GeoNode provider does not work with newer versions of GeoNode

[gubuntu]

Describe the bug
Some valid GeoNode connections return no layers. I suspect it is because the QGIS provider needs to be updated for newer GeoNode versions.

How to Reproduce

1. Create a GeoNode connection to http://geonode.inasafe.org/ (GeoNode 2.9)
2. See how it connects and expands to show available layers
3. Create a GeoNode connection to http://geonode.ingc.gov.mz/
4. Test the connection and note that it is a successful connection
5. Note that the connection does not expand to show any layers.

QGIS and OS versions

QGIS 3
Mac OSX

[nirvn]

@timlinux , @myarjunar , do you guys think we could fix the geoserver provider prior to the next 3.10 LTR release? I also noticed newer geonode versions aren't fully supported. I would hate to see another core provider go unmaintained (looking at you GRASS provider).

[gioman]

I would hate to see another core provider go unmaintained (looking at you GRASS provider)

this matter should be seriously discussed at the next dev meeting, or before if possible?

[nyalldawson]

@timlinux do you know what's changed in the upstream api?

We've got a hard decision to make here -- if the provider is indeed completely broken with current geonode releases, we should disable it and avoid wasted user time trying to get it to work when it never will. (obviously, at the cost of user frustration due to a dropped feature).

I'm willing to have a go at repairing it, but I'm not up to speed with geonode itself so would appreciate some pointers on how the api has been changed...

(As @nirvn has pointed out -- the core grass provider (not the processing one) is also in the same completely broken state, and a similar decision needs to be made regarding this one)

[gioman]

the core grass provider (not the processing one) is also in the same completely broken state, and a similar decision needs to be made regarding this one

we should start by gentle pinging the main developer, Radim.

[nyalldawson]

Yes -- it would be great if @blazek could be involved in the current sponsored bug-fixing round and take a look at the outstanding issues. @blazek is this an option?

[gioman]

in the same completely broken state

just a note: for what I have seen recently is not "completely broken": on Linux it works. The problems are on Windows, where it is now not possible to create a GRASS location/mapset from scratch or opening an existing one (QGIS crashes).

[nyalldawson]

That's my understanding of the situation also, but to me that classifies as completely broken. It's a feature which crashes instantly on the platform the majority of our users use.

[blazek]

Regarding new GRASS location/mapset crash I am going to reply in the oldest open issue #28148 (#28554, #30317 marked as duplicates).

[myarjunar]

Hi everyone, I have investigated this problem and it turns out that this caused by the inconsistency of returned data from /api/layers endpoint from geonode. I still have no clue about which geonode version produce which returned data after checking various version of geonode.

So, what I am going to do on this are:

1. Remove the geonode version checking. Because I just found out that the geonode version has nothing to do with the format of the returned data.
2. Redo the logic to construct OWS endpoint of layers.

-> https://github.com/qgis/QGIS/blob/d92f9e79f7/src/core/geocms/geonode/qgsgeonoderequest.cpp#L259

[nyalldawson]

Great news @myarjunar -- thanks for taking this on!