frontail – realtime log stream in the browser

frontail is node.js application for serving tail -F output to browser.

Features

• search (Tab to focus, Esc to clear)
• basic authentication
• working over ssh
• log rotation
• auto-scrolling
• marking logs
• themes (default, dark)
• number of unread logs in favicon
• tailing multiple files
• highlighting

Installation

Note that as of 3.0.0 release, frontail requires Node.js 4 or newer. Earlier versions (2.x) work on legacy Node.js versions like 0.10 or 0.12.

npm install frontail -g

or use Docker image

docker run -d -v /var/log/syslog:/syslog -P mthenw/frontail /syslog

Usage

frontail [options] [file ...]

Options:

  -h, --help                    output usage information
  -V, --version                 output the version number
  -h, --host <host>             listening host, default 0.0.0.0
  -p, --port <port>             listening port, default 9001
  -n, --number <number>         starting lines number, default 10
  -l, --lines <lines>           number on lines stored in browser, default 2000
  -t, --theme <theme>           name of the theme (default, dark)
  -d, --daemonize               run as daemon
  -U, --user <username>         Basic Authentication username, option works only along with -P option
  -P, --password <password>     Basic Authentication password, option works only along with -U option
  -k, --key <key.pem>           Private Key for HTTPS, option works only along with -c option
  -c, --certificate <cert.pem>  Certificate for HTTPS, option works only along with -k option
  --pid-path <path>             if run as daemon file that will store the process id, default /var/run/frontail.pid
  --log-path <path>             if run as daemon file that will be used as a log, default /dev/null
  --ui-hide-topbar              hide topbar (log file name and search box)
  --ui-no-indent                don't indent log lines
  --ui-highlight                highlight words or lines if defined string found in logs, default preset
  --ui-highlight-preset <path>  custom preset for highlighting (see ./preset/default.json)
  --remote-host <remote_host>   setting the remote host for a tail over ssh (e.g: 192.168.0.2)
  --remote-user <remote_user>   setting the remote user for a tail over ssh, default root
  --remote-port <remote_port>   setting the remote port for a tail over ssh, default 22

Web interface runs on http://localhost:[port].

Tailing multiple files

[file ...] argument is passed directly to tail command which means that *, ? and other shell special characters can be used (I recommend reading Wildcards, Quotes, Back Quotes and Apostrophes in shell commands).

Highlighting

--ui-highlight option turns on highlighting in UI. By default preset from ./preset/defatult.json is used:

{
    "words": {
        "err": "color: red;"
    },
    "lines": {
        "err": "font-weight: bold;"
    }
}

which means that every "err" string will be in red and every line with "err" will be bolded. Custom preset can be provided by

New presets are very welcome. If you don't like default or you would like to share your, please create PR with json file.

Screenshot