cloud-init/cloudinit/config/cc_write_files.py

103 lines
3.5 KiB
Python

# vi: ts=4 expandtab
#
# Copyright (C) 2012 Yahoo! Inc.
#
# Author: Joshua Harlow <harlowja@yahoo-inc.com>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 3, as
# published by the Free Software Foundation.
#
# This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
import base64
import os
from cloudinit.settings import PER_INSTANCE
from cloudinit import util
frequency = PER_INSTANCE
DEFAULT_OWNER = "root:root"
DEFAULT_PERMS = 0644
UNKNOWN_ENC = 'text/plain'
def handle(name, cfg, _cloud, log, _args):
files = cfg.get('write_files')
if not files:
log.debug(("Skipping module named %s,"
" no/empty 'write_files' key in configuration"), name)
return
write_files(name, files, log)
def canonicalize_extraction(encoding_type, log):
if not encoding_type:
encoding_type = ''
encoding_type = encoding_type.lower().strip()
if encoding_type in ['gz', 'gzip']:
return ['application/x-gzip']
if encoding_type in ['gz+base64', 'gzip+base64', 'gz+b64', 'gzip+b64']:
return ['application/base64', 'application/x-gzip']
# Yaml already encodes binary data as base64 if it is given to the
# yaml file as binary, so those will be automatically decoded for you.
# But the above b64 is just for people that are more 'comfortable'
# specifing it manually (which might be a possiblity)
if encoding_type in ['b64', 'base64']:
return ['application/base64']
if encoding_type:
log.warn("Unknown encoding type %s, assuming %s",
encoding_type, UNKNOWN_ENC)
return [UNKNOWN_ENC]
def write_files(name, files, log):
if not files:
return
for (i, f_info) in enumerate(files):
path = f_info.get('path')
if not path:
log.warn("No path provided to write for entry %s in module %s",
i + 1, name)
continue
path = os.path.abspath(path)
extractions = canonicalize_extraction(f_info.get('encoding'), log)
contents = extract_contents(f_info.get('content', ''), extractions)
(u, g) = util.extract_usergroup(f_info.get('owner', DEFAULT_OWNER))
perms = decode_perms(f_info.get('permissions'), DEFAULT_PERMS, log)
util.write_file(path, contents, mode=perms)
util.chownbyname(path, u, g)
def decode_perms(perm, default, log):
try:
if isinstance(perm, (int, long, float)):
# Just 'downcast' it (if a float)
return int(perm)
else:
# Force to string and try octal conversion
return int(str(perm), 8)
except (TypeError, ValueError):
log.warn("Undecodable permissions %s, assuming %s", perm, default)
return default
def extract_contents(contents, extraction_types):
result = str(contents)
for t in extraction_types:
if t == 'application/x-gzip':
result = util.decomp_gzip(result, quiet=False)
elif t == 'application/base64':
result = base64.b64decode(result)
elif t == UNKNOWN_ENC:
pass
return result