Fixes race, moved into global

internal/global/internal_logging.go

@@ -12,11 +12,12 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package debug // import "go.opentelemetry.io/otel/internal/debug"
+package global // import "go.opentelemetry.io/otel/internal/global"
 
 import (
 	"log"
 	"os"
+	"sync"
 
 	"github.com/go-logr/logr"
 	"github.com/go-logr/stdr"
@@ -26,28 +27,37 @@ import (
 //
 // The default logger uses stdr which is backed by the standard `log.Logger`
 // interface. This logger will only show messages at the Error Level.
-var globalLoggger logr.Logger = stdr.New(log.New(os.Stderr, "", log.LstdFlags|log.Lshortfile))
+var globalLoggerLock = &sync.RWMutex{}
+var globalLogger logr.Logger = stdr.New(log.New(os.Stderr, "", log.LstdFlags|log.Lshortfile))
 
 // SetLogger overrides the globalLogger with l.
 //
 // To see Info messages use a logger with `l.V(1).Enabled() == true`
 // To see Debug messages use a logger with `l.V(5).Enabled() == true`
 func SetLogger(l logr.Logger) {
-	globalLoggger = l
+	globalLoggerLock.Lock()
+	defer globalLoggerLock.Unlock()
+	globalLogger = l
 }
 
 // Info prints messages about the general state of the API or SDK.
 // This should usually be less then 5 messages a minute
 func Info(msg string, keysAndValues ...interface{}) {
-	globalLoggger.V(1).Info(msg, keysAndValues...)
+	globalLoggerLock.RLock()
+	defer globalLoggerLock.RUnlock()
+	globalLogger.V(1).Info(msg, keysAndValues...)
 }
 
 // Error prints messages about exceptional states of the API or SDK.
 func Error(err error, msg string, keysAndValues ...interface{}) {
-	globalLoggger.Error(err, msg, keysAndValues...)
+	globalLoggerLock.RLock()
+	defer globalLoggerLock.RUnlock()
+	globalLogger.Error(err, msg, keysAndValues...)
 }
 
 // Debug prints messages about all internal changes in the API or SDK.
 func Debug(msg string, keysAndValues ...interface{}) {
-	globalLoggger.V(5).Info(msg, keysAndValues...)
+	globalLoggerLock.RLock()
+	defer globalLoggerLock.RUnlock()
+	globalLogger.V(5).Info(msg, keysAndValues...)
 }

internal/global/internal_logging_test.go

@@ -12,7 +12,17 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-/*
-Package debug provides access to enable internal debugging of opentelemetry.
-*/
-package debug // import "go.opentelemetry.io/otel/internal/debug"
+package global
+
+import (
+	"log"
+	"os"
+	"testing"
+
+	"github.com/go-logr/stdr"
+)
+
+func TestRace(t *testing.T) {
+	go SetLogger(stdr.New(log.New(os.Stderr, "", 0)))
+	go Info("")
+}

internal_logging.go

@@ -17,10 +17,10 @@ package otel // import "go.opentelemetry.io/otel"
 import (
 	"github.com/go-logr/logr"
 
-	"go.opentelemetry.io/otel/internal/debug"
+	"go.opentelemetry.io/otel/internal/global"
 )
 
 // SetLogger configures the logger used internally to opentelemetry.
 func SetLogger(logger logr.Logger) {
-	debug.SetLogger(logger)
+	global.SetLogger(logger)
 }

internal_logging_test.go

@@ -0,0 +1,29 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package otel_test
+
+import (
+	"log"
+	"os"
+
+	"github.com/go-logr/stdr"
+
+	"go.opentelemetry.io/otel"
+)
+
+func ExampleSetLogger() {
+	logger := stdr.New(log.New(os.Stdout, "", log.LstdFlags|log.Lshortfile))
+	otel.SetLogger(logger)
+}

sdk/trace/batch_span_processor.go

@@ -22,7 +22,7 @@ import (
 	"time"
 
 	"go.opentelemetry.io/otel"
-	"go.opentelemetry.io/otel/internal/debug"
+	"go.opentelemetry.io/otel/internal/global"
 	"go.opentelemetry.io/otel/trace"
 )
 
@@ -238,7 +238,7 @@ func (bsp *batchSpanProcessor) exportSpans(ctx context.Context) error {
 	}
 
 	if l := len(bsp.batch); l > 0 {
-		debug.Info("exporting spans", "count", len(bsp.batch))
+		global.Info("exporting spans", "count", len(bsp.batch))
 		err := bsp.e.ExportSpans(ctx, bsp.batch)
 
 		// A new batch is always created after exporting, even if the batch failed to be exported.