Port Map Download from older GeoNode

[ridoo]

Is your feature request related to a problem? Please describe.
Older versions of GeoNode offered a "Download Map" button. This is not available anymore since (I guess) v4.x.

Describe the solution you'd like
A feature which would allow an authorized user to download all assets available from a map as zip file. The zip should include all visible datasets (allowed to be downloaded) in a plain data format (like shp or tif) and (optionally) all linked datasets as well.

Describe alternatives you've considered
Fragments (?) of the old map_download view made it into v4.4.x and also even live on master until today. I thought on porting stuff to v4.4.x but my doubts grow as longer I look at the code and corresponding history. These are the parts I could found:

• 4.4.x geonode maps/templates: map_download.html
• 3.3.x geonode maps.views: map_download
• 3.3.x geonode-mapstore-client hookset: map_download_template (commented out)

I am pretty sure, that this is not working for v4.4.x anymore, but is there a chance to re-activate this feature again, or will it be dropped forever? I can offer help on that (with some customer funding).

Additional context

At the moment, I do not understand how this actually worked on v3.3.x as the client hookset is disabled and there seems no URL config for it. However, the client contains a Download Map button on the maps detail page.

However, I did not find any decision or documentation about the map download feature and if it is considered to be re-added to future versions of GeoNode. Perhaps there were good reasons to remove this feature.

[giohappy]

@ridoo This is one of the pieces of code that are planned to be removed in GEoNode 5. It is legacy code, not maintained and, was you said, probably not working.

At the moment we have the option to enable the download/upload MapStore tool through Viewers. It allows you to download the MapStore map config. However what happens if you upload it back into a map in GeoNode is "Undefined behavior" I guess. The connections between the maplayers inside the map config and the GeoNode datasets are probably lost. And you might upload it in a different GeoNode where the original datasets are not available. The map should still work, but you won't have the expected connections with GeoNode datasets.

Even if we enhance the MapStore map download to integrate with GeoNode, or we resurrect the GeoNode map download functionality, I'm not sure what should be supported. How do you manage uploading a map from one GeoNode to another GeoNode? Should it be forbidden if references to the datasets cannot recovered?

[ridoo]

@giohappy thanks for the insights. I understand your plans, not tested the download in 3.x to be honest.

However, the intended use of a downloaded map goes not that far to have a bijective isomorph mapping so that geonode -> zip -> geonode would result in the exact same map. Instead the mere download would be sufficient.

[giohappy]

@ridoo I get get your point. Basically allowing to batch download the datasets in a map, where the user has permissions to do so.

It will need to be carefully design to not impact too much on the server. GeoNode doesn't assume that file assets are available for datasets. Dataset download uses the Geoserver WPS download process when the dataset is not backed by a file. Perfoming the procedure in batch would be a high load for Geoserver.

I'm not saying it cannot be done but we probably need to add more tooling and control over the download service.

[ridoo]

@giohappy valid points, indeed. I created a discussion thread to reduce the noise here and sort out different requirements and priorities first.