How to set up Piwik with Nginx and Tomcat?

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1

I’m running a webapp consisting out of several tomcat8 servlets. Above that configuration, nginx runs as a reverse proxy. Now i want to use piwik to gain some statistics about my webapp but i’m really struggling setting it up in nginx. I followed this tutorial, since it was the most up-to-date i found: How to Install Piwik with Nginx on Ubuntu 15.10

What i really don’t understand is how to configure the url mapping for piwik so that i can access it through the browser. The mapping for my webapps is as follows:

mysite.com -> https:/ localhost:8080/app1
mysite.com/app2 -> https://localhost:8080/app2
mysite.com/app3 -> https://localhost:8080/app3

This is how this mapping is defined in the “sites-enabled” config file:

server {
    listen 80;
    return 301 https://$host$request_uri;
}

server {
    listen 443;
    server_name mysite.com;

    ssl    on;
    ssl_certificate   "..."
    ssl_certificate_key    "..."

    ssl_prefer_server_ciphers on;
    ssl_protocols "..."
    ssl_ciphers "..."

    access_log /var/log/nginx/nginx.vhost.access.log;
    error_log /var/log/nginx/nginx.vhost.error.log;

    location / {

        proxy_set_header        Host $host;
        proxy_set_header        X-Real-IP $remote_addr;
        proxy_set_header        X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header        X-Forwarded-Proto $scheme;

        proxy_pass http://localhost:8080/app1/;
        proxy_read_timeout  90;
    }

   location /app2 {
       ... 
   }

...
}

All my apps are in tomcat8/webapps directory, but piwik is installed in /var/www/piwik (see Tut above). Like in the tutorial i have created a new config file “mysite.com.config”, but it is not working with the domain mysite.com.

So how do i have configure nginx so that i can access piwik via www.mysite.com/piwik?