diff options
Diffstat (limited to 'cloudinit/ec2_utils.py')
| -rw-r--r-- | cloudinit/ec2_utils.py | 205 |
1 files changed, 160 insertions, 45 deletions
diff --git a/cloudinit/ec2_utils.py b/cloudinit/ec2_utils.py index fcd511c5..c86623bc 100644 --- a/cloudinit/ec2_utils.py +++ b/cloudinit/ec2_utils.py @@ -16,48 +16,163 @@ # 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 boto.utils as boto_utils - -# Versions of boto >= 2.6.0 (and possibly 2.5.2) -# try to lazily load the metadata backing, which -# doesn't work so well in cloud-init especially -# since the metadata is serialized and actions are -# performed where the metadata server may be blocked -# (thus the datasource will start failing) resulting -# in url exceptions when fields that do exist (or -# would have existed) do not exist due to the blocking -# that occurred. - -# TODO(harlowja): https://github.com/boto/boto/issues/1401 -# When boto finally moves to using requests, we should be able -# to provide it ssl details, it does not yet, so we can't provide them... - - -def _unlazy_dict(mp): - if not isinstance(mp, (dict)): - return mp - # Walk over the keys/values which - # forces boto to unlazy itself and - # has no effect on dictionaries that - # already have there items. - for (_k, v) in mp.items(): - _unlazy_dict(v) - return mp - - -def get_instance_userdata(api_version, metadata_address): - # Note: boto.utils.get_instance_metadata returns '' for empty string - # so the change from non-true to '' is not specifically necessary, but - # this way cloud-init will get consistent behavior even if boto changed - # in the future to return a None on "no user-data provided". - ud = boto_utils.get_instance_userdata(api_version, None, metadata_address) - if not ud: - ud = '' - return ud - - -def get_instance_metadata(api_version, metadata_address): - metadata = boto_utils.get_instance_metadata(api_version, metadata_address) - if not isinstance(metadata, (dict)): - metadata = {} - return _unlazy_dict(metadata) +from urlparse import (urlparse, urlunparse) + +import functools +import json +import urllib + +from cloudinit import log as logging +from cloudinit import util + +LOG = logging.getLogger(__name__) + + +def maybe_json_object(text): + if not text: + return False + text = text.strip() + if text.startswith("{") and text.endswith("}"): + return True + return False + + +def combine_url(base, add_on): + base_parsed = list(urlparse(base)) + path = base_parsed[2] + if path and not path.endswith("/"): + path += "/" + path += urllib.quote(str(add_on), safe="/:") + base_parsed[2] = path + return urlunparse(base_parsed) + + +# See: http://bit.ly/TyoUQs +# +# Since boto metadata reader uses the old urllib which does not +# support ssl, we need to ahead and create our own reader which +# works the same as the boto one (for now). +class MetadataMaterializer(object): + def __init__(self, blob, base_url, caller): + self._blob = blob + self._md = None + self._base_url = base_url + self._caller = caller + + def _parse(self, blob): + leaves = {} + children = [] + if not blob: + return (leaves, children) + + def has_children(item): + if item.endswith("/"): + return True + else: + return False + + def get_name(item): + if item.endswith("/"): + return item.rstrip("/") + return item + + for field in blob.splitlines(): + field = field.strip() + field_name = get_name(field) + if not field or not field_name: + continue + if has_children(field): + if field_name not in children: + children.append(field_name) + else: + contents = field.split("=", 1) + resource = field_name + if len(contents) > 1: + # What a PITA... + (ident, sub_contents) = contents + ident = util.safe_int(ident) + if ident is not None: + resource = "%s/openssh-key" % (ident) + field_name = sub_contents + leaves[field_name] = resource + return (leaves, children) + + def materialize(self): + if self._md is not None: + return self._md + self._md = self._materialize(self._blob, self._base_url) + return self._md + + def _decode_leaf_blob(self, field, blob): + if not blob: + return blob + if maybe_json_object(blob): + try: + # Assume it's json, unless it fails parsing... + return json.loads(blob) + except (ValueError, TypeError) as e: + LOG.warn("Field %s looked like a json object, but it was" + " not: %s", field, e) + if blob.find("\n") != -1: + return blob.splitlines() + return blob + + def _materialize(self, blob, base_url): + (leaves, children) = self._parse(blob) + child_contents = {} + for c in children: + child_url = combine_url(base_url, c) + if not child_url.endswith("/"): + child_url += "/" + child_blob = str(self._caller(child_url)) + child_contents[c] = self._materialize(child_blob, child_url) + leaf_contents = {} + for (field, resource) in leaves.items(): + leaf_url = combine_url(base_url, resource) + leaf_blob = str(self._caller(leaf_url)) + leaf_contents[field] = self._decode_leaf_blob(field, leaf_blob) + joined = {} + joined.update(child_contents) + for field in leaf_contents.keys(): + if field in joined: + LOG.warn("Duplicate key found in results from %s", base_url) + else: + joined[field] = leaf_contents[field] + return joined + + +def get_instance_userdata(api_version='latest', + metadata_address='http://169.254.169.254', + ssl_details=None, timeout=5, retries=5): + ud_url = combine_url(metadata_address, api_version) + ud_url = combine_url(ud_url, 'user-data') + try: + response = util.read_file_or_url(ud_url, + ssl_details=ssl_details, + timeout=timeout, + retries=retries) + return str(response) + except Exception: + util.logexc(LOG, "Failed fetching userdata from url %s", ud_url) + return '' + + +def get_instance_metadata(api_version='latest', + metadata_address='http://169.254.169.254', + ssl_details=None, timeout=5, retries=5): + md_url = combine_url(metadata_address, api_version) + md_url = combine_url(md_url, 'meta-data') + caller = functools.partial(util.read_file_or_url, + ssl_details=ssl_details, timeout=timeout, + retries=retries) + + try: + response = caller(md_url) + materializer = MetadataMaterializer(str(response), md_url, caller) + md = materializer.materialize() + if not isinstance(md, (dict)): + md = {} + return md + except Exception: + util.logexc(LOG, "Failed fetching metadata from url %s", md_url) + return {} |