#680 use a local logger type

util.go

@@ -12,6 +12,7 @@ package viper
 
 import (
 	"fmt"
+	"log"
 	"os"
 	"path/filepath"
 	"runtime"
@@ -217,3 +218,19 @@ func deepSearch(m map[string]interface{}, path []string) map[string]interface{}
 	}
 	return m
 }
+
+type logger struct{}
+
+func (logger) Tracef(f string, args ...interface{})   {}
+func (logger) Debugf(f string, args ...interface{})   {}
+func (logger) Infof(f string, args ...interface{})    {}
+func (logger) Warningf(f string, args ...interface{}) { log.Printf(f, args...) }
+func (logger) Errorf(f string, args ...interface{})   { log.Printf(f, args...) }
+func (logger) Fatalf(f string, args ...interface{})   { log.Fatalf(f, args...) }
+
+func (logger) Trace(args ...interface{})   {}
+func (logger) Debug(args ...interface{})   {}
+func (logger) Info(args ...interface{})    {}
+func (logger) Warning(args ...interface{}) { log.Print(args...) }
+func (logger) Error(args ...interface{})   { log.Print(args...) }
+func (logger) Fatal(args ...interface{})   { log.Fatal(args...) }

viper.go

@@ -40,13 +40,13 @@ import (
 	"github.com/magiconair/properties"
 	"github.com/mitchellh/mapstructure"
 	toml "github.com/pelletier/go-toml"
-	"github.com/sirupsen/logrus"
 	"github.com/spf13/afero"
 	"github.com/spf13/cast"
 	"github.com/spf13/pflag"
 )
 
-// Logger collects log messages.
+// Logger collects log messages. The default logger logs warnings,
+// errors and  fatals.
 var Logger interface {
 	Tracef(string, ...interface{})
 	Debugf(string, ...interface{})
@@ -61,7 +61,7 @@ var Logger interface {
 	Warning(...interface{})
 	Error(...interface{})
 	Fatal(...interface{})
-} = logrus.New()
+} = logger{}
 
 // ConfigMarshalError happens when failing to marshal the configuration.
 type ConfigMarshalError struct {