# vi: ts=4 expandtab # # Copyright (C) 2012 Canonical Ltd. # Copyright (C) 2012 Yahoo! Inc. # # Author: Scott Moser # Author: Joshua Harlow # # 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 . import errno import oauth.oauth as oauth import os import time import urllib2 from cloudinit import log as logging from cloudinit import sources from cloudinit import url_helper as uhelp from cloudinit import util LOG = logging.getLogger(__name__) MD_VERSION = "2012-03-01" class DataSourceMAAS(sources.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 """ def __init__(self, sys_cfg, distro, paths): sources.DataSource.__init__(self, sys_cfg, distro, paths) self.base_url = None self.seed_dir = os.path.join(paths.seed_dir, 'maas') def __str__(self): return "%s [%s]" % (util.obj_name(self), self.base_url) def get_data(self): mcfg = self.ds_cfg try: (userdata, metadata) = read_maas_seed_dir(self.seed_dir) self.userdata_raw = userdata self.metadata = metadata self.base_url = self.seed_dir return True except MAASSeedDirNone: pass except MAASSeedDirMalformed as exc: LOG.warn("%s was malformed: %s" % (self.seed_dir, exc)) raise # If there is no metadata_url, then we're not configured url = mcfg.get('metadata_url', None) if not url: return False try: if not self.wait_for_metadata_service(url): return False self.base_url = url (userdata, metadata) = read_maas_seed_url(self.base_url, self.md_headers) self.userdata_raw = userdata self.metadata = metadata return True except Exception: util.logexc(LOG, "Failed fetching metadata from url %s", url) 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, "Failed to get max wait. using %s", max_wait) if max_wait == 0: return False timeout = 50 try: if timeout in mcfg: timeout = int(mcfg.get("timeout", timeout)) except Exception: LOG.warn("Failed to get timeout, using %s" % timeout) starttime = time.time() check_url = "%s/%s/meta-data/instance-id" % (url, MD_VERSION) urls = [check_url] url = uhelp.wait_for_url(urls=urls, max_wait=max_wait, timeout=timeout, status_cb=LOG.warn, headers_cb=self.md_headers) if url: LOG.info("Using metadata source: '%s'", url) else: LOG.critical("Giving up on md from %s after %i seconds", urls, int(time.time() - starttime)) return bool(url) 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 * local-hostname * user-data """ if not os.path.isdir(seed_d): raise MAASSeedDirNone("%s: not a directory") files = ('local-hostname', 'instance-id', 'user-data', 'public-keys') md = {} for fname in files: try: md[fname] = util.load_file(os.path.join(seed_d, fname)) except IOError as e: if e.errno != errno.ENOENT: raise return check_seed_contents(md, seed_d) def read_maas_seed_url(seed_url, header_cb=None, timeout=None, version=MD_VERSION): """ 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: * //meta-data/instance-id * //meta-data/local-hostname * //user-data """ base_url = "%s/%s" % (seed_url, version) files = { 'local-hostname': "%s/%s" % (base_url, 'meta-data/local-hostname'), 'instance-id': "%s/%s" % (base_url, 'meta-data/instance-id'), 'public-keys': "%s/%s" % (base_url, 'meta-data/public-keys'), 'user-data': "%s/%s" % (base_url, 'user-data'), } md = {} for (name, url) in files: if header_cb: headers = header_cb(url) else: headers = {} try: (resp, sc) = uhelp.readurl(url, headers=headers, timeout=timeout) if uhelp.ok_http_code(sc): md[name] = resp except urllib2.HTTPError as e: if e.code != 404: raise return check_seed_contents(md, seed_url) def check_seed_contents(content, seed): """Validate if content is Is the content a dict that is valid as a return for a datasource. Either return a (userdata, metadata) tuple or Raise MAASSeedDirMalformed or MAASSeedDirNone """ md_required = ('instance-id', 'local-hostname') if len(content) == 0: raise MAASSeedDirNone("%s: no data files found" % seed) found = content.keys() missing = [k for k in md_required if k not in found] if len(missing): raise MAASSeedDirMalformed("%s: missing files %s" % (seed, missing)) userdata = content.get('user-data', "") md = {} for (key, val) in content.iteritems(): if key == 'user-data': continue md[key] = val return (userdata, md) 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 # Used to match classes to dependencies datasources = [ (DataSourceMAAS, (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)