Luzilla/dnsbl_exporter

package rbl

import (
    "net"

    "github.com/Luzilla/dnsbl_exporter/pkg/dns"

    "golang.org/x/exp/slog"
)

type Target struct {
    Host string
    IP   net.IP
}

type Resolver struct {
    logger *slog.Logger
    util   *dns.DNSUtil
}

func NewRBLResolver(logger *slog.Logger, util *dns.DNSUtil) *Resolver {
    return &Resolver{
        logger: logger,
        util:   util,
    }
}

func (r *Resolver) Do(target string, c chan<- Target, done func()) {
    defer done()

    addr := net.ParseIP(target)
    if addr != nil {
        // already an IP
        r.logger.Info("we had an ip already", slog.String("ip", target))
        c <- Target{
            Host: target,
            IP:   addr,
        }
        return
    }

    ipsA, err := r.util.GetARecords(target)
    if err != nil {
        r.logger.Error("error fetching A-records for target", slog.String("msg", err.Error()))
        return
    }

    for _, i := range ipsA {
        a := net.ParseIP(i)
        if a == nil {
            r.logger.Error("address failed parsing", slog.String("ip", i))
            continue
        }
        c <- Target{
            Host: target,
            IP:   a,
        }
    }
}