Conditional Nginx logging

Logging all HTTP traffic is often unnecessary. It especially applies to website which include not only text content but also all kind of additional components, like JavaScripts, stylesheets, images, fonts etc. You can select what you would like to log inclusively, but it is much easier to do this by conditional negative selection. First define log format, then create conditional mapping, last thing is to specify logger with decision variable. For instance:

log_format mylogformat '$remote_addr - $remote_user [$time_local] '
                       '"$request" $status $body_bytes_sent '
                       '"$http_referer" "$http_user_agent" "$gzip_ratio"';

map $request_uri $loggable {
    default                                             1;
    ~*\.(ico|css|js|gif|jpg|jpeg|png|svg|woff|ttf|eot)$ 0;

access_log /var/log/nginx/access.log mylogformat if=$loggable;

This way we are not going to log any of additional stuff and keep only regular pages in the log. Will be more useful for further traffic analysis than filtering out those things manually.