Deduplicated file hash calculation method

boards/models/attachment/__init__.py

@@ -5,6 +5,7 b' import time'
 from random import random
 
 from django.db import models
+from boards import utils
 
 from boards.models.attachment.viewers import get_viewers, AbstractViewer
 
@@ -15,26 +16,17 b" FILE_EXTENSION_DELIMITER = '.'"
 
 class AttachmentManager(models.Manager):
     def create_with_hash(self, file):
-        file_hash = self.get_hash(file)
+        file_hash = utils.get_file_hash(file)
         existing = self.filter(hash=file_hash)
         if len(existing) > 0:
             attachment = existing[0]
         else:
             file_type = file.name.split(FILE_EXTENSION_DELIMITER)[-1].lower()
-            attachment = Attachment.objects.create(file=file,
-                    mimetype=file_type, hash=file_hash)
+            attachment = Attachment.objects.create(
+                file=file, mimetype=file_type, hash=file_hash)
 
         return attachment
 
-    def get_hash(self, file):
-        """
-        Gets hash of an file.
-        """
-        md5 = hashlib.md5()
-        for chunk in file.chunks():
-            md5.update(chunk)
-        return md5.hexdigest()
-
 
 class Attachment(models.Model):
     objects = AttachmentManager()

boards/models/image.py

@@ -6,7 +6,7 b' import time'
 from django.db import models
 from django.template.defaultfilters import filesizeformat
 
-from boards import thumbs
+from boards import thumbs, utils
 import boards
 from boards.models.base import Viewable
 
@@ -24,7 +24,7 b" CSS_CLASS_THUMB = 'thumb'"
 
 class PostImageManager(models.Manager):
     def create_with_hash(self, image):
-        image_hash = self.get_hash(image)
+        image_hash = utils.get_file_hash(image)
         existing = self.filter(hash=image_hash)
         if len(existing) > 0:
             post_image = existing[0]
@@ -33,15 +33,6 b' class PostImageManager(models.Manager):'
 
         return post_image
 
-    def get_hash(self, image):
-        """
-        Gets hash of an image.
-        """
-        md5 = hashlib.md5()
-        for chunk in image.chunks():
-            md5.update(chunk)
-        return md5.hexdigest()
-
     def get_random_images(self, count, include_archived=False, tags=None):
         images = self.filter(post_images__thread__archived=include_archived)
         if tags is not None:
@@ -89,7 +80,7 b' class PostImage(models.Model, Viewable):'
         """
 
         if not self.pk and self.image:
-            self.hash = PostImage.objects.get_hash(self.image)
+            self.hash = utils.get_file_hash(self.image)
         super(PostImage, self).save(*args, **kwargs)
 
     def __str__(self):

boards/utils.py

@@ -1,6 +1,7 b''
 """
 This module contains helper functions and helper classes.
 """
+import hashlib
 import time
 import hmac
 
@@ -81,4 +82,11 b' def is_moderator(request):'
     except AttributeError:
         moderate = False
 
-    return moderate
  No newline at end of file
+    return moderate
+
+
+def get_file_hash(file) -> str:
+    md5 = hashlib.md5()
+    for chunk in file.chunks():
+        md5.update(chunk)
+    return md5.hexdigest()