c4ab98c6e3
This checks if the next middleware to be called is nil, and if so returns ServerFailure and an error. This makes the next calling more robust and saves some lines of code. Also prefix the error with the name of the middleware to aid in debugging.
90 lines
2.6 KiB
Go
90 lines
2.6 KiB
Go
// Package log implements basic but useful request (access) logging middleware.
|
|
package log
|
|
|
|
import (
|
|
"log"
|
|
"time"
|
|
|
|
"github.com/miekg/coredns/middleware"
|
|
"github.com/miekg/coredns/middleware/metrics/vars"
|
|
"github.com/miekg/coredns/middleware/pkg/dnsrecorder"
|
|
"github.com/miekg/coredns/middleware/pkg/rcode"
|
|
"github.com/miekg/coredns/middleware/pkg/replacer"
|
|
"github.com/miekg/coredns/middleware/pkg/response"
|
|
"github.com/miekg/coredns/request"
|
|
|
|
"github.com/miekg/dns"
|
|
"golang.org/x/net/context"
|
|
)
|
|
|
|
// Logger is a basic request logging middleware.
|
|
type Logger struct {
|
|
Next middleware.Handler
|
|
Rules []Rule
|
|
ErrorFunc func(dns.ResponseWriter, *dns.Msg, int) // failover error handler
|
|
}
|
|
|
|
// ServeDNS implements the middleware.Handler interface.
|
|
func (l Logger) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (int, error) {
|
|
state := request.Request{W: w, Req: r}
|
|
for _, rule := range l.Rules {
|
|
if !middleware.Name(rule.NameScope).Matches(state.Name()) {
|
|
continue
|
|
}
|
|
|
|
rrw := dnsrecorder.New(w)
|
|
rc, err := middleware.NextOrFailure(l.Name(), l.Next, ctx, rrw, r)
|
|
|
|
if rc > 0 {
|
|
// There was an error up the chain, but no response has been written yet.
|
|
// The error must be handled here so the log entry will record the response size.
|
|
if l.ErrorFunc != nil {
|
|
l.ErrorFunc(rrw, r, rc)
|
|
} else {
|
|
answer := new(dns.Msg)
|
|
answer.SetRcode(r, rc)
|
|
state.SizeAndDo(answer)
|
|
|
|
vars.Report(state, vars.Dropped, rcode.ToString(rc), answer.Len(), time.Now())
|
|
|
|
w.WriteMsg(answer)
|
|
}
|
|
rc = 0
|
|
}
|
|
|
|
class, _ := response.Classify(rrw.Msg)
|
|
if rule.Class == response.All || rule.Class == class {
|
|
rep := replacer.New(r, rrw, CommonLogEmptyValue)
|
|
rule.Log.Println(rep.Replace(rule.Format))
|
|
}
|
|
|
|
return rc, err
|
|
|
|
}
|
|
return middleware.NextOrFailure(l.Name(), l.Next, ctx, w, r)
|
|
}
|
|
|
|
// Name implements the Handler interface.
|
|
func (l Logger) Name() string { return "log" }
|
|
|
|
// Rule configures the logging middleware.
|
|
type Rule struct {
|
|
NameScope string
|
|
Class response.Class
|
|
OutputFile string
|
|
Format string
|
|
Log *log.Logger
|
|
}
|
|
|
|
const (
|
|
// DefaultLogFilename is the default log filename.
|
|
DefaultLogFilename = "query.log"
|
|
// CommonLogFormat is the common log format.
|
|
CommonLogFormat = `{remote} ` + CommonLogEmptyValue + ` [{when}] "{type} {class} {name} {proto} {size} {>do} {>bufsize}" {rcode} {rsize} {duration}`
|
|
// CommonLogEmptyValue is the common empty log value.
|
|
CommonLogEmptyValue = "-"
|
|
// CombinedLogFormat is the combined log format.
|
|
CombinedLogFormat = CommonLogFormat + ` "{>opcode}"`
|
|
// DefaultLogFormat is the default log format.
|
|
DefaultLogFormat = CommonLogFormat
|
|
)
|