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How to Update ImageField in Django?

i am new in Django. i am having issue in updating ImageField.i have following code
in models.py
class ImageModel(models.Model):
image_name = models.CharField(max_length=50)
image_color = models.CharField(max_length=50)
image_document = models.ImageField(upload_to='product/')
-This is My forms.py
class ImageForm(forms.ModelForm):
class Meta:
model = ImageModel
fields = ['image_name', 'image_color' , 'image_document']
in Html file (editproduct.html)
<form method="POST" action="/myapp/updateimage/{{ singleimagedata.id }}">
{% csrf_token %}
<input class="form-control" type="text" name="image_name" value="{{ singleimagedata.image_name}}">
<input class="form-control" type="file" name="image_document">
<button type="submit" class="btn btn-primary">UPDATE PRODUCT</button>
</form>
-myapp is my application name. {{singleimagedata}} is a Variable Containing all fetched Data
-urls.py
urlpatterns = [
path('productlist', views.productlist, name='productlist'),
path('addproduct', views.addproduct, name='addproduct'),
path('editimage/<int:id>', views.editimage, name='editimage'),
path('updateimage/<int:id>', views.updateimage, name='updateimage'),
]
and Here is My views.py
def productlist(request):
if request.method == 'GET':
imagedata = ImageModel.objects.all()
return render(request,"product/productlist.html",{'imagedata':imagedata})
def addproduct(request):
if request.method == 'POST':
form = ImageForm(request.POST, request.FILES)
if form.is_valid():
form.save()
messages.add_message(request, messages.SUCCESS, 'Image Uploaded')
return redirect('/myapp/productlist')
else:
imageform = ImageForm()
return render(request, "product/addproduct.html", {'imageform': imageform})
def editimage(request, id):
singleimagedata = ImageModel.objects.get(id=id)
return render(request, 'product/editproduct.html', {'singleimagedata': singleimagedata})
def updateimage(request, id): #this function is called when update data
data = ImageModel.objects.get(id=id)
form = ImageForm(request.POST,request.FILES,instance = data)
if form.is_valid():
form.save()
return redirect("/myapp/productlist")
else:
return render(request, 'demo/editproduct.html', {'singleimagedata': data})
My image Upload is working fine.i can not Update image while updating data.rest of the data are updated.i don't know how to update image and how to remove old image and put new image into directory.

I think you missed the enctype="multipart/form-data", try to change:
<form method="POST" action="/myapp/updateimage/{{ singleimagedata.id }}">
into;
<form method="POST" enctype="multipart/form-data" action="{% url 'updateimage' id=singleimagedata.id %}">
Don't miss also to add the image_color field to your html input.
Because, in your case the image_color field model is designed as required field.
To remove & update the old image file from directory;
import os
from django.conf import settings
# your imported module...
def updateimage(request, id): #this function is called when update data
old_image = ImageModel.objects.get(id=id)
form = ImageForm(request.POST, request.FILES, instance=old_image)
if form.is_valid():
# deleting old uploaded image.
image_path = old_image.image_document.path
if os.path.exists(image_path):
os.remove(image_path)
# the `form.save` will also update your newest image & path.
form.save()
return redirect("/myapp/productlist")
else:
context = {'singleimagedata': old_image, 'form': form}
return render(request, 'demo/editproduct.html', context)

I had a similar issue while updating the profile_pic of user. I solved this with the following code I think this might help:
Models.py
class Profile(models.Model):
# setting o2o field of user with User model
user_name = models.OneToOneField(User, on_delete=models.CASCADE, blank=True, null=True)
first_name = models.CharField(max_length=70, null=True, blank=True)
last_name = models.CharField(max_length=70, null=True, blank=True)
profile_pic = models.ImageField(upload_to="images", blank=True, null=True,)
def __str__(self):
return str(self.user_name)
forms.py
class ProfileEditForm(ModelForm):
class Meta:
model = Profile
fields = '__all__'
# excluding user_name as it is a one_to_one relationship with User model
exclude = ['user_name']
views.py
#login_required(login_url='login')
def edit_profile(request, id):
username = get_object_or_404(Profile, id=id)
extended_pro_edit_form = ProfileEditForm(instance=username)
if request.method == "POST":
extended_pro_edit_form = ProfileEditForm(request.POST, request.FILES, instance=username)
if extended_pro_edit_form.is_valid():
extended_pro_edit_form.save()
next_ = request.POST.get('next', '/')
return HttpResponseRedirect(next_)
context = {'extended_pro_edit_form': extended_pro_edit_form}
return render(request, 'edit_profile.html', context)
edit-profile.html
<form action="" method="post"
enctype="multipart/form-data">
{% csrf_token %}
{{ extended_pro_edit_form.as_p }}
{{ extended_pro_edit_form.errors }}
<!--To redirect user to prvious page after post req-->
<input type="hidden" name="next" value="{{ request.GET.next }}">
<button type="submit">UPDATE</button>
</form>

Answer from #binpy should solve your problem. In addition to your second answer, you could do:
def updateimage(request, id): #this function is called when update data
data = ImageModel.objects.get(id=id)
form = ImageForm(request.POST,request.FILES,instance = data)
if form.is_valid():
data.image_document.delete() # This will delete your old image
form.save()
return redirect("/myapp/productlist")
else:
return render(request, 'demo/editproduct.html', {'singleimagedata': data})
Check delete() method on django docs.

some times something like cached old image is not replaced in the front-end so you might just need to forces refresh by pressing CTRL + F5 or clear your browsing history.
the answer given by #binpy is a needed update so that the files are passed to the back-end.

Retrieve variable from instance of Django form

I have a Django form NameForm. I am attempting to iterate over an array of values and, for each value, have an option to display the same form. The only thing that should change with the form submission should be the associated value to which the form is displayed next to.
This becomes much clearer with an example. For some array [1,2,3] we should display:
We can then click on any open form icon, fill out the NameForm form. The resultant information, including the form_id (in this case 1, 2, or 3) should be returned to forms.py. How can I fetch the form_id variable from an instance of NameForm in index.py?
My (hacky) attempt can be found below. The problem is I don't know how to access the form_id variable I created in the NameForm object.
forms.py
class NameForm(forms.Form):
form_id = None
your_name = forms.CharField(label='Your name', max_length=3)
views.py
def index(request):
if request.method == 'POST':
form = NameForm(request.POST)
form_id = form.form_id # The problem line, as form_id is always None
if form.is_valid():
return HttpResponse( \
' '.join((str(form.cleaned_data['your_name']),form_id ))\
) #Throws TypeError as can't join None and string
else:
forms = []
vals = [1,2,3]
for val in vals:
form = NameForm()
form.form_id = val
forms.append(form)
return render(request, 'post/index.html', {'forms': forms})
index.html
{%for form in forms%}
{{form.form_id}}
<button class="button" onclick="openForm()">Open Form</button>
<div class="myForm">
<form class="form-container" method="post">
{% csrf_token %}
{{ form }}
<input type="submit" value="Submit">
<button class="button" onclick="closeForm()">Cancel</button>
</form>
</div>
</br>
{%endfor%}

In Django Form or Django Model, when you set a field's value to None, it is assumed that you want to ignore said field. This is helpful when creating a model that inherits from another model and you want to remove some unnecessary fields.
If you want to set value for a field on Form creation, you should pass it into __init__ method. E.g:
class NameForm(forms.Form):
form_id = forms.IntegerField(widget=forms.HiddenInput())
your_name = forms.CharField(label='Your name', max_length=3)
def __init__(self, form_id, *args, **kwargs):
self.fields['form_id'].initial = form_id
Alternatively, instead of overriding the __init__ method, you can set an initial value for form_id when you create an instance of NameForm. For example:
vals = [1,2,3]
forms = [NameForm(initial={'form_id': val}) for val in vals]

Django image form isn't saving the image

I have a form that involves uploading a profile picture. I have it working so that I can upload images in the /admin/ interface and display them correctly, but I cannot get my Modelform to save the image.
Here is what I have:
models.py
class Candidate(models.Model):
UserID = models.ForeignKey(User, on_delete=models.CASCADE)
ElectionID = models.ForeignKey(Election, on_delete=models.CASCADE)
Bio = models.CharField(max_length=500, blank=True)
ProfilePicture = models.ImageField(upload_to="profilepics/", null=True, blank=True)
forms.py
class AddCandidateForm(forms.ModelForm):
class Meta:
model = Candidate
fields = ['ElectionID', 'Bio', 'ProfilePicture']
cand_reg.html (Template)
{% block content %}
<h1>Register as a candidate</h1>
<form method="POST" class="post-form">
{% csrf_token %}
<h2>Select an election:</h2><br>
{{form.ElectionID}}<br>
<h2>Enter your bio:</h2><br>
{{form.Bio}}<br>
<h2>Upload a profile picture:</h2><br>
{{form.ProfilePicture}}<br>
<button type="submit">Register</button>
</form>
{% endblock %}
When I try the view function like so I get the error:
MultiValueDictKeyError at /register/
"'ProfilePicture'"
views.py
def add_candidate(request):
if request.method == 'POST':
form = AddCandidateForm(request.POST, request.FILES)
if form.is_valid():
candidate = form.save(commit=False)
candidate = request.FILES['ProfilePicture']
candidate.UserID = request.user
candidate.save()
return redirect('/home/')
else:
form = AddCandidateForm()
return render(request, 'cand_reg.html', {
"form": form
})
views.py
When I remove the offending line, the error goes away.
def add_candidate(request):
if request.method == 'POST':
form = AddCandidateForm(request.POST, request.FILES)
if form.is_valid():
candidate = form.save(commit=False)
# candidate = request.FILES['ProfilePicture']
candidate.UserID = request.user
candidate.save()
return redirect('/home/')
else:
form = AddCandidateForm()
return render(request, 'cand_reg.html', {
"form": form
})
However, this doesn't actually save the image, so when I try to render it in a separate template, I get an error then.
Can anyone help me understand why the image isn't uploading?
Thanks in advance :)

You must set the ProfilePicture attribute of the model and not the instance itself (candidate = request.FILES['ProfilePicture']).
Change to:
candidate = form.save(commit=False)
candidate.ProfilePicture = request.FILES['ProfilePicture']
candidate.UserID = request.user
candidate.save()
Change your HTML form to accept files as well. Change to: <form method="POST" enctype="multipart/form-data" class="post-form">. When a form includes file inputs (<input type="file" />), then it must be encoded differently than it used when it includes only text. More here. If you right-click and inspect the {{form.ProfilePicture}} you'll see that this is actually a file input.
Extra one:
Please, do not name your class attributes (ProfilePicture, UserID etc) in PascalCase. Use snake_case instead (profile_picture, user_id etc).

Passing query string to ModelForm hidden field - Django

I want to pass a query string e.g., ?refcode='A1234' to a hidden field called inbound_referral_code in a ModelForm.
My model is as follows:
class User(models.Model):
email = models.EmailField(max_length=255, blank=False, unique=True)
inbound_referral_code = models.CharField(max_length=255)
My ModelForm is currently as follows:
class UserForm(forms.ModelForm):
model = User
fields = ['email', 'inbound_referral_code']
widgets = {'inbound_referral_code': forms.HiddenInput()}
My View is:
def register(request):
if request.method == 'POST':
form = UserForm(request.POST)
[...]
else:
form = UserForm()
return render(request, 'register.html', {'form': form})
And my template is currently:
<form action="{% url 'register' %}" method="post">
{% csrf_token %}
{{ form.as_p }}
<input type="submit" value="Submit"/>
</form>
Two questions:
How do I assign ?refcode parameter to inbound_referral_code field?
What happens if ?refcode isn't provided?

Combining the different answers, the following solution worked:
Set the "initial" value of the form parameter, and ensure the template renders with the bound form if validation fails. The correct view function is:
def register(request):
if request.method == 'POST':
form = UserForm(request.POST)
if form.is_valid():
return redirect([...])
else:
refcode = request.GET.get('refcode')
form = UserForm(intial={'inbound_referral_code': refcode)
return render(request, 'register.html', {'form': form})
Note that the bottom return render(...) needed to be moved so that it is also called with the form from the POST request if it contains validation errors...

To assign the refcode, you need to pass it into the form, so you pass in something other than request.POST that contains it, change it before
dict = request.POST.copy()
dict["inbound_referral_code"] = request.POST.get("refcode")
form = UserForm(dict)
# ...
or after validating:
if form.is_valid():
form.cleaned_data["inbound_referral_code"] = request.POST.get("refcode")
If it isn't provided, you can check for that and pass a custom value, or set a default when defining the form/model.
To set it in the template, you can pass an initial value
else:
form = UserForm(initial={"inbound_referral_code": "ref-value-here"})
return render(request, 'register.html', {'form': form})

Django: two forms in one view

How would I write a view with a single form to add a new person, and on that same form, be able to add 0 or 1 or 2 or ... 68757857 images of that same person?
Please refer to the code below.
In models.py:
class Person(models.Model):
name = models.CharField(max_length=50)
class Image(models.Model):
person = models.ForeignKey(Person)
image = models.ImageField(upload_to='images/')
In forms.py:
class PersonForm(forms.ModelForm):
class Meta:
model = Product
fields = ['name']
class ImageForm(forms.ModelForm):
class Meta:
model = Image
fields = ['person', 'image']
From what I have seen, formsets are used. I have looked at many examples on SO, read the documentation and I am still confused.
I would appreciate it if someone can provide an example of a views.py that fulfils the specification at the beginning of this question.

You could use Inline formsets.
In view.py firt of all you have to create a new person instance and then use this instance with formset:
from django.forms import inlineformset_factory
ImageFormSet = inlineformset_factory(Person, Image, fields=('image',))
def my_view(request):
form = PersonForm(request.POST or None)
if form.is_valid():
new_person = form.save()
formset = ImageFormSet(request.POST or None, request.FILES or None, instance=new_person)
if formset.is_valid():
formset.save()
return redirect('persons:main')
else:
formset = ImageFormSet(request.POST or None, request.FILES or None)
return render(request, 'my_template.html', {'formset': formset, 'form': form})
In my_template.html:
<form action="" method="post" enctype="multipart/form-data">
{{ form.as_p }}
{{ formset.management_form }}
{% for frm in formset %}
{{ frm.as_p }}
{% endfor %}
<input type="submit" value="Create">
</form>