From f51e04ba97a42782e6a0e973488290552346387f Mon Sep 17 00:00:00 2001 From: Joshua Harlow Date: Fri, 19 Jul 2013 16:32:48 -0700 Subject: Add the ability to merge with jsonpatch. Jsonpatch is a new RFC standard for merging json-like structures which the cloud-init cloud-config is one such structure. To use this in a limited fashion (to start) add the ability for the cloud-config handler to accept this content-type and use it as an alternate way to merge new cloud-config sections into the accumulated cloud-config. LP: #1200476 --- cloudinit/handlers/cloud_config.py | 25 ++++++++++++++++++++----- 1 file changed, 20 insertions(+), 5 deletions(-) (limited to 'cloudinit') diff --git a/cloudinit/handlers/cloud_config.py b/cloudinit/handlers/cloud_config.py index c97ca3e8..8d1ba37f 100644 --- a/cloudinit/handlers/cloud_config.py +++ b/cloudinit/handlers/cloud_config.py @@ -20,6 +20,8 @@ # You should have received a copy of the GNU General Public License # along with this program. If not, see . +import jsonpatch + from cloudinit import handlers from cloudinit import log as logging from cloudinit import mergers @@ -50,6 +52,9 @@ MERGE_HEADER = 'Merge-Type' # This gets loaded into yaml with final result {'a': 22} DEF_MERGERS = mergers.string_extract_mergers('dict(replace)+list()+str()') +# See: https://tools.ietf.org/html/rfc6902 +JSON_PATCH_CTYPE = 'application/json-patch+json' + class CloudConfigPartHandler(handlers.Handler): def __init__(self, paths, **_kwargs): @@ -59,9 +64,11 @@ class CloudConfigPartHandler(handlers.Handler): self.file_names = [] def list_types(self): - return [ + ctypes_handled = [ handlers.type_from_starts_with("#cloud-config"), + JSON_PATCH_CTYPE, ] + return ctypes_handled def _write_cloud_config(self): if not self.cloud_fn: @@ -107,13 +114,15 @@ class CloudConfigPartHandler(handlers.Handler): all_mergers = DEF_MERGERS return (payload_yaml, all_mergers) + def _merge_patch(self, payload): + patch = jsonpatch.JsonPatch.from_string(payload) + LOG.debug("Merging by applying json patch %s", patch) + self.cloud_buf = patch.apply(self.cloud_buf, in_place=False) + def _merge_part(self, payload, headers): (payload_yaml, my_mergers) = self._extract_mergers(payload, headers) LOG.debug("Merging by applying %s", my_mergers) merger = mergers.construct(my_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, payload_yaml) def _reset(self): @@ -130,7 +139,13 @@ class CloudConfigPartHandler(handlers.Handler): self._reset() return try: - self._merge_part(payload, headers) + # First time through, merge with an empty dict... + if self.cloud_buf is None or not self.file_names: + self.cloud_buf = {} + if ctype == JSON_PATCH_CTYPE: + self._merge_patch(payload) + else: + self._merge_part(payload, headers) # Ensure filename is ok to store for i in ("\n", "\r", "\t"): filename = filename.replace(i, " ") -- cgit v1.2.3