OASIS Mailing List ArchivesView the OASIS mailing list archive below
or browse/search using MarkMail.

 


Help: OASIS Mailing Lists Help | MarkMail Help

camp message

[Date Prev] | [Thread Prev] | [Thread Next] | [Date Next] -- [Date Index] | [Thread Index] | [List Home]


Subject: [OASIS Issue Tracker] Commented: (CAMP-32) CAMP needs to say something about the serialization of null attribute values and empty arrays


    [ http://tools.oasis-open.org/issues/browse/CAMP-32?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=31935#action_31935 ] 

Tobias Kunze  commented on CAMP-32:
-----------------------------------

I'm not sure JSON actually says anything about semantics, whether in this regard or otherwise. It certainly defines very clearly "null" and empty strings or arrays as valid values, so any dropping of such keys is probably an idiosyncrasy of the serialization/deserialization code used or may be configuration/a user preference. For instance, Jackson exposes this via JsonSerialize.Inclusion[1]. At any rate, googling "json serialization null" surfaces enough discord on exclusion or inclusion of null values to make me doubt that taking a side here is prudent.

BTW, if you want to exclude "null" and empty arrays, why not empty dictionaries and empty strings as well?

Whatever the technical issues, going back to the PHP extensions use case example, if an empty "extensions" key would be minimized (elided) by my deserialization library, I as a user would have to manually look up whether the actual resource represented by the PlatformComponentTemplate allows me to specify extensions. This would be a distinct drawback.

[1] http://jackson.codehaus.org/1.2.1/javadoc/org/codehaus/jackson/map/annotate/JsonSerialize.Inclusion.html


> CAMP needs to say something about the serialization of null attribute values and empty arrays
> ---------------------------------------------------------------------------------------------
>
>                 Key: CAMP-32
>                 URL: http://tools.oasis-open.org/issues/browse/CAMP-32
>             Project: OASIS Cloud Application Management for Platforms (CAMP) TC
>          Issue Type: Improvement
>          Components: Spec
>            Reporter: Gilbert Pilz
>            Assignee: Gilbert Pilz
>
> The following JSON:
> {
>   "uri" : "http://slc03lgx.us.oracle.com/campSrv/Assembly/9";,
>   "name" : "/examples",
>   "description" : null,
>   "created" : "2012-11-14T08:33-0800",
>   "tags": []
>   ...
> }
> Is semantically equivalent to:
> {
>   "uri" : "http://slc03lgx.us.oracle.com/campSrv/Assembly/9";,
>   "name" : "/examples",
>   "created" : "2012-11-14T08:33-0800",
>   ...
> }
> However, different languages and mappings treat these representations in different ways. For the sake of interoperability we should consider avoiding these differences by adding requirements to CAMP regarding the serialization of empty arrays and non-existent values.
> We could:
> 1.) say that clients and servers MUST NOT send either 'null' attributes or empty arrays
> 2.) say that clients and servers SHOULD NOT send either 'null' attributes or empty arrays
> 3.) say that clients and servers MUST NOT send 'null' attributes and SHOULD NOT send empty arrays
> 4.) say that clients and servers SHOULD NOT send 'null' attributes and MUST NOT send empty arrays
> We could also blow out the above choices with the additional factor of allowing clients and servers to have different behavior. For example "Clients MUST NOT send 'null' attributes but servers SHOULD accept them". I've had experience with this sort of thing (in the WS-I profiles) and it rapidly gets weird. IMO it is naturally outside the scope of any specification to define how one party in an interaction should behave in the face of non-compliant behavior on the part of another party. If a CAMP service implementation wanted to be "generous in what it receives", it should be free to do that, but I don't think we can mandate that behavior.

-- 
This message is automatically generated by JIRA.
-
If you think it was sent incorrectly contact one of the administrators: http://tools.oasis-open.org/issues/secure/Administrators.jspa
-
For more information on JIRA, see: http://www.atlassian.com/software/jira

        


[Date Prev] | [Thread Prev] | [Thread Next] | [Date Next] -- [Date Index] | [Thread Index] | [List Home]