Update logger to facilitate the use of global logger

Makefile

@@ -47,6 +47,12 @@ check-modtidy:
 	go mod tidy
 	git diff --exit-code -- go.mod go.sum
 
+fmt:
+	gofmt -l -s -w .
+
+vet:
+	go vet ./...
+
 lint:
 	golangci-lint --version
 	golangci-lint run

cmd/demo-cli/main.go

@@ -13,6 +13,7 @@ func main() {
 		EnvPrefix:   "golem",
 		GitVersion:  version.GitVersion,
 		GitRevision: version.GitRevision,
+		LogLevel:    "debug"
 	}
 
 	// Define application level features

pkg/cli/config.go

@@ -1,7 +1,6 @@
 package cli
 
 import (
-	"context"
 	"fmt"
 	"github.com/zondax/golem/pkg/logger"
 	"strings"
@@ -15,7 +14,7 @@ func SetupConfiguration(c *cobra.Command) {
 	c.PersistentFlags().StringVarP(&configFileFlag, "config", "c", "", "The path to the config file to use.")
 	err := viper.BindPFlag("config", c.PersistentFlags().Lookup("config"))
 	if err != nil {
-		logger.GetLoggerFromContext(context.Background()).Fatalf("unable to bind config flag: %+v", err)
+		logger.Fatalf("unable to bind config flag: %+v", err)
 	}
 
 	viper.SetConfigName("config") // config file name without extension
@@ -50,12 +49,12 @@ func LoadConfig[T Config]() (*T, error) {
 	configFileOverride := viper.GetString("config")
 	if configFileOverride != "" {
 		viper.SetConfigFile(configFileOverride)
-		logger.GetLoggerFromContext(context.Background()).Infof("Using config file: %s", viper.ConfigFileUsed())
+		logger.Infof("Using config file: %s", viper.ConfigFileUsed())
 	}
 
 	err = viper.ReadInConfig()
 	if err != nil {
-		logger.GetLoggerFromContext(context.Background()).Fatalf("%+v", err)
+		logger.Fatalf("%+v", err)
 	}
 
 	// adds all default+configFile values in viper to struct

pkg/cli/handlers.go

@@ -1,11 +1,11 @@
 package cli
 
 import (
-	"context"
-	"github.com/zondax/golem/pkg/logger"
 	"os"
 	"os/signal"
 	"syscall"
+
+	"github.com/zondax/golem/pkg/logger"
 )
 
 var defaultConfigHandler DefaultConfigHandler
@@ -15,13 +15,13 @@ func setupCloseHandler(handler CleanUpHandler) {
 	signal.Notify(c, os.Interrupt, syscall.SIGTERM)
 	go func() {
 		<-c
-		logger.GetLoggerFromContext(context.Background()).Warn("\r- Ctrl+C pressed in Terminal")
+		logger.Warn("\r- Ctrl+C pressed in Terminal")
 
 		if handler != nil {
 			handler()
 		}
 
-		_ = logger.Sync() // Sync logger
+		logger.Sync() // Sync logger
 		// TODO: friendly closing callback
 		os.Exit(0)
 	}()

pkg/cli/root.go

@@ -2,11 +2,11 @@ package cli
 
 import (
 	"fmt"
+	"os"
+
 	"github.com/spf13/cobra"
 	"github.com/spf13/viper"
-	"github.com/zondax/golem/pkg/constants"
 	"github.com/zondax/golem/pkg/logger"
-	"os"
 )
 
 type AppSettings struct {
@@ -16,6 +16,7 @@ type AppSettings struct {
 	EnvPrefix   string // environment variable MYAPP_.....
 	GitVersion  string
 	GitRevision string
+	LogLevel    string // Global log level for the app
 }
 
 type CLI struct {
@@ -50,9 +51,9 @@ func (c *CLI) init() {
 		Run: func(cmd *cobra.Command, args []string) {
 			err := c.checkConfig()
 			if err != nil {
-				fmt.Printf("%s\n", c.checkConfig().Error())
+				logger.Errorf("%s\n", c.checkConfig().Error())
 			} else {
-				fmt.Printf("Configuration OK\n")
+				logger.Infof("Configuration OK\n")
 			}
 		},
 	}
@@ -61,15 +62,18 @@ func (c *CLI) init() {
 		Use:   "version",
 		Short: "Print version",
 		Run: func(cmd *cobra.Command, args []string) {
-			fmt.Printf("%s\n", c.GetVersionString())
+			logger.Infof("%s\n", c.GetVersionString())
 		},
 	}
 
 	c.GetRoot().AddCommand(checkCmd)
 	c.GetRoot().AddCommand(versionCmd)
 
-	// TODO: We can make this optional? and more configurable if we see the need
-	logger.InitLogger(logger.Config{Level: constants.DebugLevel})
+	// If app log level is defined it is configued, logger.defaultConfig by default
+	if len(c.app.LogLevel) > 0 {
+		logger.InitLogger(logger.Config{Level: c.app.LogLevel})
+	}
+
 	setupCloseHandler(nil)
 	// Set Configuration Defaults
 	setupDefaultConfiguration(func() {
@@ -91,15 +95,12 @@ func (c *CLI) GetVersionString() string {
 
 func (c *CLI) Run() {
 	if err := c.rootCmd.Execute(); err != nil {
-		_, err := fmt.Fprintln(os.Stderr, err)
-		if err != nil {
-			return
-		}
-		_ = logger.Sync()
+		logger.Error(err.Error())
+		logger.Sync()
 		os.Exit(1)
 	}
 }
 
 func (c *CLI) Close() {
-	_ = logger.Sync()
+	logger.Sync()
 }

pkg/logger/README.md

@@ -0,0 +1,40 @@
+# logger package
+
+The logger package is intended to make unified log management in the whole app
+
+The log may be used in 2 ways:
+
+- Global: easy use of the global logger without the need to init or configure. 
+```
+package main
+
+import (
+    "github.com/zondax/golem/pkg/logger"
+)
+
+func main() {
+    // Importing logger global logger is configured in info level and may be used
+    logger.Info("Log info message")
+
+    // Reconfigure global logger with config
+    logger.SetGlobalConfig(logger.Config{Level: "debug"})
+    logger.Info("Log debug message")
+    logger.Sync()
+}
+```
+
+- Local: use distinct logger for the package
+```
+package main
+
+import (
+    "github.com/zondax/golem/pkg/logger"
+)
+
+func main() {
+    // Generate new logger with options and use it
+    log := logger.NewLogger(opts ...interface{})
+    log.Info("Log info message")
+    log.Sync()
+}
+```

pkg/logger/global.go

@@ -0,0 +1,88 @@
+package logger
+
+import (
+	"go.uber.org/zap"
+)
+
+func ReplaceGlobals(logger *zap.Logger) func() {
+	return zap.ReplaceGlobals(logger)
+}
+
+func SetGlobalConfig(config Config) func() {
+	logger := configureAndBuildLogger(config)
+	return ReplaceGlobals(logger)
+}
+
+func L() *zap.Logger {
+	return zap.L()
+}
+
+func S() *zap.SugaredLogger {
+	return zap.S()
+}
+
+func Info(msg string) {
+	L().Info(msg)
+}
+
+func Debug(msg string) {
+	L().Debug(msg)
+}
+
+func Warn(msg string) {
+	L().Warn(msg)
+}
+
+func Error(msg string) {
+	L().Error(msg)
+}
+
+func DPanic(msg string) {
+	L().DPanic(msg)
+}
+
+func Panic(msg string) {
+	L().Panic(msg)
+}
+
+func Fatal(msg string) {
+	L().Fatal(msg)
+}
+
+func Infof(template string, args ...interface{}) {
+	S().Infof(template, args...)
+}
+
+func Debugf(template string, args ...interface{}) {
+	S().Debugf(template, args...)
+}
+
+func Warnf(template string, args ...interface{}) {
+	S().Warnf(template, args...)
+}
+
+func Errorf(template string, args ...interface{}) {
+	S().Errorf(template, args...)
+}
+
+func DPanicf(template string, args ...interface{}) {
+	S().DPanicf(template, args...)
+}
+
+func Panicf(template string, args ...interface{}) {
+	S().Panicf(template, args...)
+}
+
+func Fatalf(template string, args ...interface{}) {
+	S().Fatalf(template, args...)
+}
+
+func Sync() error {
+	// Sync global logger
+	err := L().Sync()
+	if err != nil {
+		return err
+	}
+	// Sync global sugar logger
+	return S().Sync()
+}