How to filter a queryset with another queryset to get a single value from a list of value in the for-CodePudding

I'm currently working on a functionality in my web app, There is a form for users to upload images and when there's more than one images, i'm looping through the images to save each to the db.

The Property Model:

class PostProperty(models.Model):
    poster = models.ForeignKey(User, on_delete=models.CASCADE)
    publish = models.BooleanField(default=False)
    title = models.CharField(max_length=300)
    category = models.CharField(choices=CategoryTypes.choices, default= CategoryTypes.FOR_RENT, max_length=50)
    category_type = models.ForeignKey(PropertyTypes,on_delete=models.CASCADE)

Then i have another model which is linked to the property model which allows users to upload images for the property on another page:

class PostPictures(models.Model):
    post = models.ForeignKey(PostProperty, on_delete=models.CASCADE)
    pictures = models.ImageField(default='property_post.jpg', upload_to='images/')

Have created a view function, which gets the images from the form and compresses it, after compression, it loops through each and saves it to the db.

                    memory_upload = []
                    for x in range(len(images)):
                       img = images[x]
                       im = Image.open(img)
                       im_io = BytesIO()
                       if im.mode != 'RGB':
                          im = im.convert('RGB')
                       im = im.resize(img_res)
                       im.save(im_io, format= 'JPEG', optimize=True, quality=50)
                       memory_upload.append(InMemoryUploadedFile(im_io, None, img.name, 'image/jpeg', im_io.tell(), None ))

                    for items in memory_upload:
                       parser = PostPictures.objects.create(post = property, pictures = items)
                    parser.save()
                    return redirect('profile')

After the images are saved in the db. I want to create a view for the property list where the user can see all the properties they've posted with only a single image being returned out of the list of images for the property, how do i go about it?.

CodePudding user response：

I think have figured it out but might not be the best implementation, if you have a better implementation for it, i would appreciate your answer.

lister = PostProperty.objects.filter(poster = request.user)
pix = []
    for items in lister:
        pics = PostPictures.objects.filter(post__title = items) 
        pix.append(pics[0])

context = {
        'lister':lister,
        'pix':pix, 
        }

This pushes the first value of the iteration and it also carries the properties of the linked model with it

CodePudding user response：

Try this, you can directly query this

PostPictures.objects.filter(post__poster=request.user)