how can i save images files in Django

Question

1. I want to receive several image groups in one form and save them. I want to save each image group with the same main title and different title. How can I save and target images files on views.py?

2. I didn't hand over the form to the request from views.py because the user could add and delete the content. Is there a way to use a form tag when I want to receive data that I don't know how many?

views.py

def debate_create(request):
    if request.method == "POST":
        content = request.POST.items()
        for k,v in content:
            if k == 'sup_title':
                sup_title = SuperTitle()
                sup_title.author = request.user
                sup_title.super_title = v
                sup_title.save()
                sup_title_id = sup_title.id
            elif 'img' not in k and 'opt' not in k and 'section' in k:
                sub_title = Subtitle()
                sub_title.super_title = get_object_or_404(SuperTitle, pk = sup_title_id)
                sub_title.sub_title = v
                sub_title.save()
            elif 'img' in k and v != '':
                stg = Images()
                # imgs = request.FILES.getlist("?????")
                # for image in imgs
                stg.sub_title = get_object_or_404(Subtitle, pk = sub_title.id)
                stg.save()
            elif 'section' in k and 'opt' in k:
                opt = SelectOption()
                opt.sub_title = get_object_or_404(Subtitle, pk = sub_title.id)
                opt.option = v
                opt.save()
        return render(request, 'polls/test.html')
    else:
        pass

html

<form method="POST" id="debate_form" action="{% url 'polls:debate_create' %}">
        {% csrf_token %}
        <input type='text' name='sup_title' placeholder='제목'>
        <div id="form_container">
            <section id='section_1'>
                <input type="text" name="section_1">
                <input type="file" name="img_section_1" multiple>
                <div id="section_1_div">
                    <input type="text" name="section_1_opt_1" value="찬성">
                    <input type="text" name="section_1_opt_2" value="반대">
                </div>
                <input type="button" value="선택지 추가하기" onclick='add_option(this.id)' id="section_1">
                <input type="button" value="선택지 삭제하기" onclick='sub_option(this.id)' id="section_1">
            </section>
        </div>
        <input type="button" value='질문 추가하기' onclick='add_content()'>
        <input type="button" value='질문 삭제하기' onclick='sub_content()'>
        <input type="submit">
    </form>

Answer 1

There is of course a way to achieve this in Django, and it is called model formsets.

Suppose your models are defined as such

# models.py
from django.db import models

class SuperTitle(models.Model):
    super_title = models.CharField(max_length=50)
    author = models.ForeignKey(User, on_delete=models.PROTECT)

class Subtitle(models.Model):
    super_title = models.ForeignKey(SuperGroup, on_delete=models.CASCADE)
    subtitle = models.CharField(max_length=50)
    image = models.ImageField(upload_to='path/to/uploads/')
    # I changed opt from a model to a field of Subtitle, 
    # since it has only 2 values in your example.
    # Feel free to change it back. 
    opt = models.IntegerField(choices=[(1,"찬성"), (2, "반대")])

Then in your views

# views.py
from django import forms
from .models import SuperTitle, Subtitle

def debate_create(request):
    SuperTitleForm = forms.modelform_factory(SuperTitle, fields=['super_title'])
    SubtitleFormSet = forms.modelformset_factory(Subtitle, fields=['subtitle', 'image', 'opt'])
    if request.method == 'POST':
        super_title_form = SuperTitleForm(request.POST)
        # NOTE uploaded files are available in request.FILES
        subtitle_formset = SubtitleFormSet(request.POST, request.FILES, queryset=Subtitle.objects.none())
        if super_title_form.is_valid() and subtitle_formset.is_valid():
            super_title = super_title_form.save()
            subtitles = subtitle_forms.save(commit=False)
            for subtitle in subtitles:
                subtitle.super_title = super_title
            Subtitle.objects.bulk_create(subtitles)
    else:
        super_title_form = SuperTitleForm()
        subtitle_formset = SubtitleFormSet(queryset=Subtitle.objects.filter(super_title__author=request.user))
    context = {
        'super_title_form': super_title_form,
        'subtitle_formset': subtitle_formset,
    }
    return render(request, 'polls/test.html', context)

Please note that I pass queryset=Subtitle.objects.none() to formset. This will make formset only deal with new subtitles. If you want to edit or even delete existing subtitles, change the queryset to, for example, queryset=Subtitle.objects.filter(super_title__author=request.user). Django recommends the queryset being ordered.

And you probably need to do similar thing to super_title_form so that it knows which super_title your are editing.

Please also note that there are two required hidden field when rendering formset manually:

{{ subtitle_formset.management_form.TOTAL_FORMS }}
{{ subtitle_formset.management_form.INITIAL_FORMS }}

Personally, I like to put these 2 alongside {% csrf_token %}, in case not forgetting them.

Edited: one more thing for your 1st question

You can customize your image store path like following

def subtitle_image_path(instance, filename):
    return f'uploads/{instance.super_title.id}/{filename}'
class Subtitle(models.Model):
    ..
    image = models.ImageField(upload_to=subtitle_image_path)

and django will automatically save the image to, say, uploads/1/img01.png when you call form.save() (or subtitle.save() in this case).