[FAB-9975] logging: Docs and Examples

Change-Id: I22e58542d88cabf1b9b1111268155944eb882ce2
Signed-off-by: Firas Qutishat <firas.qutishat@securekey.com>

pkg/common/logging/example_test.go

@@ -0,0 +1,117 @@
+/*
+Copyright SecureKey Technologies Inc. All Rights Reserved.
+
+SPDX-License-Identifier: Apache-2.0
+*/
+package logging
+
+import (
+	"fmt"
+
+	"github.com/hyperledger/fabric-sdk-go/pkg/core/logging/testdata"
+)
+
+var modName = "module-xyz"
+
+func Example() {
+
+	Initialize(testdata.GetSampleLoggingProvider(&buf))
+	//Create new logger
+	logger := NewLogger(modName)
+
+	logger.Info("log test data")
+
+	fmt.Println("log info is completed")
+
+	// Output: log info is completed
+
+}
+
+func ExampleNewLogger() {
+
+	Initialize(testdata.GetSampleLoggingProvider(&buf))
+	//Create new logger
+	NewLogger(modName)
+
+	fmt.Println("log is completed")
+
+	// Output: log is completed
+
+}
+
+func ExampleInitialize() {
+
+	Initialize(testdata.GetSampleLoggingProvider(&buf))
+
+	fmt.Println("log is completed")
+
+	// Output: log is completed
+
+}
+
+func ExampleSetLevel() {
+
+	Initialize(testdata.GetSampleLoggingProvider(&buf))
+
+	SetLevel(modName, INFO)
+
+	fmt.Println("log is completed")
+
+	// Output: log is completed
+
+}
+
+func ExampleGetLevel() {
+
+	Initialize(testdata.GetSampleLoggingProvider(&buf))
+
+	SetLevel(modName, DEBUG)
+
+	l := GetLevel(modName)
+	if l != DEBUG {
+		fmt.Println("log level is not debug")
+		return
+	}
+
+	fmt.Println("log is completed")
+
+	// Output: log is completed
+
+}
+
+func ExampleIsEnabledFor() {
+
+	Initialize(testdata.GetSampleLoggingProvider(&buf))
+
+	isEnabled := IsEnabledFor(modName, DEBUG)
+
+	if !isEnabled {
+		fmt.Println("log level debug is enabled")
+		return
+	}
+
+	fmt.Println("log is completed")
+
+	// Output: log is completed
+
+}
+
+func ExampleLogLevel() {
+
+	Initialize(testdata.GetSampleLoggingProvider(&buf))
+
+	level, err := LogLevel("debug")
+	if err != nil {
+		fmt.Printf("failed LogLevel: %v", err)
+		return
+	}
+
+	if level != DEBUG {
+		fmt.Println("log level is not debug")
+		return
+	}
+	fmt.Println("log is completed")
+
+	// Output: log is completed
+
+}

pkg/common/logging/logger.go

@@ -4,6 +4,12 @@ Copyright SecureKey Technologies Inc. All Rights Reserved.
 SPDX-License-Identifier: Apache-2.0
 */
 
+// Package logging enables setting custom logger implementation.
+//
+//  Basic Flow:
+//  1) Initialize logger
+//  2) Create new logger for specific module
+//  3) Call log info
 package logging
 
 import (
@@ -80,21 +86,40 @@ func Initialize(l api.LoggerProvider) {
 }
 
 //SetLevel - setting log level for given module
+//  Parameters:
+//  module is module name
+//  level is logging level
 func SetLevel(module string, level Level) {
 	modlog.SetLevel(module, api.Level(level))
 }
 
 //GetLevel - getting log level for given module
+//  Parameters:
+//  module is module name
+//
+//  Returns:
+//  logging level
 func GetLevel(module string) Level {
 	return Level(modlog.GetLevel(module))
 }
 
 //IsEnabledFor - Check if given log level is enabled for given module
+//  Parameters:
+//  module is module name
+//  level is logging level
+//
+//  Returns:
+//  is logging enabled for this module and level
 func IsEnabledFor(module string, level Level) bool {
 	return modlog.IsEnabledFor(module, api.Level(level))
 }
 
 // LogLevel returns the log level from a string representation.
+//  Parameters:
+//  level is logging level in string representation
+//
+//  Returns:
+//  logging level
 func LogLevel(level string) (Level, error) {
 	l, err := metadata.ParseLevel(level)
 	return Level(l), err
@@ -211,14 +236,3 @@ func (l *Logger) logger() api.Logger {
 	})
 	return l.instance
 }
-
-// ParseLevel returns the log level from a string representation.
-func ParseLevel(level string) (Level, error) {
-	l, err := metadata.ParseLevel(level)
-	return Level(l), err
-}
-
-//ParseString returns String repressentation of given log level
-func ParseString(level Level) string {
-	return metadata.ParseString(api.Level(level))
-}