diff options
Diffstat (limited to 'cloudinit/handlers/cloud_config.py')
| -rw-r--r-- | cloudinit/handlers/cloud_config.py | 92 |
1 files changed, 77 insertions, 15 deletions
diff --git a/cloudinit/handlers/cloud_config.py b/cloudinit/handlers/cloud_config.py index f6d95244..d30d6338 100644 --- a/cloudinit/handlers/cloud_config.py +++ b/cloudinit/handlers/cloud_config.py @@ -22,41 +22,103 @@ from cloudinit import handlers from cloudinit import log as logging +from cloudinit import mergers from cloudinit import util from cloudinit.settings import (PER_ALWAYS) LOG = logging.getLogger(__name__) +MERGE_HEADER = 'Merge-Type' +DEF_MERGERS = mergers.default_mergers() + class CloudConfigPartHandler(handlers.Handler): def __init__(self, paths, **_kwargs): - handlers.Handler.__init__(self, PER_ALWAYS) - self.cloud_buf = [] + handlers.Handler.__init__(self, PER_ALWAYS, version=3) + self.cloud_buf = None self.cloud_fn = paths.get_ipath("cloud_config") + self.file_names = [] + self.mergers = [DEF_MERGERS] def list_types(self): return [ handlers.type_from_starts_with("#cloud-config"), ] - def _write_cloud_config(self, buf): + def _write_cloud_config(self): if not self.cloud_fn: return - lines = [str(b) for b in buf] - payload = "\n".join(lines) - util.write_file(self.cloud_fn, payload, 0600) + # Capture which files we merged from... + file_lines = [] + if self.file_names: + file_lines.append("# from %s files" % (len(self.file_names))) + for fn in self.file_names: + file_lines.append("# %s" % (fn)) + file_lines.append("") + if self.cloud_buf is not None: + # Something was actually gathered.... + lines = [ + "#cloud-config", + '', + ] + lines.extend(file_lines) + lines.append(util.yaml_dumps(self.cloud_buf)) + else: + lines = [] + util.write_file(self.cloud_fn, "\n".join(lines), 0600) + + def _extract_mergers(self, payload, headers): + merge_header_headers = '' + for h in [MERGE_HEADER, 'X-%s' % (MERGE_HEADER)]: + tmp_h = headers.get(h, '') + if tmp_h: + merge_header_headers = tmp_h + break + # Select either the merge-type from the content + # or the merge type from the headers or default to our own set + # if neither exists (or is empty) from the later. + payload_yaml = util.load_yaml(payload) + mergers_yaml = mergers.dict_extract_mergers(payload_yaml) + mergers_header = mergers.string_extract_mergers(merge_header_headers) + all_mergers = [] + all_mergers.extend(mergers_yaml) + all_mergers.extend(mergers_header) + if not all_mergers: + all_mergers = DEF_MERGERS + return all_mergers + + def _merge_part(self, payload, headers): + next_mergers = self._extract_mergers(payload, headers) + # Use the merger list from the last call, since it is the one + # that will be defining how to merge with the next payload. + curr_mergers = list(self.mergers[-1]) + LOG.debug("Merging by applying %s", curr_mergers) + self.mergers.append(next_mergers) + merger = mergers.construct(curr_mergers) + if self.cloud_buf is None: + # First time through, merge with an empty dict... + self.cloud_buf = {} + self.cloud_buf = merger.merge(self.cloud_buf, + util.load_yaml(payload)) - def _handle_part(self, _data, ctype, filename, payload, _frequency): + def _reset(self): + self.file_names = [] + self.cloud_buf = None + self.mergers = [DEF_MERGERS] + + def handle_part(self, _data, ctype, filename, # pylint: disable=W0221 + payload, _frequency, headers): # pylint: disable=W0613 if ctype == handlers.CONTENT_START: - self.cloud_buf = [] + self._reset() return if ctype == handlers.CONTENT_END: - self._write_cloud_config(self.cloud_buf) - self.cloud_buf = [] + self._write_cloud_config() + self._reset() return - - filename = util.clean_filename(filename) - if not filename: - filename = '??' - self.cloud_buf.extend(["#%s" % (filename), str(payload)]) + try: + self._merge_part(payload, headers) + self.file_names.append(filename) + except: + util.logexc(LOG, "Failed at merging in cloud config part from %s", + filename) |