Fixed #264. Now it is possible to delete files/images in MongoEngine backend....

Fixed #264. Now it is possible to delete files/images in MongoEngine backend. Also improved Save and Continue

flask_admin/contrib/mongoengine/fields.py

 from flask import request
 from wtforms import fields
+from wtforms.fields.core import _unset_value
 
 from . import widgets
 
@@ -25,9 +26,27 @@ class ModelFormField(fields.FormField):
 class MongoFileField(fields.FileField):
     widget = widgets.MongoFileInput()
 
+    def __init__(self, label=None, validators=None, **kwargs):
+        super(MongoFileField, self).__init__(label, validators, **kwargs)
+
+        self.should_delete = False
+
+    def process(self, formdata, data=_unset_value):
+        if formdata:
+            marker = '_%s-delete' % self.name
+            if marker in formdata:
+                self.should_delete = True
+
+        return super(MongoFileField, self).process(formdata, data)
+
     def populate_obj(self, obj, name):
         field = getattr(obj, name, None)
         if field is not None:
+            # If field should be deleted, clean it up
+            if self.should_delete:
+                field.delete()
+                return
+
             data = request.files.get(self.name)
 
             if data:

flask_admin/contrib/mongoengine/typefmt.py

@@ -10,6 +10,9 @@ from . import helpers
 
 
 def grid_formatter(view, value):
+    if not value.grid_id:
+        return ''
+
     args = helpers.make_gridfs_args(value)
 
     return Markup(
@@ -25,6 +28,9 @@ def grid_formatter(view, value):
 
 
 def grid_image_formatter(view, value):
+    if not value.grid_id:
+        return ''
+
     return Markup(
         ('<div class="image-thumbnail">' +
             '<a href="%(url)s" target="_blank"><img src="%(thumb)s"/></a>' +

flask_admin/contrib/mongoengine/view.py

@@ -343,7 +343,13 @@ class ModelView(BaseModelView):
             :param id:
                 Model ID
         """
-        return self.get_query().filter(pk=id).first()
+        try:
+            return self.get_query().filter(pk=id).first()
+        except mongoengine.ValidationError as ex:
+            flash(gettext('Failed to get model. %(error)s',
+                          error=format_error(ex)),
+                  'error')
+            return None
 
     def create_model(self, form):
         """

flask_admin/contrib/mongoengine/widgets.py

@@ -12,7 +12,10 @@ class MongoFileInput(object):
     """
         Renders a file input chooser field.
     """
-    template = '<div><i class="icon-file"></i>%(name)s %(size)dk (%(content_type)s)</div>'
+    template = ('<div>'
+                ' <i class="icon-file"></i>%(name)s %(size)dk (%(content_type)s)'
+                ' <input type="checkbox" name="%(marker)s">Delete</input>'
+                '</div>')
 
     def __call__(self, field, **kwargs):
         kwargs.setdefault('id', field.id)
@@ -24,7 +27,8 @@ class MongoFileInput(object):
             placeholder = self.template % {
                 'name': escape(data.name),
                 'content_type': escape(data.content_type),
-                'size': data.length // 1024
+                'size': data.length // 1024,
+                'marker': '_%s-delete' % field.name
             }
 
         return HTMLString('%s<input %s>' % (placeholder,
@@ -37,7 +41,10 @@ class MongoImageInput(object):
     """
         Renders a file input chooser field.
     """
-    template = '<div class="image-thumbnail"><img src="%(thumb)s"/></div>'
+    template = ('<div class="image-thumbnail">'
+                ' <img src="%(thumb)s"/>'
+                ' <input type="checkbox" name="%(marker)s">Delete</input>'
+                '</div>')
 
     def __call__(self, field, **kwargs):
         kwargs.setdefault('id', field.id)
@@ -46,7 +53,8 @@ class MongoImageInput(object):
         if field.data and isinstance(field.data, ImageGridFsProxy):
             args = helpers.make_thumb_args(field.data)
             placeholder = self.template % {
-                'thumb': url_for('.api_file_view', **args)
+                'thumb': url_for('.api_file_view', **args),
+                'marker': '_%s-delete' % field.name
             }
 
         return HTMLString('%s<input %s>' % (placeholder,

flask_admin/model/base.py

@@ -1092,9 +1092,7 @@ class BaseModelView(BaseView, ActionsMixin):
             if self.update_model(form, model):
                 if '_continue_editing' in request.form:
                     flash(gettext('Model was successfully saved.'))
-
-                    # Recreate form
-                    form = self.edit_form(obj=model)
+                    return redirect(request.full_path)
                 else:
                     return redirect(return_url)
 

flask_admin/tools.py

 import sys
-import warnings
 import traceback
 
 # Python 3 compatibility