vasc

A Go client for Varnish's administrative socket interface.

Disclaimer

vasc hasn't been used in the wild; it may very well be broken.

Simple usage

Assuming you have a Varnish instance

1. on host varnish
2. listening on port 10000
3. with its secret being mySuperStronkVarnishSecret

then in order to retrieve the instance's pid information, you'd want to use something like this:

package main

import (
	"log"
	"time"

	"github.com/azazeal/vasc"
)

func main() {
	cfg := vasc.Config{
		Secret:       "mySuperStronkVarnishSecret",
		ReadTimeout:  time.Minute, // Maximum amount of time to allow for reads
		WriteTimeout: time.Minute, // Maximum amount of time to allow for writes
	}

	client, err := vasc.Dial("tcp", "varnish:10000", cfg)
	if err != nil {
		log.Fatalf("failed dialing varnish: %v", err)
	}
	defer client.Close()

	code, data, err := client.Execute(nil, "pid", "-j")
	switch {
	case err != nil:
		log.Fatalf("failed executing: %v", err)
	case code == vasc.StatusClose:
		log.Fatal("varnish closed the connection!")
	case code != vasc.StatusOK:
		log.Fatalf("request failed with status: %d", code)
	}

	var pid struct {
		Master int `json:"master"`
		Worker int `json:"worker"`
	}

	if err := vasc.UnmarshalJSONResponse(data, &pid); err != nil {
		log.Fatalf("failed unmarshaling JSON response: %v", err)
	}

	log.Printf("master pid: %d", pid.Master)
	log.Printf("worker pid: %d", pid.Worker)
}

A list of commands that Varnish supports may be found here.