External configuration of Project_Version in gpr file - ada

Question

With gnatpro 19.1, I'm trying to add gnathub to my project and am wondering how to set dynamically Project_Version as in:
package Dashboard is
for Project_Version use #git --describe --tags#; -- this needs to be updated.
end Dashboard;
I can't think of any simple way to do it.
A solution would be to use a Makefile that would configure a .gpr.in file but it seems contrived to change my whole buildchain just to add a version to the sonar config.
A simple, not automated solution, is to call the project with another switch:
gnathub -P Foo.gpr --plugins sonar-config,sonar-scanner\
--targs:sonar-scanner -Dsonar.projectVersion=$(git describe --tags)
But this is not really usable.
Similar question is to add the option -Dsonar.branch.name=$(git branch). AFAICT, the package Dashboard, as per the documentation has no Switch switch.
Is there any solution other than passing the extra arguments or forking gnatdashboard?

Answer 1

The best solution seems to reside in automating this configuration with a tool like Make.
For example, one can define the following Makefile:
# This target runs all the plugins listed
# in the section Dashboard.plugins of your project’s gpr
# sonar-config and sonar-scanner shall not be listed therein.
analyzes:
gnathub -P project
# This uses gnathub API to get the object dir where sonar-config file will be generated
OBJECT_DIR = $(shell gnathub -P project --exec object_dir.py 2>/dev/null | tail -n 1)
SONAR_PROPERTIES = $(OBJECT_DIR)/gnathub/sonar/sonar-project.properties
PROJECT_VERSION = $(shell git describe --tags)
BRANCH_NAME = $(shell git rev-parse --abbrev-ref HEAD)
# Uses gnathub to generate sonar properties file.
# Replaces the projectVersion and add branch name
# (notice that, on sonar, the branch name shall not be specified on your "master" branch)
$(SONAR_PROPERTIES): analyzes
gnathub -P project --plugins sonar-config --incremental
#sed -i "s/\(sonar.projectVersion = \).*/\1$(PROJECT_VERSION)/" $#
ifneq ($(BRANCH_NAME), master)
#echo "sonar.branch.name = $(BRANCH_NAME)" >> $#
endif
sonar: $(SONAR_PROPERTIES)
gnathub -P project --plugins sonar-scanner --incremental
.PHONY: sonar analyzes
Where object_dir.py is:
#!/usr/bin/env python
import GNAThub;
print (GNAThub.Project.object_dir());
Then:
$make sonar
Would run the analyzes and update them with the correct version and branch name (if necessary) to the SonarQube server.