vslparser

Simple and efficient parser of varnishlog output written in Go.

Description

vslparser is a Go module which provides basic functionality required for further processing of varnishlog output.

varnishlog output is made up of entries, such as Request or BeReq. The provided Parse function parses a single such entry and returns a convenient Entry struct. Little processing is required to obtain the Entry, only line splitting and basic sanity checks are performed.

The Entry provides a range of convenience methods which further parse the entry. This way, only the fields which actually need to be parsed are ever processed. The parsing process is therefore about as efficient as it gets, and the API is easy to use at the same time.

Example

Compile this minimal example to start "varnishlog" and use vslparser to parse its standard output.

package main

import (
	"bufio"
	"fmt"
	"log"
	"os/exec"

	"github.com/Showmax/vslparser"
)

func main() {
	cmd := exec.Command("varnishlog") // Add "-b" to only process back-end requests.
	stdout, err := cmd.StdoutPipe()
	if err != nil {
		log.Fatal(err)
	}
	if err := cmd.Start(); err != nil {
		log.Fatal(err)
	}
	scanner := bufio.NewScanner(stdout)
	for {
		entry, err := vslparser.Parse(scanner)
		if err != nil {
			log.Fatal(err)
		}
		fmt.Println(entry)
	}
}

Contributing

Contributions are welcome. Open a PR and we'll get to you soon.

License

Apache 2.0.