Opening a program via a web browser

Recently I've been working on a project which allows users to replay their old league of legends games, currently I record the files to my server and the user is required to run league of legends with some params (my server, ip, the games encryption key, the games id and the server id). I can ask all my users to do this manually or using a batch file which I can serve them but I'd be interested in seeing if I could do this via a browser button click.

I had the idea from battlefield hardlines web based browser however figured that was done via an install (I'd rather not force users to install anything) and my second thought was magnet urls (however reading up on magnet urls I don't think I could use them)

Is this at all possible or is there some other way I can make this system more user friendly?

Thanks!