[OASIS Issue Tracker] (ODATA-879) Support Arrays of Arrays

[OASIS Issues Tracker <workgroup_mailer@lists.oasis-open.org>]

    [ https://issues.oasis-open.org/browse/ODATA-879?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=65208#comment-65208 ] 

Michael Pizzo commented on ODATA-879:
-------------------------------------

Assertions:
1) For typical JSON consumers, expanding a primitive value or collection into an object is going to be unexpected and undesired.  We would need a client directive to say that it was okay to change a non-structured object into a structure object.
2) Any way of annotating a primitive is going to be cumbersome, should minimize the number of cases where a primitive value has to be annotated.
3) Parallel arrays are undesireable, particularly if large, because the service may need to make multiple passes through data (if even possible); one to build the annotations and one to build the value array, and clients will need to read both to understand either of them.

Variants:
1) Consider supporting arrays of arrays of primitives, but not allowing them to be annotated.
2) Support a syntax for externally annotating non-structural members of an ordered collection by adding a peer to the array property that uses the index as the property name being annotated.  

Option1:
{
        "foo": [[2, 7], [1, null, 18.34], [7, 2.14, 6, 89]],
        "foo@": {
            "0@count": 2,
            "1@count": 3,
            "1/2@myAnnotation": "Couldn't read handwriting",
            "2@count":4
}
Option 2:
    {
        "foo": [[2, 7], [1, null, 18.34], [7, 2.14, 6, 89]],
        "foo@": {
            "0@count": 2,
            "1@count": 3,
            "1@" : { "2@myAnnotation": "Couldn't read handwriting"},
            "2@count":4
    }



> Support Arrays of Arrays
> ------------------------
>
>                 Key: ODATA-879
>                 URL: https://issues.oasis-open.org/browse/ODATA-879
>             Project: OASIS Open Data Protocol (OData) TC
>          Issue Type: Bug
>          Components: OData CSDL, OData JSON Format
>    Affects Versions: V4.0_ERRATA02
>            Reporter: Michael Pizzo
>            Assignee: Michael Pizzo
>             Fix For: V4.01_CSD02
>
>
> There are scenarios where it's convenient to represent something as an array of arrays. In JSON this would look as:
> [["foo1","bar1"],["foo2","bar2"]]
> or
> [[{"foo":"foo1"},{"bar":"bar1"}],[{"foo":"foo2"},{"bar":"bar2"}]]
> Currently services must represent these as arrays of complex types that have array properties. In JSON, the result looks like:
> [{"value":["foo1","bar1"]},{"value":["foo2","bar2"]}]
> or
> [{"value":[{"foo":"foo1"},{"bar":"bar1"}]},{"value":[{"foo":"foo2"},{"bar":"bar2"}]}]
> If we are trying to make JSON representation as close as possible to a custom representation we would need to support the former syntax (without the "value" objects).
> One problem with arrays of arrays in JSON is that we don't have a way to annotate the (array) items within the array. For example, we couldn't add count, nextLink, etc. for the inner arrays..



--
This message was sent by Atlassian JIRA
(v6.2.2#6258)