Duck typing magic

config/config.go

@@ -30,7 +30,6 @@ import (
 	"github.com/opentracing/opentracing-go"
 
 	"github.com/uber/jaeger-client-go"
-	"github.com/uber/jaeger-client-go/log"
 	"github.com/uber/jaeger-client-go/transport"
 	"github.com/uber/jaeger-client-go/transport/udp"
 )
@@ -211,7 +210,7 @@ func (sc *SamplerConfig) NewSampler(
 func (rc *ReporterConfig) NewReporter(
 	serviceName string,
 	metrics *jaeger.Metrics,
-	logger log.Logger,
+	logger jaeger.Logger,
 ) (jaeger.Reporter, error) {
 	sender, err := rc.newTransport()
 	if err != nil {

config/options.go

@@ -24,7 +24,6 @@ import (
 	"github.com/uber/jaeger-lib/metrics"
 
 	"github.com/uber/jaeger-client-go"
-	"github.com/uber/jaeger-client-go/log"
 )
 
 // ClientOption is a function that sets some option on the client.
@@ -33,7 +32,7 @@ type ClientOption func(c *ClientOptions)
 // ClientOptions control behavior of the client.
 type ClientOptions struct {
 	metrics *jaeger.Metrics
-	logger  log.Logger
+	logger  jaeger.Logger
 }
 
 // Metrics creates a ClientOption that initializes Metrics in the client,
@@ -46,7 +45,7 @@ func Metrics(factory metrics.Factory) ClientOption {
 
 // Logger can be provided to log Reporter errors, as well as to log spans
 // if Reporter.LogSpans is set to true.
-func Logger(logger log.Logger) ClientOption {
+func Logger(logger jaeger.Logger) ClientOption {
 	return func(c *ClientOptions) {
 		c.logger = logger
 	}

logger.go

@@ -0,0 +1,59 @@
+// Copyright (c) 2016 Uber Technologies, Inc.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+package jaeger
+
+import "log"
+
+// NB This will be deprecated in 3.0.0, please use jaeger-client-go/log/logger instead.
+
+// Logger provides an abstract interface for logging from Reporters.
+// Applications can provide their own implementation of this interface to adapt
+// reporters logging to whatever logging library they prefer (stdlib log,
+// logrus, go-logging, etc).
+type Logger interface {
+	// Error logs a message at error priority
+	Error(msg string)
+
+	// Infof logs a message at info priority
+	Infof(msg string, args ...interface{})
+}
+
+// StdLogger is implementation of the Logger interface that delegates to default `log` package
+var StdLogger = &stdLogger{}
+
+type stdLogger struct{}
+
+func (l *stdLogger) Error(msg string) {
+	log.Printf("ERROR: %s", msg)
+}
+
+// Infof logs a message at info priority
+func (l *stdLogger) Infof(msg string, args ...interface{}) {
+	log.Printf(msg, args...)
+}
+
+// NullLogger is implementation of the Logger interface that delegates to default `log` package
+var NullLogger = &nullLogger{}
+
+type nullLogger struct{}
+
+func (l *nullLogger) Error(msg string)                      {}
+func (l *nullLogger) Infof(msg string, args ...interface{}) {}

logger_test.go

@@ -0,0 +1,32 @@
+// Copyright (c) 2017 Uber Technologies, Inc.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+package jaeger
+
+import (
+	"testing"
+)
+
+func TestLogger(t *testing.T) {
+	for _, logger := range []Logger{StdLogger, NullLogger} {
+		logger.Infof("Hi %s", "there")
+		logger.Error("Bad wolf")
+	}
+}