cache_readiness.go

package main

import (
	"encoding/csv"
	"log"
	"strings"
	"strconv"
	"net/http"
	"github.com/gosuri/uitable"
	"fmt"
	"github.com/cheggaaa/pb"
	"sync"
)

type AccessRow struct {
	Visitors    int
	Hits        int
	Percent     float64
	Bandwidth   string
	Protocol    string
	Method      string
	Requests    string
	StatusCode  int
	Readiness   string
	XCacheable  string
	ContentType string
}


var accessStats string = `Visitors	Hits	%	Bandwidth	Protocol	Method	Requests
4	85973	1.51%	0.0 B	HTTP/1.1	HEAD	/
705	32430	0.57%	891.64 KiB	HTTP/1.1	GET	/
49	25008	0.44%	2.89 GiB	HTTP/1.1	GET	/da
...
`

func main() {
	r := csv.NewReader(strings.NewReader(accessStats))
	r.Comma = '\t'

	csvRows, err := r.ReadAll()
	if err != nil {
		log.Fatal(err)
	}

	accessRows := []*AccessRow{}
	for i, csvRow := range csvRows {
		if i == 0 {
			continue
		}
		visitors, _ := strconv.Atoi(csvRow[0])
		hits, _ := strconv.Atoi(csvRow[1])
		percent, _ := strconv.ParseFloat(strings.TrimSuffix(csvRow[2], "%"), 64)
		accessRow := &AccessRow{
			Visitors: visitors, Hits: hits, Percent: percent,
			Bandwidth: csvRow[3], Protocol: csvRow[4], Method: csvRow[5],
			Requests: csvRow[6],
		}
		accessRows = append(accessRows, accessRow)
	}

	fillVarnishReadiness(accessRows)

	table := uitable.New()
	table.AddRow(
		"Visitors", "Hits", "%", "Bandwidth", "Protocol", "Method", "Requests",
		"StatusCode", "Readiness", "X-Cacheable", "Content-Type")
	for _, row := range accessRows {
		table.AddRow(
			row.Visitors, row.Hits, row.Percent, row.Bandwidth, row.Protocol,
			row.Method, row.Requests, row.StatusCode, row.Readiness,
			row.XCacheable, row.ContentType,
		)
	}
	fmt.Println(table)
}

func fillVarnishReadiness(accessRows []*AccessRow) {
	var wg sync.WaitGroup
	wg.Add(len(accessRows))
	bar := pb.New(len(accessRows)).SetMaxWidth(80).Start()
	for _, row := range accessRows {
		go func(row *AccessRow) {
			defer wg.Done()
			defer bar.Increment()
			var res *http.Response
			var err error
			if row.Method == "HEAD" {
				res, err = http.Head("http://example.com" + row.Requests)
			} else if row.Method == "GET" {
				res, err = http.Get("http://example.com" + row.Requests)
			} else {
				row.Readiness = "UNKNOWN"
				row.XCacheable = "UNKNOWN"
				row.ContentType = "UNKNOWN"
				return
			}
			if err != nil {
				log.Print(err)
				row.Readiness = "ERROR"
				row.XCacheable = "ERROR"
				return
			}
			row.StatusCode = res.StatusCode
			row.Readiness = res.Header.Get("X-Cache")
			if row.Readiness == "" {
				row.Readiness = "ABSENT"
			}
			row.XCacheable = res.Header.Get("X-Cacheable")
			row.ContentType = res.Header.Get("Content-Type")
			if res.Header.Get("Content-Type") == "application/octet-stream" {
				row.Readiness = "BINARY_NO_CACHE"
			}
			if res.Header.Get("Cache-Control") == "private, max-age=3600" {
				row.Readiness = "BROWSER_CACHE_1H"
			}
		}(row)
	}
	wg.Wait()
	bar.Finish()
}