Harnessing the Power and Convenience of JavaScript for Each Request with the NGINX JavaScript Module

logging.js

function kvAccess(r) {
    var log = `${r.variables.time_iso8601} client=${r.remoteAddress} method=${r.method} uri=${r.uri} status=${r.status}`;
    r.rawHeadersIn.forEach(h => log += ` in.${h[0]}=${h[1]}`);
    r.rawHeadersOut.forEach(h => log += ` out.${h[0]}=${h[1]}`);
    return log;
}

export default { kvAccess }

rawheader_logging.conf

js_import  conf.d/logging.js;                    # Load JavaScript code from here
js_set     $access_log_headers logging.kvAccess; # Fill variable from JS function
log_format kvpairs $access_log_headers;          # Define special log format
	
server {
    listen 80;
    root /usr/share/nginx/html;
    access_log /var/log/nginx/access.log kvpairs;
}

# vim: syntax=nginx

For a discussion of these files, see: Harnessing the Power and Convenience of JavaScript for Each Request with the NGINX JavaScript Module