This question comes from my poor understanding of how GDAL/OGR is supposed to work server-side, but before trying it I'd like to know if what I want is feasible with this library.
Basically, I am developing a webGIS application where the user should interact with a WFS. I'd like to give the user the possibility to download the data from this WFS as a format that the server does not provide as output so I need to convert it first.
I need the function ogr2ogr with the WFS driver to be able to convert the GML response of the server in (e.g.) Shapefile format.
My very basic question is: how can I call ogr2ogr which is installed on my server when the user click on (e.g.) a "Download" button?
My idea obvioulsy is to tie the onclick event with a JS function that calls ogr2ogr, but here my lack of knowledge in server-side web development does not le me go on.
Am I supposed to prepare a script (like a PHP) that internally calls ogr2ogr, or should I place the GDAL/OGR executables in a cgi-bin folder so that I can point and calling them with the required parameters?
I'd suggest investigating your server-middleware of choice; there's an excellent chance it supports OGR2OGR already if it's Open Source. The big two:
GeoServer has an ogr extension that can do what you want - https://docs.geoserver.org/stable/en/user/extensions/ogr.html
MapServer supports OGR too - https://mapserver.gis.umn.edu/output/ogr_output.html
Alternatively, you may want to consider investigating the WPS standard - but it's probably overkill if you're just changing formats.