Crop image at center on backend

apps/user/views.py

@@ -1,3 +1,6 @@
+from io import BytesIO
+from PIL import Image
+from os.path import splitext
 from django.contrib.auth import login
 from django.shortcuts import render, reverse
 from django.views.generic import DetailView, UpdateView
@@ -42,6 +45,30 @@ class UserEditView(UpdateView):
 
     def post(self, request, *args, **kwargs):
         # it's magic *-*-*-*-*
+        if 'photo' in request.FILES:
+            photo_fp = request.FILES.pop('photo')[0]
+            fname = photo_fp.name
+            photo = Image.open(photo_fp)
+            lowest_side = min(photo.size)
+            horizontal_padding = (lowest_side - photo.size[0]) / 2
+            vertical_padding = (lowest_side - photo.size[1]) / 2
+            photo = photo.crop(
+                (
+                    -horizontal_padding,
+                    -vertical_padding,
+                    photo.size[0] + horizontal_padding,
+                    photo.size[1] + vertical_padding
+                )
+            )
+            if photo.size[0] > 512:
+                photo = photo.resize((512, 512,))
+            buffer = BytesIO()
+            ext = splitext(fname)[1][1:].upper()
+            if ext == 'JPG':
+                ext = 'JPEG'
+            photo.save(buffer, ext)
+            self.object.photo.save(fname, buffer)
+            buffer.close()
         if not request.POST._mutable:
             request.POST._mutable = True
         old_password = request.POST.pop('old_password')[0]