Directly hosting BlueMap with external webservers from a SQL storage

BlueMap’s internal webserver is very lightweight and quite fast, but it is quickly overwhelmed by a larger number of concurrent requests.

If you want to optimize the speed of your web-app for a larger audience, you can also host BlueMap directly with external webservers like NGINX or Apache. For this to work you need to do some configuration.

1. The goal
2. General Setup
3. NGINX
4. Apache

The goal

BlueMap renders and saved the map on your MySQL-Server. But the webapp requests them like they would be in a normal file-storage inside the webroot. So wee need some script that is translating those requests and fetching and providing the correct files from the MySQL-Server.

General Setup

Luckily BlueMap provides such a script. A PHP-Script to be exact. This means the first thing you need to do is to make sure that you have PHP (>= 7.4) installed on your webserver.
Then you go into the webroot and open the mysql.php, and set your MySQL-Connection settings there.

Important:
Make sure that your php-setup is working, otherwise you might accidentally leak those SQL-Connection-Settings to the world!

Now you need to configure your webserver, so that it rewrites all requests for which no static file exists to the mysql.php.

NGINX

On nginx this can be achieved with e.g. try_files $uri /mysql.php;.

With some context your website-config could look something like this:

server {
    listen 80;
    server_name yourdomain.com;
    
    # path to bluemap-webroot, bluemap can also be used in a sub-folder .. just adapt the paths accordingly
    root /var/www;
    
    location / {
        try_files $uri /mysql.php;
    }
    
    # Proxy requests to the live data interface of each map to bluemaps integrated webserver
    # If you have multiple servers you will need to proxy each map-id to the correct server
    location ~* /(maps/[^/\s]*/live/.*) {
        proxy_pass http://127.0.0.1:8100/$1;
    }
    
    location ~ \.php$ {
        include snippets/fastcgi-php.conf;
        fastcgi_pass unix:/run/php/php7.4-fpm.sock;
    }
}

Important:
The above config is just an example and not a complete config you can just copy&paste. You will need to adapt it to your setup!

Apache

Here is an example for how it could look like on Apache:

DocumentRoot /var/www/
<Directory /var/www/>
    allow from all
    Options FollowSymLinks
    Require all granted
  
    RewriteEngine On
    
    RewriteCond %{REQUEST_FILENAME} !-s
    RewriteCond %{REQUEST_FILENAME} !-l
    RewriteCond %{REQUEST_FILENAME} !-d
    # Rewrite request to the mysql.php
    RewriteRule ^.*$ /mysql.php [L]  
</Directory>

# Proxy requests to the live data interface to bluemaps integrated webserver  
ProxyPreserveHost On
ProxyPassMatch ^/(maps/[^/]*/live/.*) http://127.0.0.1:8100/$1

Important:
The above config is just an example and not a complete config you can just copy&paste. You will need to adapt it to your setup!