Thumbnail upload issue

[bieganowski]

Expected Behavior

By saving the map, for the first time, it should be possible to upload a thumb

Actual Behavior

The new saved map does not have the thumb loaded

Steps to Reproduce the Problem

1. Login as admin
2. Click on Maps > Create Map
3. From Options menu select Catalog > Add a layer
4. From Options menu select Save as
5. Insert a thumbnails and a Name
6. Click on Save as
7. Go back to Maps list

Specifications

• GeoNode version:
• Installation method (manual, GeoNode Docker, SPCGeoNode Docker):
• Platform:
• Additional details:

[bieganowski]

Issue is caused by two factors:

• the default thumbnail generation expects a thumbnail name to have .png extension. Loading any other file format and calling creat_thumbnail, even with overwrite=False (as in the case of Maps creation), causes regeneration of the thumbnail, since the generation script fails to recognize the thumbnail:

  geonode/geonode/thumbs/thumbnails.py

  Line 100 in c1007fc

  if thumb_exists(thumbnail_name) and not overwrite:

• django-mapstore-adapter first orders thumbnail saving, which triggers asynchronous task, which creates a default thumbnail:
  https://github.com/GeoNode/geonode-mapstore-client/blob/6520cb78ceda6ce86ab7091f38c0e5ec86a3968d/mapstore2_adapter/plugins/serializers.py#L285
  only to overwrite the thumbnail directly after it:
  https://github.com/GeoNode/geonode-mapstore-client/blob/6520cb78ceda6ce86ab7091f38c0e5ec86a3968d/mapstore2_adapter/plugins/serializers.py#L298
  Such an order of called function causes races in thumbnail creation, making it impossible to determine which thumbnail is assigned to a resource.