Supporting TCRS configuration through gridset selector

[dromagnoli]

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[dromagnoli]

Code depends on this GeoTools PR adding PROJ formatting support: geosolutions-it/geotools#84

MapML XML/XSD has been updated to modify the projection elements.
It was tied to ProjType which is an enum only supporting the 4 Built-in Projections (WGS84,CBMTILE,APSTILE,OSMTILE).
I have created a WrappingProjType which encapsulates the ProjType and modified projection elements of xsd/xml to be simple String instead of ProjType type. Please, let me know if that's ok.

Side Question on the next task related to Projection support:
SW.4.1.19 requires allowing GeoServer admin to set the default projection MapML URL.
At the moment I think is it already supported.
Admin can specify default Projection during layer configuration, by specifying a MapML:CRS as Declared CRS and select Reproject Native to Declared.

The generated LayerPreview will use that CRS.
http://localhost:8080/geoserver/topp/wms?service=WMS&version=1.1.0&request=GetMap&layers=topp%3Astates&bbox=-2154706.877127081%2C2763762.2272634404%2C3844204.014332743%2C5981537.174078367&width=768&height=411&srs=MapML%3AUTM14WGS84Quad&styles=&format=text%2Fhtml%3B%20subtype%3Dmapml

Is it what is requested?
Or do we actually need a different feature where we want the possibility to specify a Declared CRS and specify a different Default output CRS?

[prushforth]

MapML XML/XSD has been updated to modify the projection elements.
It was tied to ProjType which is an enum only supporting the 4 Built-in Projections (WGS84,CBMTILE,APSTILE,OSMTILE).
I have created a WrappingProjType which encapsulates the ProjType and modified projection elements of xsd/xml to be simple String instead of ProjType type. Please, let me know if that's ok.

That is ok! One thing I don't want to have happen is to allow the projection name string to contain :, as I don't want users to use for example, "EPSG:4326" as the name of a TCRS, since they are definitely not the same kind of thing. I noticed that the data type used in the rnc was string but in the xsd it's anyURI which might lead to trouble, but I suppose even a plain string without the : can be considered a URI. If I use the example pictured, we want to use MapML:UTM14WGS84QUAD as the value required by GeoServer (GetMap srsName parameter requirement), but inside the HTML and MapML document it should be used without the prefix:

<mapml-viewer projection="UTM14WGS84QUAD" ...>...</mapml-viewer>

Side Question on the next task related to Projection support:
SW.4.1.19 requires allowing GeoServer admin to set the default projection MapML URL.
At the moment I think is it already supported.

You are correct.

Admin can specify default Projection during layer configuration, by specifying a MapML:CRS as Declared CRS and select Reproject Native to Declared.

This is done, thanks!

[dromagnoli]

One thing I don't want to have happen is to allow the projection name string to contain :

This is already addressed, there is also a note in the GridSet to TCRS Selector documentation that reports that:
https://github.com/geosolutions-it/geoserver/pull/375/files#diff-3bb5273b2d308af6af5f3b5f39e968a4307b50fe4084adf3e6dda3f2c8935fe8R73

Quoting:
Gridsets containing ":" character in the name won't be listed

[aaime]

Overall looks good, see comments below

[aaime]

Since this is a java bean, why isn't it injected through he constructor (or like before, using autowiring?)

[aaime]

And what if we want to use MapML on Mars or the Sun? (e.g., IAU authority)

[aaime]

Good. I would also check that:

• The code shows up in "CRS.getSupportedCodes()
• A GUI test that adds a built-in valid griset as a valid TRCS, and after the submission, the CRS class can find it