Return QuerySet with extra pagination fields-CodePudding

My get_queryset return this. Also, this fields with ID's are foreign keys serialized.

[
    {
        "id": 1389,
        "nome": "Curso teste",
        "nivel": {
            "id": 5,
            "nome": "Ensino Fundamental II"
        },
        "modalidade": {
            "id": 4,
            "nome": "Presencial"
        },
        "periodo": {
            "id": 5,
            "nome": "Matutino"
        },
        "ano": {
            "id": 21,
            "nome": "12º Semestre"
        },
        "instituicao": {
            "id": 35,
            "nome": "Fncit-escola"
        }
    }
]

I want to add to each object an extra pagination object, and it would be like this object below.

But get_queryset do not accept this kind of object, and if I use just get, and serialize the queryset, it will not come with the ForeignKeys serialized, it will return only the id's of the Foreign keys.

Anyone knows how do I return an object like this?

   [
    "bolsas":{
        "id": 1389,
        "nome": "Curso teste",
        "nivel": {
            "id": 5,
            "nome": "Ensino Fundamental II"
        },
        "modalidade": {
            "id": 4,
            "nome": "Presencial"
        },
        "periodo": {
            "id": 5,
            "nome": "Matutino"
        },
        "ano": {
            "id": 21,
            "nome": "12º Semestre"
        },
        "instituicao": {
            "id": 35,
            "nome": "Fncit-escola"
        }
    },
    "pagination": {
       "elements": 1
     }
]

I want to return this object:

        retorno = {
        'bolsas': bolsas,
        'paginacao':{
           'ultimo': True if int(totalElementos) - int(limite) == 1 else False,
           'primeiro': True if pagina == 0 and int(limite) == 1 else False,
           'totalPaginas': totalPaginas,
           'totalElementos': totalElementos,
           'elementos': elementos,
           'offset': pagina

        } 
    }

Where bolsas is the queryset

CodePudding user response：

On pure Django you have the Paginator class:

>>> from django.core.paginator import Paginator
>>> objects = ['john', 'paul', 'george', 'ringo']
>>> p = Paginator(objects, 2)

>>> p.count
4
>>> p.num_pages
2
>>> type(p.page_range)
<class 'range_iterator'>
>>> p.page_range
range(1, 3)

If you're using django-rest-framework (DRF), you have a few more options and more flexibility to customize your paginator. By limit and offset, with next, cursor pagination or some custom paginator.

Having said that, from your code examples, maybe it seems what you're looking for is a Serializer and not a Paginator? You could also leverage DRF for that or use either a simple object constructor or a Manager.

CodePudding user response：

I serialized the queryset like this:

bolsas_serialized = BolsaSerializer(bolsas, many=True).data

and then could use like this

        retorno = {
        'bolsas': bolsas_serialized,
        'paginacao':{
           'ultimo': True if int(totalElementos) - int(limite) == 1 else False,
           'primeiro': True if pagina == 0 and int(limite) == 1 else False,
           'totalPaginas': totalPaginas,
           'totalElementos': totalElementos,
           'elementos': elementos,
           'offset': pagina

        } 
    }


return Response(retorno)