Use separate DNSRequestContext struct for adding DNS context to connections

resolver/ipinfo.go

@@ -44,8 +44,8 @@ type ResolvedDomain struct {
 	// information.
 	Resolver *ResolverInfo
 
-	// RRCache holds the DNS response that was received for this domain.
-	RRCache *RRCache
+	// DNSRequestContext holds the DNS request context.
+	DNSRequestContext *DNSRequestContext
 
 	// Expires holds the timestamp when this entry expires.
 	// This does not mean that the entry may not be used anymore afterwards,

resolver/rr_context.go

@@ -0,0 +1,39 @@
+package resolver
+
+import (
+	"time"
+
+	"github.com/miekg/dns"
+)
+
+// DNSRequestContext is a static structure to add information to DNS request connections.
+type DNSRequestContext struct {
+	Domain   string
+	Question string
+	RCode    string
+
+	ServedFromCache bool
+	RequestingNew   bool
+	IsBackup        bool
+	Filtered        bool
+
+	Modified time.Time
+	Expires  time.Time
+}
+
+// ToDNSRequestContext returns a new DNSRequestContext of the RRCache.
+func (rrCache *RRCache) ToDNSRequestContext() *DNSRequestContext {
+	return &DNSRequestContext{
+		Domain:   rrCache.Domain,
+		Question: rrCache.Question.String(),
+		RCode:    dns.RcodeToString[rrCache.RCode],
+
+		ServedFromCache: rrCache.ServedFromCache,
+		RequestingNew:   rrCache.RequestingNew,
+		IsBackup:        rrCache.IsBackup,
+		Filtered:        rrCache.Filtered,
+
+		Modified: time.Unix(rrCache.Modified, 0),
+		Expires:  time.Unix(rrCache.Expires, 0),
+	}
+}

resolver/rrcache.go

@@ -2,7 +2,6 @@ package resolver
 
 import (
 	"context"
-	"encoding/json"
 	"fmt"
 	"net"
 	"time"
@@ -45,25 +44,6 @@ type RRCache struct {
 	Modified int64
 }
 
-func (rrCache *RRCache) MarshalJSON() ([]byte, error) {
-	var record = struct {
-		RRCache
-
-		Question string
-		RCode    string
-		Modified time.Time
-		Expires  time.Time
-	}{
-		RRCache:  *rrCache,
-		Question: rrCache.Question.String(),
-		RCode:    dns.RcodeToString[rrCache.RCode],
-		Modified: time.Unix(rrCache.Modified, 0),
-		Expires:  time.Unix(rrCache.Expires, 0),
-	}
-
-	return json.Marshal(record)
-}
-
 // ID returns the ID of the RRCache consisting of the domain and question type.
 func (rrCache *RRCache) ID() string {
 	return rrCache.Domain + rrCache.Question.String()