Re: [Pharo-users] complex json parsing.

[Roelof Wobben]

Op 12-3-2019 om 18:46 schreef Ben Coman: On Wed, 13 Mar 2019 at 00:43, Roelof Wobben <r.wob...@home.nl> wrote: > I did try to make this idea work but now im complete lost. > > Right now the collection that should contain the objectNumbers is total empty > anyone who can see where I went wrong. > > I included my code so far. A few things... !Paintings class methodsFor: 'instance creation' stamp: 'RoelofWobben 3/12/2019 17:26'! getImagesDataFromJSON: json | instance | instance := Painting new. (json at: #values) do: [ :artObjectJson |  | painting | painting := Painting new. painting imageUrl: (json at: #name). instance addPainting: painting ]. ^ instance! ! You are adding a painting to a painting, which semantically makes no sense. i.e. where #addPainting: is sent to "instance" , that is holding a Painting. I would not expect your Painting class to have a method addPainting: Paintings should have that method. btw, Stop using "instance" as a variable name.   Its as bad as variables named "a", "i", "t", "z" - it provides no semantic context. -------------------- Object subclass: #Paintings instanceVariableNames: 'paintings numbers' Paintings class instanceVariableNames: 'numbers paintings'! You've defined these variables on both the instance-side and class-side. I'll hazard a guess that you should delete the class-side definition.  ---------------------------------- TBApplicationRootComponent initialize!Object subclass: #Painting instanceVariableNames: 'imageUrl' Why are you *not* storing objectNumber inside each Painting? What is the relationship between paintings and objectNumbers? Is it one-to-many or one-to-one? ------------------- !Paintings methodsFor: 'instance creation' stamp: 'RoelofWobben 3/11/2019 08:05'! initialize super initialize. numbers := OrderedCollection new! ! Why do you *not* initialize variable "paintings" to "OrderedCollection new" ? Aren't you dealing with a collection of paintings? ---------------- There is lots more confusing me here, so before going further, in a fresh new image, can you load NeoJSON and the attached fileout. Then in Playground do...     collectionUrl :=  'https://www.rijksmuseum.nl/api/nl/collection?key=14OGzuak&format=json&type=schilderij&toppieces=True'.     json := NeoJSONReader fromString: (ZnEasy get: collectionUrl) contents.     paintings := Paintings fromJSON: json.     paintings inspect. and then debug trace through that whole thing. Is that what you were trying to do?  Or have I got the wrong end of the stick? cheers -ben Oke, I try to tell what I want Right now I only want to fetch the objectNumber is a collection. so I can use that in a later step. There is a one to one relationship between the objectNumber and a Painting I do not use the imageUrl found on this url because it's to big . So what I try now is first put all the objectNumber in a collection and use that collection on a second url to fetch a image of the right size I hope im clear what I try to do in this step so numbers should be a collection of objectNumbers and paintings a collection of painting with the info I need so to recap this one must give me a collection of objectNumbers : 'https://www.rijksmuseum.nl/api/nl/collection?key=14OGzuak&format=json&type=schilderij&toppieces=True'. and the objectNumbers I can use for this url :  https://www.rijksmuseum.nl/api/nl/collection/<one objectNumber/tiles?key=14OGzuak&format=json and I do not store the objectNumber in Paintings because I do not use it to display it in a seaside project. Roelof