coredns/plugin/log/log.go
2022-07-10 11:06:33 -07:00

74 lines
2 KiB
Go

// Package log implements basic but useful request (access) logging plugin.
package log
import (
"context"
"time"
"github.com/coredns/coredns/plugin"
"github.com/coredns/coredns/plugin/pkg/dnstest"
clog "github.com/coredns/coredns/plugin/pkg/log"
"github.com/coredns/coredns/plugin/pkg/replacer"
"github.com/coredns/coredns/plugin/pkg/response"
"github.com/coredns/coredns/request"
"github.com/miekg/dns"
)
// Logger is a basic request logging plugin.
type Logger struct {
Next plugin.Handler
Rules []Rule
repl replacer.Replacer
}
// ServeDNS implements the plugin.Handler interface.
func (l Logger) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (int, error) {
state := request.Request{W: w, Req: r}
name := state.Name()
for _, rule := range l.Rules {
if !plugin.Name(rule.NameScope).Matches(name) {
continue
}
rrw := dnstest.NewRecorder(w)
rc, err := plugin.NextOrFailure(l.Name(), l.Next, ctx, rrw, r)
// If we don't set up a class in config, the default "all" will be added
// and we shouldn't have an empty rule.Class.
_, ok := rule.Class[response.All]
var ok1 bool
if !ok {
tpe, _ := response.Typify(rrw.Msg, time.Now().UTC())
class := response.Classify(tpe)
_, ok1 = rule.Class[class]
}
if ok || ok1 {
logstr := l.repl.Replace(ctx, state, rrw, rule.Format)
clog.Info(logstr)
}
return rc, err
}
return plugin.NextOrFailure(l.Name(), l.Next, ctx, w, r)
}
// Name implements the Handler interface.
func (l Logger) Name() string { return "log" }
// Rule configures the logging plugin.
type Rule struct {
NameScope string
Class map[response.Class]struct{}
Format string
}
const (
// CommonLogFormat is the common log format.
CommonLogFormat = `{remote}:{port} ` + replacer.EmptyValue + ` {>id} "{type} {class} {name} {proto} {size} {>do} {>bufsize}" {rcode} {>rflags} {rsize} {duration}`
// CombinedLogFormat is the combined log format.
CombinedLogFormat = CommonLogFormat + ` "{>opcode}"`
// DefaultLogFormat is the default log format.
DefaultLogFormat = CommonLogFormat
)