Revert "log/forward plugins: Extend dns query logging (#2240)" (#2256)

This reverts commit 8045aa279b510793a7c083a50de66e1df8871564.

7 files changed, 5 insertions, 55 deletions

diff --git a/plugin/forward/README.md b/plugin/forward/README.md
index 39c00bce8..c0a426aab 100644
--- a/plugin/forward/README.md
+++ b/plugin/forward/README.md
@@ -91,10 +91,6 @@ On each endpoint, the timeouts of the communication are set by default and autom
 * dialTimeout by default is 30 sec, and can decrease automatically down to 100ms
 * readTimeout by default is 2 sec, and can decrease automatically down to 200ms
 
-## Metadata
-
-* forward/resolving_proxy : provide the IP address and port of the upstream resolver used to resolve the current DNS query.
-
 ## Metrics
 
 If monitoring is enabled (via the *prometheus* directive) then the following metric are exported:
diff --git a/plugin/forward/forward.go b/plugin/forward/forward.go
index 02824d184..dfa1aaca1 100644
--- a/plugin/forward/forward.go
+++ b/plugin/forward/forward.go
@@ -12,7 +12,6 @@ import (
 
 	"github.com/coredns/coredns/plugin"
 	"github.com/coredns/coredns/plugin/debug"
-	"github.com/coredns/coredns/plugin/metadata"
 	clog "github.com/coredns/coredns/plugin/pkg/log"
 	"github.com/coredns/coredns/request"
 
@@ -60,15 +59,6 @@ func (f *Forward) Len() int { return len(f.proxies) }
 // Name implements plugin.Handler.
 func (f *Forward) Name() string { return "forward" }
 
-//declareMetadata adds to the context a metadata parameter which will return the passed value.
-func (f *Forward) declareMetadata(ctx context.Context, name string, value string) bool {
-	label := f.Name()+"/"+name
-	if metadata.IsLabel(label) {
-		return metadata.SetValueFunc(ctx, label, func() string { return value })
-	}
-	return false
-}
-
 // ServeDNS implements plugin.Handler.
 func (f *Forward) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (int, error) {
 
@@ -158,12 +148,10 @@ func (f *Forward) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg
 
 			formerr := state.ErrorMessage(dns.RcodeFormatError)
 			w.WriteMsg(formerr)
-			f.declareMetadata(ctx, "resolving_proxy", proxy.addr)
 			return 0, nil
 		}
 
 		w.WriteMsg(ret)
-		f.declareMetadata(ctx, "resolving_proxy", proxy.addr)
 		return 0, nil
 	}
 
diff --git a/plugin/log/README.md b/plugin/log/README.md
index 787ec49a2..65cca19c8 100644
--- a/plugin/log/README.md
+++ b/plugin/log/README.md
@@ -72,10 +72,6 @@ The following place holders are supported:
 * `{>do}`: is the EDNS0 DO (DNSSEC OK) bit set in the query
 * `{>id}`: query ID
 * `{>opcode}`: query OPCODE
-* `{local}`: server's IP address, for IPv6 addresses these are enclosed in brackets: `[::1]`
-* `{A}`: number of the A type answers in the response
-* `{AAAA}`: number of the AAAA type answers in the response
-* `{forward/resolving_proxy}`: if the query was forwarded to a resolver, the IP address and port of that replied resolver, else empty. The metadata plugin needs to be enabled to use this placeholder
 
 The default Common Log Format is:
 
diff --git a/plugin/log/log.go b/plugin/log/log.go
index 028188d51..f52a70344 100644
--- a/plugin/log/log.go
+++ b/plugin/log/log.go
@@ -57,7 +57,7 @@ func (l Logger) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg)
 		// 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.
 		if rule.Class[response.All] || rule.Class[class] {
-			rep := replacer.New(ctx, r, rrw, CommonLogEmptyValue)
+			rep := replacer.New(r, rrw, CommonLogEmptyValue)
 			rule.Log.Println(rep.Replace(rule.Format))
 		}
 
diff --git a/plugin/pkg/replacer/replacer.go b/plugin/pkg/replacer/replacer.go
index 1d65967e0..b9e1fcaa6 100644
--- a/plugin/pkg/replacer/replacer.go
+++ b/plugin/pkg/replacer/replacer.go
@@ -1,13 +1,11 @@
 package replacer
 
 import (
-	"context"
 	"strconv"
 	"strings"
 	"time"
 
 	"github.com/coredns/coredns/plugin/pkg/dnstest"
-	"github.com/coredns/coredns/plugin/metadata"
 	"github.com/coredns/coredns/request"
 
 	"github.com/miekg/dns"
@@ -33,7 +31,7 @@ type replacer struct {
 // values into the replacer. rr may be nil if it is not
 // available. emptyValue should be the string that is used
 // in place of empty string (can still be empty string).
-func New(ctx context.Context, r *dns.Msg, rr *dnstest.Recorder, emptyValue string) Replacer {
+func New(r *dns.Msg, rr *dnstest.Recorder, emptyValue string) Replacer {
 	req := request.Request{W: rr, Req: r}
 	rep := replacer{
 		replacements: map[string]string{
@@ -47,8 +45,6 @@ func New(ctx context.Context, r *dns.Msg, rr *dnstest.Recorder, emptyValue strin
 			"{size}":   strconv.Itoa(req.Len()),
 			"{remote}": addrToRFC3986(req.IP()),
 			"{port}":   req.Port(),
-			"{local}":  addrToRFC3986(req.LocalIP()),
-			"{forward/resolving_proxy}": getMetadata(ctx, "forward/resolving_proxy"),
 		},
 		emptyValue: emptyValue,
 	}
@@ -62,8 +58,6 @@ func New(ctx context.Context, r *dns.Msg, rr *dnstest.Recorder, emptyValue strin
 		rep.replacements["{duration}"] = strconv.FormatFloat(time.Since(rr.Start).Seconds(), 'f', -1, 64) + "s"
 		if rr.Msg != nil {
 			rep.replacements[headerReplacer+"rflags}"] = flagsToString(rr.Msg.MsgHdr)
-			rep.replacements["{A}"] = answersCount(rr.Msg, dns.TypeA)
-			rep.replacements["{AAAA}"] = answersCount(rr.Msg, dns.TypeAAAA)
 		}
 	}
 
@@ -169,30 +163,6 @@ func addrToRFC3986(addr string) string {
 	return addr
 }
 
-//getMetadata will return value from Metadata or empty string
-func getMetadata(ctx context.Context, label string) string {
-	if ctx != nil {
-		valueFunc := metadata.ValueFunc(ctx, label)
-		if valueFunc != nil {
-			return valueFunc()
-		}
-	}
-	return ""
-}
-
-//answersCount will calculate a number of answers which have the type passed
-func answersCount(m *dns.Msg, rtype uint16) string {
-	count := 0
-	if m != nil {
-		for i := 0; i < len(m.Answer); i++ {
-			if m.Answer[i].Header().Rrtype == rtype {
-				count++
-			}
-		}
-	}
-	return strconv.Itoa(count)
-}
-
 const (
 	timeFormat     = "02/Jan/2006:15:04:05 -0700"
 	headerReplacer = "{>"
diff --git a/plugin/pkg/replacer/replacer_test.go b/plugin/pkg/replacer/replacer_test.go
index 53b41510f..2fcaafc92 100644
--- a/plugin/pkg/replacer/replacer_test.go
+++ b/plugin/pkg/replacer/replacer_test.go
@@ -17,7 +17,7 @@ func TestNewReplacer(t *testing.T) {
 	r.SetQuestion("example.org.", dns.TypeHINFO)
 	r.MsgHdr.AuthenticatedData = true
 
-	replaceValues := New(nil, r, w, "")
+	replaceValues := New(r, w, "")
 
 	switch v := replaceValues.(type) {
 	case replacer:
@@ -47,7 +47,7 @@ func TestSet(t *testing.T) {
 	r.SetQuestion("example.org.", dns.TypeHINFO)
 	r.MsgHdr.AuthenticatedData = true
 
-	repl := New(nil, r, w, "")
+	repl := New(r, w, "")
 
 	repl.Set("name", "coredns.io.")
 	repl.Set("type", "A")
diff --git a/plugin/rewrite/condition.go b/plugin/rewrite/condition.go
index fc5bd2c66..f8d2a9f08 100644
--- a/plugin/rewrite/condition.go
+++ b/plugin/rewrite/condition.go
@@ -22,7 +22,7 @@ const (
 	NotMatch   = "not_match"
 )
 
-func newReplacer(r *dns.Msg) replacer.Replacer { return replacer.New(nil, r, nil, "") }
+func newReplacer(r *dns.Msg) replacer.Replacer { return replacer.New(r, nil, "") }
 
 // condition is a rewrite condition.
 type condition func(string, string) bool