'Model' Object is not iterable

Question

As soon as I click on a button that calls my view to edit the Row of the table in question shows me the error: 'Meumodel' Object is not iterable.

• I’m using Django 2.1.15
• Python 3.8.1
• SQL server database

py views.

def Alterar_Pessoa(request, id):
    visitantes = get_object_or_404(DadosPessoas, pk=id)
    form = PessoaForm(instance=visitantes)

    if(request.method == 'POST'):
        return False

    else:
        return render(request, 'portaria/cadastroPessoa.html', {'form': form, 'visitantes': visitantes})

Full error message:

TypeError at /portaria/alterarPessoa/18
'DadosPessoas' object is not iterable
Request Method: GET
Request URL:    http://127.0.0.1:8000/portaria/alterarPessoa/18
Django Version: 2.1.15
Exception Type: TypeError
Exception Value:    
'DadosPessoas' object is not iterable
Exception Location: C:\Users\leona\AppData\Roaming\Python\Python38\site-packages\django\template\defaulttags.py in render, line 165
Python Executable:  C:\Users\leona\AppData\Local\Programs\Python\Python38-32\python.exe
Python Version: 3.8.1
Python Path:    
['C:\\Users\\leona\\OneDrive\\Ambiente de '
 'Trabalho\\projeto\\MCS_JSP\\mcs\\MCS_Back',
 'C:\\Users\\leona\\AppData\\Local\\Programs\\Python\\Python38-32\\python38.zip',
 'C:\\Users\\leona\\AppData\\Local\\Programs\\Python\\Python38-32\\DLLs',
 'C:\\Users\\leona\\AppData\\Local\\Programs\\Python\\Python38-32\\lib',
 'C:\\Users\\leona\\AppData\\Local\\Programs\\Python\\Python38-32',
 'C:\\Users\\leona\\AppData\\Roaming\\Python\\Python38\\site-packages',
 'C:\\Users\\leona\\AppData\\Local\\Programs\\Python\\Python38-32\\lib\\site-packages']
Server time:    Sex, 10 Abr 2020 13:21:14 -0300


Error during template rendering
In template C:\Users\leona\OneDrive\Ambiente de Trabalho\projeto\MCS_JSP\mcs\MCS_Back\portaria\templates\portaria\cadastroPessoa.html, error at line 372

Linha 372: {% for visitante in visitantes %}

Answer 1

To popular the variable visitantes you’re using get_object_or_404() that behind the cloths will make a get() if you don’t find anything it will launch Http404 instead of Doesnotexist.

The problem is in get_object_or_404() use the get(). This is analogous to do:

DadosPessoas.objects.get(id=id)

The get() will bring an object of the type Data for he is doing a direct search for the id. The Dadospeople-like object is not, in fact, iterable.

It would have to be used then the filter() instead of get().

The filter() returns an object of type Queryset which in turn is iterable. Thus using the:

visitantes = get_list_or_404(DadosPessoas, pk=id)

Underneath the covers will be executed something like:

DadosPessoas.objects.filter(id=id)

Then returning an object with the right type. See the documentation for get_list_or_404() and examples.

If you are dealing with data from form the form of treatment is completely different and for this it is recommended the use of formsets.