Additional options have been added to QGIS Server to improve the results of the GetCapabilities response, especially without the need to complete various fields within the QGIS Project configuration. These updates also enable many options to be set by an environment variable, or by providing headers from a proxy.
The following options have been added and will be resolved by the server in the following order:
<service>_SERVICE_URL
environment variable.SERVICE_URL
environment variable.X-Qgis-<service>-Service-Url
header.X-Qgis-Service-Url
header.Forwarded
header.X-Forwarded-Host
and X-Forwarded-Proto
headers.Host
header and the server protocol.This feature was developed by Stéphane Brunner