self.type_base_dir
# Other environment stuff
if extra_env:
env.update(extra_env)
self.shell_run_or_debug_fail(manifest, [manifest], env=env)
def object_run(self, cdist_object, mode):
"""Run gencode or code for an object"""
log.debug("Running %s from %s", mode, cdist_object)
file=os.path.join(self.object_dir(cdist_object), "require")
requirements = file_to_list(file)
type = self.get_type_from_object(cdist_object)
for requirement in requirements:
log.debug("Object %s requires %s", cdist_object, requirement)
self.object_run(requirement, mode=mode)
#
# Setup env Variable:
#
env = os.environ.copy()
env['__target_host'] = self.target_host
env['__global'] = self.out_dir
env["__object"] = self.object_dir(cdist_object)
env["__object_id"] = self.get_object_id_from_object(cdist_object)
env["__object_fq"] = cdist_object
env["__type"] = self.type_dir(type)
if mode == "gencode":
paths = [
self.type_dir(type, "gencode-local"),
self.type_dir(type, "gencode-remote")
]
for bin in paths:
if os.path.isfile(bin):
# omit "gen" from gencode and use it for output base
outfile=os.path.join(self.object_dir(cdist_object),
os.path.basename(bin)[3:])
outfile_fd = open(outfile, "w")
# Need to flush to ensure our write is done before stdout write
outfile_fd.write(CODE_HEADER)
outfile_fd.flush()
self.shell_run_or_debug_fail(bin, [bin], env=env, stdout=outfile_fd)
outfile_fd.close()
status = os.stat(outfile)
# Remove output if empty, else make it executable
if status.st_size == len(CODE_HEADER):
os.unlink(outfile)
else:
# Add header and make executable - identically to 0o700
os.chmod(outfile, stat.S_IXUSR | stat.S_IRUSR | stat.S_IWUSR)
# Mark object as changed
open(os.path.join(self.object_dir(cdist_object), "changed"), "w").close()
if mode == "code":
local_dir = self.object_dir(cdist_object)
remote_dir = self.remote_object_dir(cdist_object)
bin = os.path.join(local_dir, "code-local")
if os.path.isfile(bin):
self.run_or_fail([bin], remote=False)
local_remote_code = os.path.join(local_dir, "code-remote")
remote_remote_code = os.path.join(remote_dir, "code-remote")
if os.path.isfile(local_remote_code):
self.transfer_file(local_remote_code, remote_remote_code)
self.run_or_fail([remote_remote_code], remote=True)
def stage_prepare(self):
"""Do everything for a deploy, minus the actual code stage"""
self.init_deploy()
self.run_global_explores()
self.run_initial_manifest()
old_objects = []
objects = self.list_objects()
# Continue process until no new objects are created anymore
while old_objects != objects:
log.debug("Prepare stage")
old_objects = list(objects)
for cdist_object in objects:
if cdist_object in self.objects_prepared:
log.debug("Skipping rerun of object %s", cdist_object)
continue
else:
self.run_type_explorer(cdist_object)
self.run_type_manifest(cdist_object)
self.objects_prepared.append(cdist_object)
objects = self.list_objects()
def stage_run(self):
"""The final (and real) step of deployment"""
log.debug("Actual run objects")
# Now do the final steps over the existing objects
for cdist_object in self.list_objects():
log.debug("Run object: %s", cdist_object)
self.object_run(cdist_object, mode="gencode")
self.object_run(cdist_object, mode="code")
def deploy_to(self):
"""Mimic the old deploy to: Deploy to one host"""
log.info("Deploying to " + self.target_host)
time_start = datetime.datetime.now()
self.stage_prepare()
self.stage_run()
time_end = datetime.datetime.now()
duration = time_end - time_start
log.info("Finished run of %s in %s seconds",
self.target_host,
duration.total_seconds())
def deploy_and_cleanup(self):
"""Do what is most often done: deploy & cleanup"""
self.deploy_to()
self.cleanup()
def banner(args):
"""Guess what :-)"""
print(BANNER)
sys.exit(0)
def config(args):
"""Configure remote system"""
process = {}
time_start = datetime.datetime.now()
for host in args.host:
c = Cdist(host, initial_manifest=args.manifest, home=args.cdist_home, debug=args.debug)
if args.parallel:
log.debug("Creating child process for %s", host)
process[host] = multiprocessing.Process(target=c.deploy_and_cleanup)
process[host].start()
else:
c.deploy_and_cleanup()
if args.parallel:
for p in process.keys():
log.debug("Joining %s", p)
process[p].join()
time_end = datetime.datetime.now()
log.info("Total processing time for %s host(s): %s", len(args.host),
(time_end - time_start).total_seconds())
def install(args):
"""Install remote system"""
process = {}
def emulator():
"""Emulate type commands (i.e. __file and co)"""
type = os.path.basename(sys.argv[0])
type_dir = os.path.join(os.environ['__cdist_type_base_dir'], type)
param_dir = os.path.join(type_dir, "parameter")
global_dir = os.environ['__global']
object_source = os.environ['__cdist_manifest']
parser = argparse.ArgumentParser(add_help=False)
# Setup optional parameters
for parameter in file_to_list(os.path.join(param_dir, "optional")):
argument = "--" + parameter
parser.add_argument(argument, action='store', required=False)
# Setup required parameters
for parameter in file_to_list(os.path.join(param_dir, "required")):
argument = "--" + parameter
parser.add_argument(argument, action='store', required=True)
# Setup positional parameter, if not singleton
if not os.path.isfile(os.path.join(type_dir, "singleton")):
parser.add_argument("object_id", nargs=1)
# And finally verify parameter
args = parser.parse_args(sys.argv[1:])
# Setup object_id
if os.path.isfile(os.path.join(type_dir, "singleton")):
object_id = "singleton"
else:
object_id = args.object_id[0]
del args.object_id
# FIXME: / hardcoded - better portable solution available?
if object_id[0] == '/':
object_id = object_id[1:]
# FIXME: verify object id
log.debug(args)
object_dir = os.path.join(global_dir, "object", type,
object_id, DOT_CDIST)
param_out_dir = os.path.join(object_dir, "parameter")
object_source_file = os.path.join(object_dir, "source")
if os.path.exists(param_out_dir):
object_exists = True
old_object_source_fd = open(object_source_file, "r")
old_object_source = old_object_source_fd.readlines()
old_object_source_fd.close()
else:
object_exists = False
try:
os.makedirs(param_out_dir, exist_ok=True)
except OSError as error:
exit_error(param_out_dir + ": " + error.args[1])
# Record parameter
params = vars(args)
for param in params:
value = getattr(args, param)
if value:
file = os.path.join(param_out_dir, param)
log.debug(file + "<-" + param + " = " + value)
# Already exists, verify all parameter are the same
if object_exists:
if not os.path.isfile(file):
print("New parameter + " + param + "specified, aborting")
print("Source = " + old_object_source + "new =" + object_source)
sys.exit(1)
else:
param_fd = open(file, "r")
param_old = param_fd.readlines()
param_fd.close()
if(param_old != param):
print("Parameter " + param + " differs: " + " ".join(param_old) + " vs. " + param)
print("Sources: " + " ".join(old_object_source) + " and " + object_source)
sys.exit(1)
else:
param_fd = open(file, "w")
param_fd.writelines(value)
param_fd.close()
# Record requirements
if "__require" in os.environ:
requirements = os.environ['__require']
print(object_id + ":Writing requirements: " + requirements)
require_fd = open(os.path.join(object_dir, "require"), "a")
require_fd.writelines(requirements.split(" "))
require_fd.close()
# Record / Append source
source_fd = open(os.path.join(object_dir, "source"), "a")
source_fd.writelines(object_source)
source_fd.close()
# sys.exit(1)
print("Finished " + type + "/" + object_id + repr(params))
def commandline():
"""Parse command line"""
# Construct parser others can reuse
parser = {}
# Options _all_ parsers have in common
parser['most'] = argparse.ArgumentParser(add_help=False)
parser['most'].add_argument('-d', '--debug',
help='Set log level to debug', action='store_true')
# Main subcommand parser
parser['main'] = argparse.ArgumentParser(description='cdist ' + VERSION)
parser['main'].add_argument('-V', '--version',
help='Show version', action='version',
version='%(prog)s ' + VERSION)
parser['sub'] = parser['main'].add_subparsers(title="Commands")
# Banner
parser['banner'] = parser['sub'].add_parser('banner',
add_help=False)
parser['banner'].set_defaults(func=banner)
# Config and install (common stuff)
parser['configinstall'] = argparse.ArgumentParser(add_help=False)
parser['configinstall'].add_argument('host', nargs='+',
help='one or more hosts to operate on')
parser['configinstall'].add_argument('-c', '--cdist-home',
help='Change cdist home (default: .. from bin directory)',
action='store')
parser['configinstall'].add_argument('-i', '--initial-manifest',
help='Path to a cdist manifest',
dest='manifest', required=False)
parser['configinstall'].add_argument('-p', '--parallel',
help='Operate on multiple hosts in parallel',
action='store_true', dest='parallel')
parser['configinstall'].add_argument('-s', '--sequential',
help='Operate on multiple hosts sequentially (default)',
action='store_false', dest='parallel')
# Config
parser['config'] = parser['sub'].add_parser('config',
parents=[parser['most'], parser['configinstall']])
parser['config'].set_defaults(func=config)
# Install
parser['install'] = parser['sub'].add_parser('install',
parents=[parser['most'], parser['configinstall']])
parser['install'].set_defaults(func=install)
for p in parser:
parser[p].epilog = "Get cdist at http://www.nico.schottelius.org/software/cdist/"
args = parser['main'].parse_args(sys.argv[1:])
# Most subcommands have --debug, so handle it here
if 'debug' in args:
if args.debug:
logging.root.setLevel(logging.DEBUG)
log.debug(args)
args.func(args)
if __name__ == "__main__":
try:
if re.match(TYPE_PREFIX, os.path.basename(sys.argv[0])):
emulator()
else:
commandline()
except KeyboardInterrupt:
sys.exit(0)