SDMX 3.0: implement "feature 029 Improving API data queries" for SDMX-JSON messages

[dosse]

In order to support the new requirement, it is proposed to:

structure message changes: No impact.

data message changes:

• Add support for multiple keys
  No impact.
• Extend the context of data retrieval
  The data message already allows specifying links to DSD or ProvisionAgreement. However, currently, the data message only allows retrieving the data for one artefact. The possibility to allow for several artefacts needs to be added. The following is the proposal to allow including several structural artefacts instead of one and to link from the structure object to the related dataSet object(s):

"data":{
    "structures":[
        {
            "links":[
                {
                    # Urn --> dataflow, data structure definition or provision agreement #
                }
            ],
            "dimensions":{
                # dimensions object #
            },
            "measures":{
                # measures object #
            },
            "attributes":{
                # attributes object #
            },
            "annotations":[
                {
                    # annotation object #
                }
            ],
            "dataSets": [0,1]   # Contains the indexes of the related dataSet objects in the dataSets array
        }
    ],
    "dataSets":[
        {
            "structure": 0, # Contains the index of the related structure object in the structures array
            "action":"Information",
            "attributes":[
                "…"
            ],
            "dimensionGroupAttributes":{
                # dimensionGroupAttributes object #
            },
            "series":{
                # series object #
            },
            "observations":{
                # observations object #
            }
        },
        {
            "structure": 0, # Contains the index of the related structure object in the structures array
            "action":"Delete",
            "attributes":[
                "…"
            ],
            "dimensionGroupAttributes":{
                # dimensionGroupAttributes object #
            },
            "series":{
                # series object #
            },
            "observations":{
                # observations object #
            }
        }
    ]
}

• Add a “cube-based” data retrieval, in addition to the current “key-based” one No impact.
• Harmonizing separators No impact.

[dosse]

Released