cloud-init/cloudinit/DataSourceEc2.py
2011-12-16 11:43:35 -05:00

240 lines
8.1 KiB
Python

# vi: ts=4 expandtab
#
# Copyright (C) 2009-2010 Canonical Ltd.
#
# Author: Scott Moser <scott.moser@canonical.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 DataSource
from cloudinit import seeddir, log
import cloudinit.util as util
import socket
import urllib2
import time
import sys
import boto.utils as boto_utils
import os.path
import errno
import urlparse
class DataSourceEc2(DataSource.DataSource):
api_ver = '2009-04-04'
seeddir = seeddir + '/ec2'
metadata_address = "http://169.254.169.254"
def __str__(self):
return("DataSourceEc2")
def get_data(self):
seedret={ }
if util.read_optional_seed(seedret,base=self.seeddir+ "/"):
self.userdata_raw = seedret['user-data']
self.metadata = seedret['meta-data']
log.debug("using seeded ec2 data in %s" % self.seeddir)
return True
try:
if not self.wait_for_metadata_service():
return False
self.userdata_raw = boto_utils.get_instance_userdata(self.api_ver, None, self.metadata_address)
self.metadata = boto_utils.get_instance_metadata(self.api_ver, self.metadata_address)
return True
except Exception as e:
print e
return False
def get_instance_id(self):
return(self.metadata['instance-id'])
def get_availability_zone(self):
return(self.metadata['placement']['availability-zone'])
def get_local_mirror(self):
return(self.get_mirror_from_availability_zone())
def get_mirror_from_availability_zone(self, availability_zone = None):
# availability is like 'us-west-1b' or 'eu-west-1a'
if availability_zone == None:
availability_zone = self.get_availability_zone()
fallback = None
if self.is_vpc():
return fallback
try:
host="%s.ec2.archive.ubuntu.com" % availability_zone[:-1]
socket.getaddrinfo(host, None, 0, socket.SOCK_STREAM)
return 'http://%s/ubuntu/' % host
except:
return fallback
def wait_for_metadata_service(self, sleeps = None):
mcfg = self.ds_cfg
if sleeps is None:
sleeps = 30
try:
sleeps = int(mcfg.get("retries",sleeps))
except Exception as e:
util.logexc(log)
log.warn("Failed to get number of sleeps, using %s" % sleeps)
if sleeps == 0: return False
timeout=3
try:
timeout = int(mcfg.get("timeout",timeout))
except Exception as e:
util.logexc(log)
log.warn("Failed to get timeout, using %s" % timeout)
sleeptime = 1
def_mdurls = ["http://169.254.169.254", "http://instance-data:8773"]
try:
mdurls = mcfg.get("metadata_urls", def_mdurls)
except Exception as e:
mdurls = def_mdurls
util.logexc(log)
log.warn("Failed to get metadata URLs, using defaults")
starttime = time.time()
# Remove addresses from the list that wont resolve.
filtered = [x for x in mdurls if try_to_resolve_metadata(x)]
if set(filtered) != set(mdurls):
log.debug("removed the following from metadata urls: %s" %
list((set(mdurls) - set(filtered))))
if len(filtered):
mdurls = filtered
else:
log.warn("Empty metadata url list! using default list")
mdurls = def_mdurls
log.debug("Searching the following metadata urls: %s" % mdurls)
for x in range(sleeps):
for url in mdurls:
iurl="%s/%s/meta-data/instance-id" % (url, self.api_ver)
# given 100 sleeps, this ends up total sleep time of 1050 sec
sleeptime=int(x/5)+1
reason = ""
try:
req = urllib2.Request(iurl)
resp = urllib2.urlopen(req, timeout=timeout)
if resp.read() != "":
self.metadata_address = url
log.debug("Using metadata source: '%s'" % url)
return True
reason = "empty data [%s]" % resp.getcode()
except urllib2.HTTPError as e:
reason = "http error [%s]" % e.code
except urllib2.URLError as e:
reason = "url error [%s]" % e.reason
except socket.timeout as e:
reason = "socket timeout [%s]" % e
#not needed? Addresses being checked are displayed above
#if x == 0:
# log.warn("waiting for metadata service at %s" % url)
log.warn("'%s' failed: %s" % (url, reason))
time.sleep(sleeptime)
log.critical("giving up on md after %i seconds\n" %
int(time.time()-starttime))
return False
def device_name_to_device(self, name):
# consult metadata service, that has
# ephemeral0: sdb
# and return 'sdb' for input 'ephemeral0'
if not self.metadata.has_key('block-device-mapping'):
return(None)
found = None
for entname, device in self.metadata['block-device-mapping'].items():
if entname == name:
found = device
break
# LP: #513842 mapping in Euca has 'ephemeral' not 'ephemeral0'
if entname == "ephemeral" and name == "ephemeral0":
found = device
if found == None:
log.debug("unable to convert %s to a device" % name)
return None
# LP: #611137
# the metadata service may believe that devices are named 'sda'
# when the kernel named them 'vda' or 'xvda'
# we want to return the correct value for what will actually
# exist in this instance
mappings = { "sd": ("vd", "xvd") }
ofound = found
short = os.path.basename(found)
if not found.startswith("/"):
found="/dev/%s" % found
if os.path.exists(found):
return(found)
for nfrom, tlist in mappings.items():
if not short.startswith(nfrom): continue
for nto in tlist:
cand = "/dev/%s%s" % (nto, short[len(nfrom):])
if os.path.exists(cand):
log.debug("remapped device name %s => %s" % (found,cand))
return(cand)
# on t1.micro, ephemeral0 will appear in block-device-mapping from
# metadata, but it will not exist on disk (and never will)
# at this pint, we've verified that the path did not exist
# in the special case of 'ephemeral0' return None to avoid bogus
# fstab entry (LP: #744019)
if name == "ephemeral0":
return None
return ofound
def is_vpc(self):
# per comment in LP: #615545
ph="public-hostname"; p4="public-ipv4"
if ((ph not in self.metadata or self.metadata[ph] == "") and
(p4 not in self.metadata or self.metadata[p4] == "")):
return True
return False
def try_to_resolve_metadata(url):
try:
addr = urlparse.urlsplit(url).netloc.split(":")[0]
socket.getaddrinfo(addr, None)
return True
except Exception as e:
return False
datasources = [
( DataSourceEc2, ( DataSource.DEP_FILESYSTEM , DataSource.DEP_NETWORK ) ),
]
# return a list of data sources that match this set of dependencies
def get_datasource_list(depends):
return(DataSource.list_from_depends(depends, datasources))