Filter the password from a request in the nginx access log.

filter-password.nginx.conf

log_format filtered_log '$remote_addr - $http_host - $remote_user [$time_local] {$request_time} {$upstream_response_time} $upstream_addr'
      '"$filtered_request" $status $body_bytes_sent '
      '"$http_referer" "$http_user_agent"';

server {
  root /home/ubuntu/password_test/www;
  index index.html index.htm;
  server_name password_test;

  location / {
    try_files $uri $uri/ /index.html;

    #Strip password in access.log
    set $filtered_request $request;
    if ($filtered_request ~* (.*)(password)=[^&]*(.*)) {
      set $filtered_request $1$2=[FILTERED]$3;
    }

    access_log  /home/ubuntu/password_test/logs/access.log filtered_log;
  }
}