Fix lost cropped images scales after content modification

This refs IMIO #14901
This is already fixed in Plone 5 but not in Plone 4
See collective/plone.app.imagecropping#21

CHANGES.rst

@@ -4,6 +4,11 @@ Changelog
 0.8.48 (unreleased)
 -------------------
 
+- Fix lost cropped images scales on a content after a modification : #14901
+  This is already fixed in Plone 5 but not in Plone 4.
+  See https://github.com/collective/plone.app.imagecropping/issues/21
+  [laulaz]
+
 - Fix typo for css class.
   [bsuttor]
 

cpskin/core/configure.zcml

@@ -64,6 +64,10 @@
                    zope.lifecycleevent.interfaces.IObjectModifiedEvent"
               handler=".events.set_lat_lng" />
 
+  <subscriber for="plone.app.imagecropping.interfaces.IImageCroppingMarker
+                   zope.lifecycleevent.interfaces.IObjectModifiedEvent"
+              handler=".events.apply_crops_after_modify" />
+
   <adapter
     for="imio.dashboard.content.pod_template.IDashboardPODTemplate
          plone.app.contenttypes.interfaces.ICollection"

cpskin/core/events.py

@@ -1,4 +1,10 @@
 # -*- coding: utf-8 -*-
+from plone.app.imagecropping import PAI_STORAGE_KEY
+from plone.app.imagecropping.interfaces import IImageCroppingUtils
+from zope.annotation.interfaces import IAnnotations
+from zope.component import getMultiAdapter
+from zope.globalrequest import getRequest
+
 from cpskin.core.utils import get_address_from_obj
 from cpskin.core.utils import has_lat_lng
 from cpskin.core.utils import set_coord
@@ -13,3 +19,25 @@ def set_lat_lng(obj, event):
         return
     request = obj.REQUEST
     set_coord(obj, request)
+
+
+def apply_crops_after_modify(obj, event):
+    """
+    Bug fixed here : cropped images scales on a content are lost after a
+                     modification of this content (#14901).
+    This is already fixed in Plone 5 but not in Plone 4 :
+        https://github.com/collective/plone.app.imagecropping/issues/21
+    To fix this, we need to re-generate all the crops of an object just after
+    it's modification.
+    """
+    crops = IAnnotations(obj).get(PAI_STORAGE_KEY)
+    if not crops:
+        return
+    croputils = IImageCroppingUtils(obj)
+    request = getRequest()
+    cropper = getMultiAdapter((obj, request), name='crop-image')
+    for fieldname in croputils.image_field_names():
+        for crop_key in crops:
+            if crop_key.startswith(fieldname):
+                scalename = crop_key[len(fieldname) + 1:]
+                cropper._crop(fieldname, scalename, crops[crop_key])

setup.py

@@ -67,6 +67,7 @@
           'phonenumbers',
           'collective.contact.facetednav',
           'collective.dexteritytextindexer',
+          'plone.app.imagecropping',
       ],
       extras_require={
           'test': [