Delet file when model deleted and set file save path

src/document/models.py

+import os
+
 from django.db import models
 from django.core import validators
-
+from django.dispatch import receiver
 from account.models import Profile
 from homework.models import Solution
 from common.validators import FileSizeValidator
 
 
+def document_file_name(instance, filename):
+    return '/'.join([
+        'document',
+        instance.solution.task.title,
+        instance.uploaded_by.full_name,
+        filename
+    ])
+
+
 class Document(models.Model):
     uploaded_by = models.ForeignKey(Profile, on_delete=models.DO_NOTHING)
     uploaded_at = models.DateTimeField(auto_now_add=True, editable=False)
@@ -22,9 +33,18 @@ class Document(models.Model):
             FileSizeValidator(size_limit=52428800),  # 52428800 - 50MiB
         ],
         blank=True,
-        null=True
+        null=True,
+        upload_to=document_file_name
     )
     solution = models.ForeignKey(Solution, related_name='files', on_delete=models.CASCADE)
 
     def __str__(self):
         return self.name
+
+
+# Deletes file from filesystem when File object is deleted.
+@receiver(models.signals.post_delete, sender=Document)
+def auto_delete_file_on_delete(sender, instance, **kwargs):
+    if instance.file:
+        if os.path.isfile(instance.file.path):
+            os.remove(instance.file.path)