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Diffstat (limited to 'cloudinit/DataSourceMaaS.py')
| -rw-r--r-- | cloudinit/DataSourceMaaS.py | 308 |
1 files changed, 308 insertions, 0 deletions
diff --git a/cloudinit/DataSourceMaaS.py b/cloudinit/DataSourceMaaS.py new file mode 100644 index 00000000..2bc1f71f --- /dev/null +++ b/cloudinit/DataSourceMaaS.py @@ -0,0 +1,308 @@ +# vi: ts=4 expandtab +# +# Copyright (C) 2009-2010 Canonical Ltd. +# Copyright (C) 2012 Hewlett-Packard Development Company, L.P. +# +# Author: Scott Moser <scott.moser@canonical.com> +# Author: Juerg Hafliger <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 cloudinit.DataSource as DataSource + +from cloudinit import seeddir as base_seeddir +from cloudinit import log +import cloudinit.util as util +import errno +import oauth.oauth as oauth +import os.path +import socket +import urllib2 +import time + + +class DataSourceMaaS(DataSource.DataSource): + """ + DataSourceMaaS reads instance information from MaaS. + Given a config metadata_url, and oauth tokens, it expects to find + files under the root named: + instance-id + user-data + hostname + """ + seeddir = base_seeddir + '/maas' + baseurl = None + + def __str__(self): + return("DataSourceMaaS[%s]" % self.baseurl) + + def get_data(self): + mcfg = self.ds_cfg + + try: + (userdata, metadata) = read_maas_seed_dir(self.seeddir) + self.userdata_raw = userdata + self.metadata = metadata + self.baseurl = self.seeddir + return True + except MaasSeedDirNone: + pass + except MaasSeedDirMalformed as exc: + log.warn("%s was malformed: %s\n" % (self.seeddir, exc)) + raise + + try: + # if there is no metadata_url, then we're not configured + url = mcfg.get('metadata_url', None) + if url == None: + return False + + if not self.wait_for_metadata_service(url): + return False + + self.baseurl = url + + (userdata, metadata) = read_maas_seed_url(self.baseurl, + self.md_headers) + return True + except Exception: + util.logexc(log) + return False + + def md_headers(self, url): + mcfg = self.ds_cfg + + # if we are missing token_key, token_secret or consumer_key + # then just do non-authed requests + for required in ('token_key', 'token_secret', 'consumer_key'): + if required not in mcfg: + return({}) + + consumer_secret = mcfg.get('consumer_secret', "") + + return(oauth_headers(url=url, consumer_key=mcfg['consumer_key'], + token_key=mcfg['token_key'], token_secret=mcfg['token_secret'], + consumer_secret=consumer_secret)) + + def wait_for_metadata_service(self, url): + mcfg = self.ds_cfg + + max_wait = 120 + try: + max_wait = int(mcfg.get("max_wait", max_wait)) + except Exception: + util.logexc(log) + log.warn("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) + log.warn("Failed to get timeout, using %s" % timeout) + + starttime = time.time() + check_url = "%s/instance-id" % url + url = wait_for_metadata_service(urls=[check_url], max_wait=max_wait, + timeout=timeout, status_cb=log.warn, + headers_cb=self.md_headers) + + if url: + log.debug("Using metadata source: '%s'" % url) + else: + log.critical("giving up on md after %i seconds\n" % + int(time.time() - starttime)) + + return (bool(url)) + + +def wait_for_metadata_service(urls, max_wait=None, timeout=None, + status_cb=None, headers_cb=None): + """ + urls: a list of urls to try + max_wait: roughly the maximum time to wait before giving up + The max time is *actually* len(urls)*timeout as each url will + be tried once and given the timeout provided. + timeout: the timeout provided to urllib2.urlopen + status_cb: call method with string message when a url is not available + + the idea of this routine is to wait for the EC2 metdata service to + come up. On both Eucalyptus and EC2 we have seen the case where + the instance hit the MD before the MD service was up. EC2 seems + to have permenantely fixed this, though. + + In openstack, the metadata service might be painfully slow, and + unable to avoid hitting a timeout of even up to 10 seconds or more + (LP: #894279) for a simple GET. + + Offset those needs with the need to not hang forever (and block boot) + on a system where cloud-init is configured to look for EC2 Metadata + service but is not going to find one. It is possible that the instance + data host (169.254.169.254) may be firewalled off Entirely for a sytem, + meaning that the connection will block forever unless a timeout is set. + """ + starttime = time.time() + + sleeptime = 1 + + def nullstatus_cb(msg): + return + + if status_cb == None: + status_cb = nullstatus_cb + + def timeup(max_wait, starttime): + return((max_wait <= 0 or max_wait == None) or + (time.time() - starttime > max_wait)) + + loop_n = 0 + while True: + sleeptime = int(loop_n / 5) + 1 + for url in urls: + now = time.time() + if loop_n != 0: + if timeup(max_wait, starttime): + break + if timeout and (now + timeout > (starttime + max_wait)): + # shorten timeout to not run way over max_time + timeout = int((starttime + max_wait) - now) + + reason = "" + try: + if headers_cb != None: + headers = headers_cb(url) + else: + headers = {} + + req = urllib2.Request(url, data=None, headers=headers) + resp = urllib2.urlopen(req, timeout=timeout) + if resp.read() != "": + return url + 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 + except Exception as e: + reason = "unexpected error [%s]" % e + + if log: + status_cb("'%s' failed [%s/%ss]: %s" % + (url, int(time.time() - starttime), max_wait, + reason)) + + if timeup(max_wait, starttime): + break + + loop_n = loop_n + 1 + time.sleep(sleeptime) + + return False + + +def read_maas_seed_dir(seed_d): + """ + Return user-data and metadata for a maas seed dir in seed_d. + Expected format of seed_d are the following files: + * instance-id + * hostname + * user-data + """ + md_required = set(('hostname', 'instance-id')) + files = md_required.union(set(('userdata',))) + userdata = None + md = {} + + if not os.path.isdir(seed_d): + raise MaasSeedDirNone("%s: not a directory") + + for fname in files: + try: + with open(os.path.join(seed_d, fname)) as fp: + if fname == 'userdata': + userdata = fp.read() + else: + md[fname] = fp.read() + fp.close() + except IOError as e: + if e.errno != errno.ENOENT: + raise + + if userdata == None and len(md) == 0: + raise MaasSeedDirNone("%s: no data files found" % seed_d) + + if userdata == None: + raise MaasSeedDirMalformed("%s: missing userdata" % seed_d) + + missing = md_required - set(md.keys()) + if len(missing): + raise MaasSeedDirMalformed("%s: missing files %s" % + (seed_d, str(missing))) + + return(userdata, md) + + +def read_maas_seed_url(seed_url, header_cb=None): + """ + Read the maas datasource at seed_url. + header_cb is a method that should return a headers dictionary that will + be given to urllib2.Request() + + Expected format of seed_url is are the following files: + * <seed_url>/instance-id + * <seed_url>/hostname + * <seed_url>/user-data + """ + userdata = "" + metadata = {'instance-id': 'i-maas-url', 'hostname': 'maas-url-hostname'} + + return(userdata, metadata) + + +def oauth_headers(url, consumer_key, token_key, token_secret, consumer_secret): + consumer = oauth.OAuthConsumer(consumer_key, consumer_secret) + token = oauth.OAuthToken(token_key, token_secret) + params = { + 'oauth_version': "1.0", + 'oauth_nonce': oauth.generate_nonce(), + 'oauth_timestamp': int(time.time()), + 'oauth_token': token.key, + 'oauth_consumer_key': consumer.key, + } + req = oauth.OAuthRequest(http_url=url, parameters=params) + req.sign_request(oauth.OAuthSignatureMethod_PLAINTEXT(), + consumer, token) + return(req.to_header()) + + +class MaasSeedDirNone(Exception): + pass + + +class MaasSeedDirMalformed(Exception): + pass + + +datasources = [ + (DataSourceMaaS, (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)) |