73 lines
3.3 KiB
Python
73 lines
3.3 KiB
Python
from django.core.files.base import ContentFile
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from django.db import models, IntegrityError
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from django_softdelete.models import SoftDeleteModel
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from inventory.models import Item
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def hash_upload(instance, filename):
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return f"{instance.hash[:2]}/{instance.hash[2:4]}/{instance.hash[4:6]}/{instance.hash[6:]}"
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class FileManager(models.Manager):
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def get_or_create(self, **kwargs):
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if 'data' in kwargs and type(kwargs['data']) == str:
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import base64
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from hashlib import sha256
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raw = kwargs['data']
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if not raw.startswith('data:'):
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raise ValueError('data must be a base64 encoded string or file and hash must be provided')
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raw = raw.split(';base64,')
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if len(raw) != 2:
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raise ValueError('data must be a base64 encoded string or file and hash must be provided')
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mime_type = raw[0].split(':')[1]
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content = base64.b64decode(raw[1], validate=True)
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kwargs.pop('data')
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content_hash = sha256(content).hexdigest()
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kwargs['file'] = ContentFile(content, content_hash)
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kwargs['hash'] = content_hash
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kwargs['mime_type'] = mime_type
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else:
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raise ValueError('data must be a base64 encoded string or file and hash must be provided')
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try:
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return self.get(hash=kwargs['hash']), False
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except self.model.DoesNotExist:
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return self.create(**kwargs), True
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def create(self, **kwargs):
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if 'data' in kwargs and type(kwargs['data']) == str:
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import base64
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from hashlib import sha256
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raw = kwargs['data']
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if not raw.startswith('data:'):
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raise ValueError('data must be a base64 encoded string or file and hash must be provided')
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raw = raw.split(';base64,')
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if len(raw) != 2:
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raise ValueError('data must be a base64 encoded string or file and hash must be provided')
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mime_type = raw[0].split(':')[1]
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content = base64.b64decode(raw[1], validate=True)
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kwargs.pop('data')
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content_hash = sha256(content).hexdigest()
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kwargs['file'] = ContentFile(content, content_hash)
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kwargs['hash'] = content_hash
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kwargs['mime_type'] = mime_type
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elif 'file' in kwargs and 'hash' in kwargs and type(kwargs['file']) == ContentFile:
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pass
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else:
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raise ValueError('data must be a base64 encoded string or file and hash must be provided')
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if not self.filter(hash=kwargs['hash']).exists():
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return super().create(**kwargs)
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else:
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raise IntegrityError('File with this hash already exists')
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class File(models.Model):
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item = models.ForeignKey(Item, models.CASCADE, db_column='iid', null=True, blank=True, related_name='files')
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created_at = models.DateTimeField(blank=True, null=True)
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updated_at = models.DateTimeField(blank=True, null=True)
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deleted_at = models.DateTimeField(blank=True, null=True)
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file = models.ImageField(upload_to=hash_upload)
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mime_type = models.CharField(max_length=255, null=False, blank=False)
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hash = models.CharField(max_length=64, null=False, blank=False, unique=True)
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objects = FileManager()
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