Subreport which contains a JasperReports Server Report

I finally found what I should do in order to have a report of the jasperserver inside my subreport.

Let's say I have a "master report" in jasperserver and a ''slave report" = subreport which contains master report.

To put I had used this expression in the subreport "repo:/path_to_report/report_files/main_jrxml" and published it.

Then everything worked (subreport contained  a jasperserver report).

But I had another problem, when I updated my "master report", I saw that my "slave report" weren't updated.

So I opened the "main.jrxml" file of the "slave report" and I saw that instead of a subreport, it contained only a static text.

So I modified my "slave report" until I had a subreport with the expression "repo:/path_to_report/report_files/main_jrxml"

 -> 

Now when I modified my "master report", my "slave report" is updated.

PS : With this method, external resources like "input controls" or "images" in the "master report" can't be automatically updated in to the "slave report"