Skip to content

Directly hosting BlueMap with external webservers

mindgam3s edited this page Apr 8, 2021 · 16 revisions

If you want to optimize the speed of your map, you can also host BlueMap directly with external webservers like NGINX or Apache. For this to work you need to do some configuration:

The goal

BlueMap renders and saves the map in a lot of small parts called "tiles". Those tiles are saved in individual files in a tree-like folder-structure here: <webroot>/data/<map-id>/. The file-data is in json-format. But the files are also compressed with GZip. The problem now is, that the web-app (browser) is asking for the uncompressed .json files, but a normal webserver only finds the compressed ones.

For example: the web-app is asking for a tile: /data/world/hires/x9/z-8.json. If your webserver is now searching for that file, it will not find it, because the file it needs is actually this one: /data/world/hires/x9/z-8.json.gz! And on top of that it is compressed.

So we need to do two things:

  • Internally redirect the request to the .gz variant of the file
  • Tell the browser that the file we send is actually GZip compressed and the browser has to decompress it before giving it to the web-app. (We can do this with the http-header Content-Encoding: gzip)

Optionally:

  • If a map-tile (/data/...) does not exist, instead of returning a 404 we want to respond with 200 and this file: /assets/emptyTile.json (This removes harmless but annoying 404 errors in the browsers console)

Live data interface

If you are using a plugin/mod you usually have live-updating player-markers on your map. For those to work with an external web-server you will also need to reverse-proxy all requests to /live/* to the builtin web-server.

NGINX

With NGINX it is actually only one config-line that does both things: gzip_static always;

So with some context your website-config could look 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 $uri/ =404 ;
  }
  
  # map-tiles are stored compressed, and they have a fallback file that should be returned if the tile does not exist
  location /data/ {
    error_page 404 =200 /assets/emptyTile.json;
    gzip_static always;
  }

  # Proxy requests to the live data interface to bluemaps integrated webserver
  location /live/ {
    proxy_pass http://127.0.0.1:8100;
  }
}

Apache2

Apache2 Modules

this needs the HEADERS, REWRITE and all PROXY (PROXY and PROXY_HTTP) modules for Apache to be enabled!
you can check your anabled modules via # apache2ctl -M and check whether the modules are enabled.
after installing any missing module via # a2enmod MODULENAME don't forget to restart apache2!

Apache2 configuration (apache2.conf)

DocumentRoot /var/www/
<Directory /var/www/>
  allow from all
  Options FollowSymLinks
  Require all granted
  SetEnv no-gzip

  RewriteEngine on

  # Make sure the browser supports gzip encoding before we send it
  # without it, Content-Type will be "application/x-gzip"
  RewriteCond %{HTTP:Accept-Encoding} \b(x-)?gzip\b
  RewriteCond %{REQUEST_FILENAME}.gz -s
  RewriteRule ^(.+) $1.gz
  
  # Check if file doesn't exists and is a data file
  RewriteCond %{REQUEST_URI} "^/data"
  RewriteCond %{REQUEST_FILENAME} !-s
  RewriteCond %{REQUEST_FILENAME} !-l
  RewriteCond %{REQUEST_FILENAME} !-d
  # Rewrite request to emptyTile
  RewriteRule ^.*$ /assets/emptyTile.json [L]

  # Also add a content-encoding header to tell the browser to decompress
  <FilesMatch .gz$>
    ForceType application/json
    Header set Content-Encoding gzip
  </FilesMatch>
  
</Directory>
  
# Proxy requests to the live data interface to bluemaps integrated webserver  
ProxyPreserveHost On
ProxyPass /live/ http://127.0.0.1:8100/live/
ProxyPassReverse /live/ http://127.0.0.1:8100/live/

important additional note

If you set the bluemap webroot via webserver.conf and render.conf to be somewhere else than the default webserver root (e.g. /var/www/bluemap/ instead of /var/www/ ) you have to make sure that you adjust the proxy configuration to match the new path!

ProxyPass /bluemap/live/ http://127.0.0.1:8100/live/
ProxyPassReverse /bluemap/live/ http://127.0.0.1:8100/live/

otherwise your proxy does not accept the redirection correctly and you will not have player data available!

Caddy

Here is a solution if you are using Caddy:

http://your-domain {
  root * /usr/share/caddy/
  file_server

  reverse_proxy /live/*  http://127.0.0.1:8100

  @JSONgz {
    path *.json
    file {
      try_files {path}.gz
    }
  }

  route @JSONgz {
    rewrite {http.matchers.file.relative}
    header Content-Type application/json
    header Content-Encoding gzip
  }

}