Resize File

#format_checker.py

from django.db.models import FileField
from django.forms import forms
from django.template.defaultfilters import filesizeformat
from django.utils.translation import ugettext_lazy as _


class ContentTypeRestrictedFileField(FileField):

    """
        Same as FileField, but you can specify:
        * content_types - list containing allowed content_types. Example: ['application/pdf', 'image/jpeg']
        * max_upload_size - a number indicating the maximum file size allowed for upload.
        2.5MB - 2621440
        5MB - 5242880
        10MB - 10485760
        20MB - 20971520
        50MB - 5242880
        100MB 104857600
        250MB - 214958080
        500MB - 429916160
    """

    def __init__(self, *args, **kwargs):

        self.content_types = kwargs.pop("content_types", None)
        self.max_upload_size = kwargs.pop("max_upload_size", "2621440")

        super(ContentTypeRestrictedFileField, self).__init__(*args, **kwargs)


    def clean(self, *args, **kwargs):
        data = super(ContentTypeRestrictedFileField, self).clean(*args, **kwargs)

        file = data.file
        try:
            content_type = file.content_type
            if content_type in self.content_types:
                if file._size > self.max_upload_size:
                    raise forms.ValidationError(_('Please keep filesize under %s. Current filesize %s') % (
                        filesizeformat(self.max_upload_size), filesizeformat(file._size)))
                else:
                    raise forms.ValidationError(_('Filetype not supported.'))
        except AttributeError:
            pass

        return data



#models.py

from PIL import Image

class Menu(models.Model):

    name = models.CharField(max_length=100)
    price = models.IntegerField()
    image = ContentTypeRestrictedFileField(
        upload_to='menu/image/',
        content_types=[[
            'image/jpeg',
            'image/jpg',
            'image/png'
            ]
        ],
        max_upload_size=2621440,
        blank=True,
        null=True,
        help_text="Max size is 2.5MB"
        )
    note = models.TextField(blank=True)

    objects = models.Manager()

    def __str__(self):
        return '{0}: {1}'.format(self.kelurahan.name, self.name)


    def save(self, *args, **kwargs):
        image = Image.open(self.image)

        image_ext = os.path.splitext(self.image.path)[1][1:]


        image = image.resize((240, 480), Image.ANTIALIAS)
        self.image = image

        super(Menu, self).save(*args, **kwargs)