56 lines
1.8 KiB
Python
56 lines
1.8 KiB
Python
from django.conf import settings
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from django.core.files.uploadedfile import UploadedFile
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from django.db import models
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from django.forms import widgets
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from PIL import Image, ImageOps
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def makeThumnail(data: UploadedFile, size: 'tuple[int, int]'):
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with Image.open(data) as img:
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ImageOps.exif_transpose(img, in_place=True)
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img.thumbnail(size)
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if img.mode != 'RGB':
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img = img.convert('RGB')
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data.seek(0)
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data.truncate()
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img.save(data, 'jpeg')
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class ImageFileWidget(widgets.ClearableFileInput):
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template_name = 'forms/img-with-preview.html'
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def get_context(self, name, value, attrs):
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context = super().get_context(name, value, attrs)
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context['MEDIA_URL'] = settings.MEDIA_URL
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return context
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class ThumbnailImageField(models.ImageField):
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__del_image_on_save = False
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def formfield(self, **kwargs):
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kwargs['widget'] = ImageFileWidget
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return super().formfield(**kwargs)
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def save_form_data(self, instance, data):
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if data is False:
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self.__del_image_on_save = True
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if isinstance(data, UploadedFile):
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makeThumnail(data, (800, 600)) # only on create
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# on update: django.db.models.fields.files.ImageFieldFile
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super().save_form_data(instance, data)
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def pre_save(self, model_instance, add):
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if self.__del_image_on_save:
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self.__del_image_on_save = False
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self.deletePreviousImage(model_instance)
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return super().pre_save(model_instance, add)
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def deletePreviousImage(self, instance: models.Model):
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if not instance.pk:
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return
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prev = instance.__class__.objects.get(pk=instance.pk)
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imgField = getattr(prev, self.attname)
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imgField.delete(save=False)
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