Isolate logger

6 files changed, 41 insertions, 21 deletions

diff --git a/cmd/zdns/main.go b/cmd/zdns/main.go
index 6571c63..9242bad 100644
--- a/cmd/zdns/main.go
+++ b/cmd/zdns/main.go
@@ -1,13 +1,13 @@
 package main
 
 import (
-	"log"
 	"os"
 	"path/filepath"
 
 	"flag"
 
 	"github.com/mpolden/zdns"
+	"github.com/mpolden/zdns/log"
 )
 
 const (
@@ -44,7 +44,7 @@ func main() {
 		return
 	}
 
-	log := log.New(os.Stderr, logPrefix, 0)
+	log := log.New(os.Stderr, logPrefix)
 	srv, err := newServer(log, *conf)
 	if err != nil {
 		log.Fatal(err)
diff --git a/cmd/zdns/main_test.go b/cmd/zdns/main_test.go
index 8b254c2..e0355e3 100644
--- a/cmd/zdns/main_test.go
+++ b/cmd/zdns/main_test.go
@@ -4,6 +4,8 @@ import (
 	"io/ioutil"
 	"os"
 	"testing"
+
+	"github.com/mpolden/zdns/log"
 )
 
 func handleErr(t *testing.T, fn func() error) {
@@ -41,7 +43,7 @@ hijack_mode = "zero"
 		t.Fatal(err)
 	}
 	defer handleErr(t, func() error { return os.Remove(f) })
-	srv, err := newServer(nil, f)
+	srv, err := newServer(log.New(ioutil.Discard, ""), f)
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/dns/proxy.go b/dns/proxy.go
index acfd03e..d56e3c8 100644
--- a/dns/proxy.go
+++ b/dns/proxy.go
@@ -1,13 +1,13 @@
 package dns
 
 import (
-	"log"
 	"net"
 	"strings"
 	"time"
 
 	"github.com/miekg/dns"
 	"github.com/mpolden/zdns/cache"
+	"github.com/mpolden/zdns/log"
 )
 
 // TypeA represents the resource record type A, an IPv4 address.
diff --git a/log/logger.go b/log/logger.go
new file mode 100644
index 0000000..7de3c02
--- /dev/null
+++ b/log/logger.go
@@ -0,0 +1,23 @@
+package log
+
+import (
+	"io"
+	"log"
+)
+
+// A Logger wraps a standard log.Logger.
+type Logger struct {
+	logger *log.Logger
+}
+
+// New creates a new logger wrapping a standard log.Logger.
+func New(out io.Writer, logPrefix string) *Logger {
+	logger := &Logger{logger: log.New(out, logPrefix, 0)}
+	return logger
+}
+
+// Printf delegates to Printf of log.Logger.
+func (l *Logger) Printf(format string, v ...interface{}) { l.logger.Printf(format, v...) }
+
+// Fatal delegates to Fatal of log.Logger.
+func (l *Logger) Fatal(v ...interface{}) { l.logger.Fatal(v...) }
diff --git a/server.go b/server.go
index de1279f..8b6e2ce 100644
--- a/server.go
+++ b/server.go
@@ -3,7 +3,6 @@ package zdns
 import (
 	"fmt"
 	"io"
-	"log"
 	"net"
 	"net/http"
 	"net/url"
@@ -15,6 +14,7 @@ import (
 
 	"github.com/mpolden/zdns/dns"
 	"github.com/mpolden/zdns/hosts"
+	"github.com/mpolden/zdns/log"
 )
 
 const (
@@ -113,12 +113,6 @@ func nonFqdn(s string) string {
 	return s
 }
 
-func (s *Server) logf(format string, v ...interface{}) {
-	if s.logger != nil {
-		s.logger.Printf(format, v...)
-	}
-}
-
 func (s *Server) readSignal() {
 	for {
 		select {
@@ -128,15 +122,15 @@ func (s *Server) readSignal() {
 		case sig := <-s.signal:
 			switch sig {
 			case syscall.SIGHUP:
-				s.logf("received signal %s: reloading filters", sig)
+				s.logger.Printf("received signal %s: reloading filters", sig)
 				s.loadHosts()
 			case syscall.SIGTERM, syscall.SIGINT:
-				s.logf("received signal %s: shutting down", sig)
+				s.logger.Printf("received signal %s: shutting down", sig)
 				if err := s.Close(); err != nil {
-					s.logf("close failed: %s", err)
+					s.logger.Printf("close failed: %s", err)
 				}
 			default:
-				s.logf("received signal %s: ignoring", sig)
+				s.logger.Printf("received signal %s: ignoring", sig)
 			}
 		}
 	}
@@ -164,7 +158,7 @@ func (s *Server) loadHosts() {
 			var err error
 			hs1, err = readHosts(h.URL, h.timeout)
 			if err != nil {
-				s.logf("failed to read hosts from %s: %s", h.URL, err)
+				s.logger.Printf("failed to read hosts from %s: %s", h.URL, err)
 				continue
 			}
 		}
@@ -172,7 +166,7 @@ func (s *Server) loadHosts() {
 			for name, ipAddrs := range hs1 {
 				hs[name] = ipAddrs
 			}
-			s.logf("loaded %d hosts from %s", len(hs1), src)
+			s.logger.Printf("loaded %d hosts from %s", len(hs1), src)
 		} else {
 			removed := 0
 			for hostToRemove := range hs1 {
@@ -182,14 +176,14 @@ func (s *Server) loadHosts() {
 				}
 			}
 			if removed > 0 {
-				s.logf("removed %d hosts from %s", removed, src)
+				s.logger.Printf("removed %d hosts from %s", removed, src)
 			}
 		}
 	}
 	s.mu.Lock()
 	s.hosts = hs
 	s.mu.Unlock()
-	s.logf("loaded %d hosts in total", len(hs))
+	s.logger.Printf("loaded %d hosts in total", len(hs))
 }
 
 // Close terminates all active operations and shuts down the DNS server.
@@ -248,6 +242,6 @@ func (s *Server) hijack(r *dns.Request) *dns.Reply {
 
 // ListenAndServe starts a server on configured address and protocol.
 func (s *Server) ListenAndServe() error {
-	s.logf("listening on %s [%s]", s.Config.DNS.Listen, s.Config.DNS.Protocol)
+	s.logger.Printf("listening on %s [%s]", s.Config.DNS.Listen, s.Config.DNS.Protocol)
 	return s.proxy.ListenAndServe(s.Config.DNS.Listen, s.Config.DNS.Protocol)
 }
diff --git a/server_test.go b/server_test.go
index d76b944..b323ef2 100644
--- a/server_test.go
+++ b/server_test.go
@@ -13,6 +13,7 @@ import (
 
 	"github.com/mpolden/zdns/dns"
 	"github.com/mpolden/zdns/hosts"
+	"github.com/mpolden/zdns/log"
 )
 
 const hostsFile1 = `
@@ -101,7 +102,7 @@ func testServer(t *testing.T, refreshInterval time.Duration) (*Server, func()) {
 	if err := conf.load(); err != nil {
 		t.Fatal(err)
 	}
-	srv, err = NewServer(nil, conf)
+	srv, err = NewServer(log.New(ioutil.Discard, ""), conf)
 	if err != nil {
 		defer cleanup()
 		t.Fatal(err)