misc: caching for thumbnails (#52528)

tests/test_upload_storage.py

@@ -1,10 +1,12 @@
 # -*- coding: utf-8 -*-
 
+import hashlib
 import json
 import os
 
 import mock
 import pytest
+from django.utils.encoding import force_bytes
 from webtest import Upload
 
 from wcs import fields
@@ -241,6 +243,41 @@ def test_form_file_field_upload_storage(wscall, pub):
     }
 
 
+def test_thumbnail_caching(pub):
+    create_user_and_admin(pub)
+    FormDef.wipe()
+    formdef = FormDef()
+    formdef.name = 'test'
+    formdef.fields = [
+        fields.FileField(id='0', label='file', varname='file'),
+    ]
+    formdef.store()
+
+    assert formdef.fields[0].storage == 'default'
+
+    image_content = open(os.path.join(os.path.dirname(__file__), 'image-with-gps-data.jpeg'), 'rb').read()
+    upload = Upload('file.jpg', image_content, 'image/jpeg')
+
+    resp = get_app(pub).get('/test/')
+    resp.forms[0]['f0$file'] = upload
+    resp = resp.forms[0].submit('submit')
+    assert 'Check values then click submit.' in resp.text
+    resp = resp.forms[0].submit('submit')
+    assert resp.status_int == 302
+    resp = resp.follow()
+    assert 'The form has been recorded' in resp.text
+
+    data_file = formdef.data_class().get(1).data['0']
+    thumbs_dir = os.path.join(pub.app_dir, 'thumbs')
+    thumb_filepath = os.path.join(
+        thumbs_dir, hashlib.sha256(force_bytes(data_file.get_fs_filename())).hexdigest()
+    )
+    assert os.path.exists(thumb_filepath) is False
+    admin_app = login(get_app(pub), username='admin', password='admin')
+    admin_app.get('/backoffice/management/test/1/download?f=0&thumbnail=1').follow()
+    assert os.path.exists(thumb_filepath) is True
+
+
 @mock.patch('wcs.wscalls.call_webservice')
 def test_remoteopaque_in_attachmentevolutionpart(wscall, pub):
     create_user_and_admin(pub)

wcs/qommon/misc.py

@@ -40,7 +40,7 @@ except ImportError:
 from django.conf import settings
 from django.template import TemplateSyntaxError, VariableDoesNotExist
 from django.utils import datetime_safe
-from django.utils.encoding import force_text
+from django.utils.encoding import force_bytes, force_text
 from django.utils.formats import localize
 from django.utils.html import strip_tags
 from django.utils.text import Truncator
@@ -655,6 +655,16 @@ def get_thumbnail(filepath, content_type=None):
     if not can_thumbnail(content_type or ''):
         raise ThumbnailError()
 
+    # check if thumbnail already exists
+    thumbs_dir = os.path.join(get_publisher().app_dir, 'thumbs')
+    if not os.path.exists(thumbs_dir):
+        os.mkdir(thumbs_dir)
+    thumb_filepath = os.path.join(thumbs_dir, hashlib.sha256(force_bytes(filepath)).hexdigest())
+    if os.path.exists(thumb_filepath):
+        with open(thumb_filepath, 'rb') as f:
+            return f.read()
+
+    # generate thumbnail
     if content_type == 'application/pdf':
         try:
             fp = io.BytesIO(
@@ -705,6 +715,11 @@ def get_thumbnail(filepath, content_type=None):
     except IOError:
         # failed to create thumbnail.
         raise ThumbnailError()
+
+    # store thumbnail
+    with open(thumb_filepath, 'wb') as f:
+        f.write(image_thumb_fp.getvalue())
+
     return image_thumb_fp.getvalue()