cloud-init/cloudinit/sources/DataSourceCloudStack.py
2013-06-19 08:44:00 +02:00

201 lines
6.8 KiB
Python

# vi: ts=4 expandtab
#
# Copyright (C) 2012 Canonical Ltd.
# Copyright (C) 2012 Cosmin Luta
# Copyright (C) 2012 Yahoo! Inc.
# Copyright (C) 2012 Gerard Dethier
# Copyright (C) 2013 Hewlett-Packard Development Company, L.P.
#
# Author: Cosmin Luta <q4break@gmail.com>
# Author: Scott Moser <scott.moser@canonical.com>
# Author: Joshua Harlow <harlowja@yahoo-inc.com>
# Author: Gerard Dethier <g.dethier@gmail.com>
# Author: Juerg Haefliger <juerg.haefliger@hp.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 os
import time
from cloudinit import ec2_utils as ec2
from cloudinit import log as logging
from cloudinit import sources
from cloudinit import url_helper as uhelp
from cloudinit import util
from socket import inet_ntoa
from struct import pack
LOG = logging.getLogger(__name__)
class DataSourceCloudStack(sources.DataSource):
def __init__(self, sys_cfg, distro, paths):
sources.DataSource.__init__(self, sys_cfg, distro, paths)
self.seed_dir = os.path.join(paths.seed_dir, 'cs')
# Cloudstack has its metadata/userdata URLs located at
# http://<virtual-router-ip>/latest/
self.api_ver = 'latest'
vr_addr = get_vr_address()
if not vr_addr:
raise RuntimeError("No virtual router found!")
self.metadata_address = "http://%s/" % (vr_addr)
def _get_url_settings(self):
mcfg = self.ds_cfg
if not mcfg:
mcfg = {}
max_wait = 120
try:
max_wait = int(mcfg.get("max_wait", max_wait))
except Exception:
util.logexc(LOG, "Failed to get max wait. using %s", max_wait)
if max_wait == 0:
return False
timeout = 50
try:
timeout = int(mcfg.get("timeout", timeout))
except Exception:
util.logexc(LOG, "Failed to get timeout, using %s", timeout)
return (max_wait, timeout)
def wait_for_metadata_service(self):
mcfg = self.ds_cfg
if not mcfg:
mcfg = {}
(max_wait, timeout) = self._get_url_settings()
urls = [self.metadata_address + "/latest/meta-data/instance-id"]
start_time = time.time()
url = uhelp.wait_for_url(urls=urls, max_wait=max_wait,
timeout=timeout, status_cb=LOG.warn)
if url:
LOG.debug("Using metadata source: '%s'", url)
else:
LOG.critical(("Giving up on waiting for the metadata from %s"
" after %s seconds"),
urls, int(time.time() - start_time))
return bool(url)
def get_data(self):
seed_ret = {}
if util.read_optional_seed(seed_ret, base=(self.seed_dir + "/")):
self.userdata_raw = seed_ret['user-data']
self.metadata = seed_ret['meta-data']
LOG.debug("Using seeded cloudstack data from: %s", self.seed_dir)
return True
try:
if not self.wait_for_metadata_service():
return False
start_time = time.time()
self.userdata_raw = ec2.get_instance_userdata(self.api_ver,
self.metadata_address)
self.metadata = ec2.get_instance_metadata(self.api_ver,
self.metadata_address)
LOG.debug("Crawl of metadata service took %s seconds",
int(time.time() - start_time))
return True
except Exception:
util.logexc(LOG, 'Failed fetching from metadata service %s',
self.metadata_address)
return False
def get_instance_id(self):
return self.metadata['instance-id']
@property
def availability_zone(self):
return self.metadata['availability-zone']
def get_default_gateway():
# Returns the default gateway ip address in the dotted format.
lines = util.load_file("/proc/net/route").splitlines()
for line in lines:
items = line.split("\t")
if items[1] == "00000000":
# Found the default route, get the gateway
gw = inet_ntoa(pack("<L", int(items[2], 16)))
LOG.debug("Found default route, gateway is %s", gw)
return gw
return None
def get_dhclient_d():
# find lease files directory
supported_dirs = ["/var/lib/dhclient", "/var/lib/dhcp"]
for d in supported_dirs:
if os.path.exists(d):
LOG.debug("Using %s lease directory", d)
return d
return None
def get_latest_lease():
# find latest lease file
lease_d = get_dhclient_d()
if not lease_d:
return None
lease_files = os.listdir(lease_d)
latest_mtime = -1
latest_file = None
for file_name in lease_files:
if file_name.endswith(".lease") or file_name.endswith(".leases"):
abs_path = os.path.join(lease_d, file_name)
mtime = os.path.getmtime(abs_path)
if mtime > latest_mtime:
latest_mtime = mtime
latest_file = abs_path
return latest_file
def get_vr_address():
# Get the address of the virtual router via dhcp leases
# see http://bit.ly/T76eKC for documentation on the virtual router.
# If no virtual router is detected, fallback on default gateway.
lease_file = get_latest_lease()
if not lease_file:
LOG.debug("No lease file found, using default gateway")
return get_default_gateway()
latest_address = None
with open(lease_file, "r") as fd:
for line in fd:
if "dhcp-server-identifier" in line:
words = line.strip(" ;\r\n").split(" ")
if len(words) > 2:
dhcp = words[2]
LOG.debug("Found DHCP identifier %s", dhcp)
latest_address = dhcp
if not latest_address:
# No virtual router found, fallback on default gateway
LOG.debug("No DHCP found, using default gateway")
return get_default_gateway()
return latest_address
# Used to match classes to dependencies
datasources = [
(DataSourceCloudStack, (sources.DEP_FILESYSTEM, sources.DEP_NETWORK)),
]
# Return a list of data sources that match this set of dependencies
def get_datasource_list(depends):
return sources.list_from_depends(depends, datasources)