How can I the best filter out data and make a collection of paintings

Hello,

I have ask this before on the discord channels but I cannot find there the solutions anymore.

I try to make a website that displays the paintings of the Rijksmuseaum in Amsterdam.
That provides a json response

So I do :

| json paintingCollection |

json := (NeoJSONReader fromString: (ZnEasy get: 'https://www.rijksmuseum.nl/api/nl/collection?key=14OGzuak&format=json&type=schilderij&toppieces=True') contents) at: #artObjects.

so I still have this json :

{
      "links": {
        "self": "https://www.rijksmuseum.nl/api/nl/collection/SK-C-5",
        "web": "https://www.rijksmuseum.nl/nl/collection/SK-C-5"
      },
      "id": "nl-SK-C-5",
      "objectNumber": "SK-C-5",
      "title": "Schutters van wijk II onder leiding van kapitein Frans Banninck Cocq, bekend als de ‘Nachtwacht’",
      "hasImage": true,
      "principalOrFirstMaker": "Rembrandt Harmensz. van Rijn",
      "longTitle": "Schutters van wijk II onder leiding van kapitein Frans Banninck Cocq, bekend als de ‘Nachtwacht’, Rembrandt Harmensz. van Rijn, 1642",
      "showImage": true,
      "permitDownload": true,
      "webImage": {
        "guid": "92253da1-794d-49f4-9e3c-e4c160715f53",
        "offsetPercentageX": 50,
        "offsetPercentageY": 100,
        "width": 2500,
        "height": 2034,
        "url": "http://lh6.ggpht.com/wwx2vAS9DzFmmyeZefPjMtmCNOdjD80gvkXJcylloy40SiZOhdLHVddEZLBHtymHu53TcvqJLYZfZF7M-uvoMmG_wSI=s0"
      },
      "headerImage": {
        "guid": "29a2a516-f1d2-4713-9cbd-7a4458026057",
        "offsetPercentageX": 50,
        "offsetPercentageY": 50,
        "width": 1920,
        "height": 460,
        "url": "http://lh5.ggpht.com/SgH3Qo-vYI8GGm7-b-Qt6lXgsCAIoU2VDRwO5LYSBVNhhbZCetcvc88ZPi518MTy0MHDrna4X4ZC1ymxVJVpzps8gqw=s0"
      },
      "productionPlaces": []
    },

but then as a object 

now I wonder how I can change the code with I think a object named Painting thatI onky want to use these
fields :  objectNumber, principalOrFirstMaker and webImage/url 
so that I have a collection of paintings with only these things

Roelof
 
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