$Module rtstatus 3 "Real-time Varnish Status"

DESCRIPTION
===========

A vmod that lets you query your Varnish server for a JSON object containing
counters.

Visiting the URL ``/rtstatus.json`` on the Varnish server will produce an
``application/json`` response of the following format::

    {
        "uptime" : "0+16:12:58",
        "uptime_sec": 58378.00,
        "hitrate": 30.93,
        "load": 2.73,
        "varnish_version" : "[...]",
        "server_id": "[...]",
        "be_info":
        [
            { "server_name": "[...]", "happy": [...], "bereq_tot": [...], [...] },
            [...]
        ]
        "[counter]": {"type": "[...]", "ident": "[...]", "descr": "[...]", "value": [...] },
        [...]
    }

$Function VOID synthetic_json()

Description
	Returns a JSON object with relevant Varnish counters. Takes care
	of setting the content type.

$Function VOID synthetic_html()

Description
	Renders in a UI the JSON file obtained from the synthetic_json
	function. Takes care of setting the content type.

USAGE
=====

In your VCL you could then use this vmod along the following lines::

    vcl 4.0;

    import rtstatus;

    sub vcl_recv {
        if (req.url == "/rtstatus.json" || req.url == "/rtstatus.html") {
            return (synth(200));
        }
    }

    sub vcl_synth {
            if (req.url == "/rtstatus.json") {
                    rtstatus.synthetic_json();
                    return (deliver);
            }
            if (req.url == "/rtstatus.html") {
                    rtstatus.synthetic_html();
                    return (deliver);
            }
    }


NUMBERS
=======

Varnish version
	Varnish version installed on your server.

Varnish uptime
	Child uptime.

Hit ratio
	Absolute hitrate ratio. It is evaluated as: (n_hit) / (n_hit + n_miss).
	Note that uptime is not taken into consideration for this counter.

Avg hitrate
	Average hitrate since uptime. It is evaluated as: ((n_hit) / (n_hit + n_miss)) / uptime.

Avg load
	Average load since uptime. It is evaluated as: n_requests / uptime.

The list of counters is described in the ``varnish-counters(7)`` manual, and
for convenience backend counters are grouped by backend in the ``be_info``
field.