Making all Blob/Bucket getters fail gracefully if keys don't exist.

[dhermes]

Also replacing uses of dict.copy() (shallow) with copy.deepcopy().

[coveralls]

Coverage remained the same at 100.0% when pulling 873ec53 on dhermes:prevent-property-key-error-in-storage into 3af46b1 on GoogleCloudPlatform:master.

[tseaver]

ISTM that returning None from the getters breaks their contract a bit: we could either change the :rtype: to append or None, or else return defaults which match the documented type.

[dhermes]

@tseaver I imagine a future where people use their own projection or fields, e.g.

blob.reload(fields=['generation', 'metageneration'])

and then all other values are unset.

I think changing the rtype is the right way to go here.

[dhermes]

@tseaver I updated the docstrings and pushed again. I also coerced some values to ints, since int64 in JSON is a string even though it should be an int (due to JS precision problems).

I also wanted to convert the timestamps to datetime.datetime but was worried that using

datetime.datetime.strptime(value, '%Y-%m-%dT%H:%M:%S.%fZ')

would be insufficient for values returned by the backend (AFAIK the only contract is that they will be valid RFC3339).

[coveralls]

Coverage remained the same at 100.0% when pulling 2971484 on dhermes:prevent-property-key-error-in-storage into fd06f16 on GoogleCloudPlatform:master.

[tseaver]

Aside from the worry about PATCH w/ None, LGTM.

[dhermes]

PATCH with None effectively "unsets" the property. But we would only send None if it was explicitly set by the user.

I'm AFK now but would like to test out what happens if None is sent for a required property.

[dhermes]

@tseaver What is the implication of my answer? How to move forward?

[tseaver]

We should figure out what happens when {'metadata': null} is the payload for a PATCH request where metadata had already been set. If the back-end barfs, we shouldn't allow None as a value in the setter.

[dhermes]

@tseaver I was already pretty sure what happened, but I verified via https://developers.google.com/apis-explorer/#p/storage/v1/storage.objects.patch by sending "metadata: null" after previously setting metadata to {'foo': 'bar'}. It did as expected: it simply "unset" the metadata value.

[tseaver]

OK. ISTM we can just mirror that, then (the json module already marshalls Python None as null).

[dhermes]

Yep, we get it for free. Remaining hangups?

[tseaver]

Nope.