[gdal-dev] chaining vsicurl, vsizip *and* vsitar ?

[Landry Breuil]

Hi,

cadastral parcels are distributed in various formats in france, one of 
them being EDIGEO within .tar.bz2 - those are available online as 
opendata, but all in a specially complicated way:

shapefiles at 
https://cadastre.data.gouv.fr/data/etalab-cadastre/2020-07-01/shp/departements/01/cadastre-01-communes-shp.zip 
is readable via 
/vsizip//vsicurl/https://cadastre.data.gouv.fr/data/etalab-cadastre/2020-07-01/shp/departements/01/cadastre-01-communes-shp.zip

geojson at 
https://cadastre.data.gouv.fr/data/etalab-cadastre/2020-07-01/geojson/communes/01/01001/cadastre-01001-parcelles.json.gz
readable via 
/vsigzip//vsicurl/https://cadastre.data.gouv.fr/data/etalab-cadastre/2020-07-01/geojson/communes/01/01001/cadastre-01001-parcelles.json.gz

edigeo at 
https://cadastre.data.gouv.fr/data/dgfip-pci-vecteur/2020-07-01/edigeo/feuilles/01/01001/edigeo-010010000A01.tar.bz2 
-> for this one i havent found a way to access the .THF inside the 
.tar.bz2, be it via 
/vsitar//vsicurl/https://cadastre.data.gouv.fr/data/dgfip-pci-vecteur/2020-07-01/edigeo/feuilles/01/01001/edigeo-010010000A01.tar.bz2 
or even with /E0000A01.THF at the end of the URL

looking at https://gdal.org/user/virtual_file_systems.html#chaining
is it possible to access a .tar.bz2 file with /vsitar or it only 
supports gzipped tars (from reading gdal/port/cpl_vsil_tar.cpp that's 
the case) ? should it be a feature request to support bzip archives ? Is 
there any interest in supporting that ?

-- 
Landry Breuil