firehol/netdata

// SPDX-License-Identifier: GPL-3.0-or-later

package squid

import (
    "bufio"
    "fmt"
    "io"
    "strconv"
    "strings"

    "github.com/netdata/netdata/go/plugins/plugin/go.d/pkg/web"
)

const (
    // https://wiki.squid-cache.org/Features/CacheManager/Index#controlling-access-to-the-cache-manager
    urlPathServerStats = "/squid-internal-mgr/counters"
)

var statsCounters = map[string]bool{
    "client_http.kbytes_in":      true,
    "client_http.kbytes_out":     true,
    "server.all.errors":          true,
    "server.all.requests":        true,
    "server.all.kbytes_out":      true,
    "server.all.kbytes_in":       true,
    "client_http.errors":         true,
    "client_http.hits":           true,
    "client_http.requests":       true,
    "client_http.hit_kbytes_out": true,
}

func (s *Squid) collect() (map[string]int64, error) {
    mx := make(map[string]int64)

    if err := s.collectCounters(mx); err != nil {
        return nil, err
    }

    return mx, nil
}

func (s *Squid) collectCounters(mx map[string]int64) error {
    req, err := web.NewHTTPRequestWithPath(s.RequestConfig, urlPathServerStats)
    if err != nil {
        return fmt.Errorf("failed to create '%s' request: %w", urlPathServerStats, err)
    }

    return web.DoHTTP(s.httpClient).Request(req, func(body io.Reader) error {
        sc := bufio.NewScanner(body)

        for sc.Scan() {
            key, value, ok := strings.Cut(sc.Text(), "=")
            if !ok {
                continue
            }

            key, value = strings.TrimSpace(key), strings.TrimSpace(value)

            if !statsCounters[key] {
                continue
            }

            v, err := strconv.ParseInt(value, 10, 64)
            if err != nil {
                s.Debugf("failed to parse key %s value %s: %v", key, value, err)
                continue
            }

            mx[key] = v
        }

        if len(mx) == 0 {
            return fmt.Errorf("unexpected response from '%s': no metrics found", req.URL)
        }
        return nil
    })
}