ensure use of py yaml c extension for speed.

ensure use of py yaml c extension for speed.

Backwards compatible. Drops test time in half. Should improve speed
across the board, things like status will see marked improvements.

https://code.launchpad.net/~hazmat/juju/fast-yaml/+merge/123470

(do not edit description out of merge proposal)

[hazmat, 2012-09-10 03:41:21]

Please take a look.

[gz, 2012-09-10 15:01:54]

Looks like a good improvement, I like that this also sorts out the confusion
over whether to use dump/load or safe_dump/safe_load at the same time.

I would have been tempted to name the wrapper module juju.lib.yaml to avoid
touching most lines, but this way means you did look at all the callers at
least.

There are several callsites that still use the yaml module functions and pass in
a Loader or Dumper, apart from the one noted below, shouldn't they all be
changed to using juju.lib for consistency?

https://codereview.appspot.com/6493100/diff/1/juju/charm/config.py
File juju/charm/config.py (right):

https://codereview.appspot.com/6493100/diff/1/juju/charm/config.py#newcode80
juju/charm/config.py:80: raw_data = yaml.load(data, Loader=yaml.CSafeLoader)
Why not use dump from juju.lib here rather than specifying the loader? Will need
the yaml import for the Mark below anyway, but seems best to consistently use
the same loader.

https://codereview.appspot.com/6493100/diff/1/juju/control/constraints_get.py
File juju/control/constraints_get.py (right):

https://codereview.appspot.com/6493100/diff/1/juju/control/constraints_get.py...
juju/control/constraints_get.py:73: yaml.dump(result, sys.stdout,
Dumper=yaml.CSafeDumper)
I'd dump using the juju.lib function and write to stout separately afterwards
here.

https://codereview.appspot.com/6493100/diff/1/juju/control/status.py
File juju/control/status.py (right):

https://codereview.appspot.com/6493100/diff/1/juju/control/status.py#newcode581
juju/control/status.py:581: data, filelike, default_flow_style=False,
Dumper=yaml.CSafeDumper)
This looks like the only place that really wants extra args to dump, leaving
this as a special case seems fine.

https://codereview.appspot.com/6493100/diff/1/juju/lib/serializer.py
File juju/lib/serializer.py (right):

https://codereview.appspot.com/6493100/diff/1/juju/lib/serializer.py#newcode5
juju/lib/serializer.py:5: def dump(*args, **kw):
I'd be tempted to make this just take a dict rather than passing through args
and kwargs.

https://codereview.appspot.com/6493100/diff/1/juju/lib/serializer.py#newcode9
juju/lib/serializer.py:9: def load(*args, **kw):
Likewise, would make this just take a string.

[hazmat, 2012-09-14 15:34:27]

Please take a look.

[jimbaker, 2012-09-14 16:03:36]

+1, LGTM, nice speedup and a clean transition to the C extensions. Just need to
take care of the two trivials where CSafeLoader/CSafeDumper is used instead of
the equivalent juju.lib.serializer wrappers.

https://codereview.appspot.com/6493100/diff/5002/juju/environment/config.py
File juju/environment/config.py (right):

https://codereview.appspot.com/6493100/diff/5002/juju/environment/config.py#n...
juju/environment/config.py:178: config = yaml.load(content,
Loader=yaml.CSafeLoader)
Use juju.lib.serializer.load instead

https://codereview.appspot.com/6493100/diff/5002/juju/environment/config.py#n...
juju/environment/config.py:313: return yaml.dump(config,
Dumper=yaml.CSafeDumper)
Use juju.lib.serializer.dump instead