Django - Model field keeps the same value! - django

When I assign a value to an variable of a Field object, why when I reload the ModelForm isn't reassigned to default?
File
class CustomFile(ImageFile, FieldFile):
def save(self, name, content, save = True):
if self.field.override_name:
self(CustomFile, self).save(self.field.override_name, content, save = save)
else:
self(CustomFile, self).save(generate_name(self.instance, name), content, save = save)
Field
class CustomImageField(ImageField):
attr_class = CustomFile
def __init__(self, overrided_name, *args, **kwargs):
self.overrided_name = overrided_name
super(CustomImageField, self).__init__(*args, **kwargs)
Model
class Test(models.Model):
email = models.EmailField()
file = CustomImageField()
AdminForm
class TestForm(ModelForm):
def __init__(self, *args, **kwargs):
super(TestForm, self).__init__(*args, **kwargs)
self.old_instance = self.instance
Admin
class TestAdmin(Test):
form = TestForm
def save_model(self, request, obj, form, change):
if form.old_instance:
form.old_instance.file.delete(save = True)
form.old_instance.file.field.override_name = form.old_instance.name
obj.save()
admin.site.register(Test, TestAdmin)
My problem is that every image I will upload will have the same name, until I restart the server!..
Why the object doesn't change?! In particular the Field object... when I trace it will result the same object .
I've solved it like so:
class CustomFile(ImageFile, FieldFile):
def save(self, name, content, save = True):
if self.field.override_name:
self(CustomFile, self).save(self.field.override_name, content, save = save)
self.field.override_name = None
else:
self(CustomFile, self).save(generate_name(self.instance, name), content, save = save)
I'm using Django 1.2.6, Python 2.6 and Windows!

I am just guessing, but isnt this part of code wrong?
form = TestForm
Should not it be creating an instance instead of referencing to class?
form = TestForm()
or same thing here?
attr_class = CustomFile - > attr_class = CustomFile()

Related

Add a field value outside form in Django

Whenever I have to add a value to the instance of a form obtained from the context or from the URL I do it in the following way, using form.instance.
class PreguntaForm(forms.ModelForm):
class Meta:
model = Pregunta
fields = ('etiqueta', 'grupo', 'tipo_pregunta', 'opciones', 'mostrar_tabla', 'activo')
def __init__(self, *args, **kwargs):
cuestionario = kwargs.pop('cuestionario', False)
super(PreguntaForm, self).__init__(*args, **kwargs)
self.fields['grupo'].queryset = Grupo.objects.filter(cuestionario=cuestionario)
class PreguntaNueva(InfoPregunta, CreateView):
form_class = PreguntaForm
encabezado = 'Nueva Pregunta'
model = Pregunta
def get_form_kwargs(self):
kwargs = super(PreguntaNueva, self).get_form_kwargs()
kwargs['cuestionario'] = self.dame_cuestionario()
return kwargs
def form_valid(self, form):
form.instance.cuestionario = self.dame_cuestionario()
return super(PreguntaNueva, self).form_valid(form)
The problem that arises now is that I want to perform a check CreateView and EditView. To DRY, I want to do it in the clean method of the model, but the value that I assign to form.instance.cuestionario, is not available within the clean method. How could I do it? This value must not be edited by the user in any case.
Yes it is, you pass it in via get_form_kwargs; you just need to assign it to an instance variable in the form's __init__.
def __init__(self, *args, **kwargs):
self.cuestionario = kwargs.pop('cuestionario', False)
super(PreguntaForm, self).__init__(*args, **kwargs)
self.fields['grupo'].queryset = Grupo.objects.filter(cuestionario=self.cuestionario)
def clean(self):
# do something with self.cuestionario

How to populate a field in a django model

I have a Django project in which I have a view subclassed from the Django CreateView class. This view is used to upload a file to the server, and uses an UploadedFile model which I have created. The UploadedFile also needs to be associated with a project.
The project id is passed in as part of the URL: (r'^projects/(?P<proj_key>\d+)/$', UploadedFileCreateView.as_view(), {}, 'upload-new')
The problem is that I am not sure where the appropriate place is to associate this key with my model. Is there a method of CreateView or one of its ancestors that I should override that creates the model, or can this be done anywhere in my code in one of the methods I already override (this feels hacky though).
Furthermore, the project attribute of my UploadedFile is defined as a ForeignKey of type Project. How do I get the Project to associate with it?
Here is my model definition:
class Project(models.Model):
"""This is a project that is owned by a user and contains many UploadedFiles."""
name = models.CharField(max_length=200)
class UploadedFile(models.Model):
"""This represents a file that has been uploaded to the server."""
STATE_UPLOADED = 0
STATE_ANNOTATED = 1
STATE_PROCESSING = 2
STATE_PROCESSED = 4
STATES = (
(STATE_UPLOADED, "Uploaded"),
(STATE_ANNOTATED, "Annotated"),
(STATE_PROCESSING, "Processing"),
(STATE_PROCESSED, "Processed"),
)
status = models.SmallIntegerField(choices=STATES,
default=0, blank=True, null=True)
file = models.FileField(upload_to=settings.XML_ROOT)
project = models.ForeignKey(Project)
def __unicode__(self):
return self.file.name
def name(self):
return os.path.basename(self.file.name)
def save(self, *args, **kwargs):
if not self.status:
self.status = self.STATE_UPLOADED
super(UploadedFile, self).save(*args, **kwargs)
def delete(self, *args, **kwargs):
os.remove(self.file.path)
self.file.delete(False)
super(UploadedFile, self).delete(*args, **kwargs)
Here is my view definition:
class UploadedFileCreateView(CreateView):
model = UploadedFile
def form_valid(self, form):
logger.critical("Inside form_valid")
self.object = form.save()
f = self.request.FILES.get('file')
data = [{'name': f.name,
'url': settings.MEDIA_URL + "files/" + f.name.replace(" ", "_"),
'project': self.object.project.get().pk,
'delete_url': reverse('fileupload:upload-delete',
args=[self.object.id]),
'delete_type': "DELETE"}]
response = JSONResponse(data, {}, response_mimetype(self.request))
response['Content-Disposition'] = 'inline; filename=files.json'
return super(UploadedFileCreateView, self).form_valid(form)
def get_context_data(self, **kwargs):
context = super(UploadedFileCreateView, self).get_context_data(**kwargs)
return context
You could do it right where you are calling form.save(). Just pass commit=False so that it won't save it to the db until you add the project id. For example:
self.object = form.save(commit=False)
self.object.project_id = self.kwargs['proj_key']
self.object.save()
Just make sure your form excludes the project field.
EDIT: to exclude the field, add an excludes variable to the form meta class:
class UploadedFileForm(forms.ModelForm):
class Meta:
model = UploadedFile
excludes = ('project',)

Django - MultipleCheckBoxSelector with m2m field - How to add object instead of save_m2m()

I use inlineformset_factory with a custom form option in order to change the queryset and the widget of a m2m field, ie: ezMap. I want the form to give the user the option to add or remove the current selected_map to the m2m field with CheckBoxSelectMultiple widget. However, I dont want to give the user the ability to remove other objects that were already there. The problem is when I save the formset with formset.save_m2m(), it overides the field and erase all objects that were already saved.
How could I just add a new object without erasing others?
models: (some of unecessary fields were removed)
class Shapefile(models.Model):
filename = models.CharField(max_length=255)
class EzMap(models.Model):
map_name = models.SlugField(max_length=50)
layers = models.ManyToManyField(Shapefile, verbose_name='Layers to display', null=True, blank=True)
class LayerStyle(models.Model):
styleName = models.SlugField(max_length=50)
layer = models.ForeignKey(Shapefile)
ezMap = models.ManyToManyField(EzMap)
forms:
class polygonLayerStyleFormset(forms.ModelForm):
add_to_map = forms.BooleanField(required=False)
def __init__(self, *args, **kwargs):
self.map_selected = kwargs.pop("map_selected", None)
super(polygonLayerStyleFormset, self).__init__(*args, **kwargs)
self.fields['conditionStyle'].help_text = "Put * if you want to select the entire table"
self.fields['ezMap'].widget = forms.CheckboxSelectMultiple()
self.fields['ezMap'].queryset = EzMap.objects.filter(id=self.map_selected.id)
self.fields['ezMap'].help_text =""
class Meta:
model = LayerStyle
def save(self, *args, **kwargs):
instance = super(polygonLayerStyleFormset, self).save(*args, **kwargs)
instance.add_to_map = self.cleaned_data['add_to_map']
return instance
ftlStylePolygonFormset = inlineformset_factory(Shapefile, LayerStyle, can_delete=True, extra=1, max_num=5,
fields = ['styleName', 'conditionStyle', 'fillColor', 'fillOpacity', 'strokeColor', 'strokeWeight', 'ezMap'], form=polygonLayerStyleFormset)
views:
def setLayerStyle(request, map_name, layer_id):
map_selected = EzMap.objects.get(map_name=map_name, created_by=request.user)
layer_selected = Shapefile.objects.get(id=layer_id)
layerStyle_selected = LayerStyle.objects.filter(layer=layer_selected)
styleFormset = ftlStylePolygonFormset
if request.POST:
formset = styleFormset(request.POST, instance=layer_selected)
if formset.is_valid():
instances = formset.save()
for instance in instances:
if instance.add_to_map:
instance.ezMap.add(map_selecte)
else:
instance.ezMap.remove(map_selected)
save_link = u"/ezmapping/map/%s" % (map_name)
return HttpResponseRedirect(save_link)
else:
formset = styleFormset(instance=layer_selected)
#set initial data for add_to_map
for form in formset:
if form.instance.pk:
if map_selected in form.instance.ezMap.all():
form.fields['add_to_map'].initial = {'add_to_map': True}
I am confused as to what you're doing with the ezMap form field. You set its queryset to a single-element list, then use a CheckboxSelectMultiple widget for it. Are you setting up to let the user deselect that matching map, but not add new ones?
To do this at initialization, you need to define a custom base formset class and pass that in as the formset argument to your factory.
from django.forms.models import BaseInlineFormSet
class polygonLayerStyleForm(forms.ModelForm):
def __init__(self, *args, **kwargs):
self.map_selected = kwargs.pop("map_selected", None)
super(polygonLayerStyleForm, self).__init__(*args, **kwargs)
self.fields['conditionStyle'].help_text = "Put * if you want to select the entire table"
self.fields['ezMap'].widget = forms.CheckboxSelectMultiple()
self.fields['ezMap'].queryset = EzMap.objects.filter(id=self.map_selected.id)
self.fields['ezMap'].help_text =""
class Meta:
model = LayerStyle
class polygonLayerStyleFormset(BaseInlineFormSet):
def __init__(self, *args, **kwargs):
self.map_selected = kwargs.pop("map_selected", None)
super(polygonLayerStyleFormset, self).__init__(*args, **kwargs)
def _construct_form(self, i, **kwargs):
kwargs['map_selected'] = self.map_selected
return super(polygonLayerStyleFormset, self)._construct_form(i, **kwargs)
ftlStylePolygonFormset = inlineformset_factory(Shapefile, LayerStyle, formset=polygonLayerStyleFormset, form=polygonLaterStyleForm, # and other arguments as above
)
It might be simpler to just go through the formset forms and directly change the field's queryset after creating it in your view:
formset = ftlStylePolygonFormset(instance=layer_selected)
for form in formset.forms:
form.fields['ezMap'].queryset = EzMap.objects.filter(id=map_selected.id)
Speaking of which, the usual convention is to split the POST and GET cases in the view:
from django.shortcuts import render
def setLayerStyle(request, map_name, layer_id):
map_selected = EzMap.objects.get(map_name=map_name, created_by=request.user)
layer_selected = Shapefile.objects.get(id=layer_id)
layerStyle_selected = LayerStyle.objects.filter(layer=layer_selected)
if request.method == 'POST':
formset = ftlStylePolygonFormset(request.POST, instance=layer_selected, map_selected=map_selected)
if formset.is_valid():
instances = formset.save()
save_link = u"/ezmapping/map/%s" % (map_name)
return HttpResponseRedirect(save_link)
else:
formset = ftlStylePolygonFormset(instance=layer_selected, map_selected=map_selected)
return render(request, "ezmapping/manage_layerStyle.html", {'layer_style': layerStyle_selected, 'layerStyleformset': formset, 'layer': layer_selected})
And it's better to use the redirect shortcut to reverse lookup a view for your redirect on success rather than hardcode the target URL. And to use get_object_or_404 or some equivalent when accessing objects based on URL arguments - right now a bogus URL will trigger an exception and give the user a 500 status error, which is undesirable.
To conditionally add to the ezMap relationship:
class polygonLayerStyleForm(forms.ModelForm):
add_to_map = forms.BooleanField()
def save(self, *args, **kwargs):
instance = super(polygonLayerStyleForm, self).save(*args, **kwargs)
instance.add_to_map = self.cleaned_data['add_to-map']
return instance
Then in the view:
instances = formset.save()
for instance in instances:
if instance.add_to_map:
instance.ezMap.add(map_selected)
You could also do the add call in the save method, but then you'd have to set the map as member data sometime previously - and more importantly, deal with the commit=False case.

Django ModelForm with field overwrite does not post data

So, I have the following form:
class DesignItemForm (forms.ModelForm):
def __init__(self, *args, **kwargs):
super(DesignItemForm, self).__init__(*args, **kwargs)
CHOICES=[(i,i) for i in range(MAX_DESIGN_ITEM_QUANTITY)]
self.fields['quantity'] = forms.ChoiceField(choices=CHOICES)
class Meta:
model = DesignItem
fields = ('quantity','trackable',)
My view:
d = Design.object.get(slug=fromInput)
....
DesignItemInlineFormSet = inlineformset_factory(Design, DesignItem, fk_name="design", form=DesignItemForm,)
if request.method == "POST":
formset = DesignItemInlineFormSet(request.POST, request.FILES, instance=d)
if formset.is_valid():
formset.save()
DesignItemInlineFormSet(instance=d)
As you can tell, in my form, I overwrote the quantity field to be a drop down instead of an integer field.
For some reason, when I submit the form, the data is not updated in the database. However, if I change the form to the following, it works (of course, it doesn't have the dropdowns I want, but it posts to the db). Why is this, and how do I fix it?
class DesignItemForm (forms.ModelForm):
def __init__(self, *args, **kwargs):
super(DesignItemForm, self).__init__(*args, **kwargs)
# CHOICES=[(i,i) for i in range(MAX_DESIGN_ITEM_QUANTITY)]
# self.fields['quantity'] = forms.ChoiceField(choices=CHOICES)
class Meta:
model = DesignItem
fields = ('quantity','trackable',)
EDIT: Here is the DesignItem model:
class DesignItem(models.Model):
"""Specifies how many of an item are in a design."""
design = models.ForeignKey(Design, related_name="items")
quantity = models.PositiveIntegerField(default=1)
trackable = models.ForeignKey(Trackable, related_name="used")
have you tried just overriding the widget instead of the whole field?
i guess you want a select widget
def __init__(self, *args, **kwargs):
super(DesignItemForm, self).__init__(*args, **kwargs)
CHOICES=[(i,i) for i in range(MAX_DESIGN_ITEM_QUANTITY)]
self.fields['quantity'].widget = forms.Select(choices=CHOICES)

Django snippets. How to use?

explain me please how to use it in my Admin?
You can just create a custom ModelForm for your model, with the following:
remove_the_file = forms.BooleanField(required=False)
def save(self, *args, **kwargs):
object = super(self.__class__, self).save(*args, **kwargs)
if self.cleaned_data.get('remove_the_file'):
object.the_file = ''
return object
Use that form in your ModelAdmin, and there's no need to change the database.
there is what i created in forms.py:
class MediaForm(forms.ModelForm):
remove_the_file = forms.BooleanField(required=False)
def save(self, *args, **kwargs):
object = super(self.__class__, self).save(*args, **kwargs)
if self.cleaned_data.get('remove_the_file'):
object.the_file = ''
return object
And there is my admin.py:
class MediaAdmin(admin.ModelAdmin):
raw_id_fields = ('parent',)
how should i change MediaAdmin class to apply it?
class MediaAdmin(admin.ModelAdmin):
raw_id_fields = ('parent',)
form = MediaForm