feat: Using logging module

README.md

@@ -104,3 +104,11 @@ That is why we use `cobra`.
 
 So for this project, we will use the combination of `pflag`, `viper` and
 `cobra`.
+
+### 2024/10/02
+
+#### Logging
+
+Use `zap` for logging system. Log will be output to stdout for dev purpose,
+but it is also output to files. The log files can then be fetched to
+`Elasticsearch` for analyzing.

configs/howmuch.yml

@@ -35,3 +35,14 @@ db:
   max-open-connections: 100
   # max connection life time
   max-connection-life-time: 10s
+
+log:
+  level: debug
+  development: true
+  disalbe-caller: false
+  disable-stacktrace: false
+  # console or json
+  format: console
+  output-paths:
+    - stdout
+    - /tmp/howmuch.log

go.mod

@@ -8,6 +8,7 @@ require (
 	github.com/spf13/cobra v1.8.1
 	github.com/spf13/viper v1.19.0
 	go.uber.org/automaxprocs v1.6.0
+	go.uber.org/zap v1.27.0
 )
 
 require (
@@ -41,8 +42,7 @@ require (
 	github.com/subosito/gotenv v1.6.0 // indirect
 	github.com/twitchyliquid64/golang-asm v0.15.1 // indirect
 	github.com/ugorji/go/codec v1.2.12 // indirect
-	go.uber.org/atomic v1.9.0 // indirect
-	go.uber.org/multierr v1.9.0 // indirect
+	go.uber.org/multierr v1.11.0 // indirect
 	golang.org/x/arch v0.8.0 // indirect
 	golang.org/x/crypto v0.23.0 // indirect
 	golang.org/x/exp v0.0.0-20230905200255-921286631fa9 // indirect

go.sum

@@ -105,12 +105,14 @@ github.com/twitchyliquid64/golang-asm v0.15.1 h1:SU5vSMR7hnwNxj24w34ZyCi/FmDZTkS
 github.com/twitchyliquid64/golang-asm v0.15.1/go.mod h1:a1lVb/DtPvCB8fslRZhAngC2+aY1QWCk3Cedj/Gdt08=
 github.com/ugorji/go/codec v1.2.12 h1:9LC83zGrHhuUA9l16C9AHXAqEV/2wBQ4nkvumAE65EE=
 github.com/ugorji/go/codec v1.2.12/go.mod h1:UNopzCgEMSXjBc6AOMqYvWC1ktqTAfzJZUZgYf6w6lg=
-go.uber.org/atomic v1.9.0 h1:ECmE8Bn/WFTYwEW/bpKD3M8VtR/zQVbavAoalC1PYyE=
-go.uber.org/atomic v1.9.0/go.mod h1:fEN4uk6kAWBTFdckzkM89CLk9XfWZrxpCo0nPH17wJc=
 go.uber.org/automaxprocs v1.6.0 h1:O3y2/QNTOdbF+e/dpXNNW7Rx2hZ4sTIPyybbxyNqTUs=
 go.uber.org/automaxprocs v1.6.0/go.mod h1:ifeIMSnPZuznNm6jmdzmU3/bfk01Fe2fotchwEFJ8r8=
-go.uber.org/multierr v1.9.0 h1:7fIwc/ZtS0q++VgcfqFDxSBZVv/Xo49/SYnDFupUwlI=
-go.uber.org/multierr v1.9.0/go.mod h1:X2jQV1h+kxSjClGpnseKVIxpmcjrj7MNnI0bnlfKTVQ=
+go.uber.org/goleak v1.3.0 h1:2K3zAYmnTNqV73imy9J1T3WC+gmCePx2hEGkimedGto=
+go.uber.org/goleak v1.3.0/go.mod h1:CoHD4mav9JJNrW/WLlf7HGZPjdw8EucARQHekz1X6bE=
+go.uber.org/multierr v1.11.0 h1:blXXJkSxSSfBVBlC76pxqeO+LN3aDfLQo+309xJstO0=
+go.uber.org/multierr v1.11.0/go.mod h1:20+QtiLqy0Nd6FdQB9TLXag12DsQkrbs3htMFfDN80Y=
+go.uber.org/zap v1.27.0 h1:aJMhYGrd5QSmlpLMr2MftRKl7t8J8PTZPA732ud/XR8=
+go.uber.org/zap v1.27.0/go.mod h1:GB2qFLM7cTU87MWRP2mPIjqfIDnGu+VIO4V/SdhGo2E=
 golang.org/x/arch v0.0.0-20210923205945-b76863e36670/go.mod h1:5om86z9Hs0C8fWVUuoMHwpExlXzs5Tkyp9hOrfG7pp8=
 golang.org/x/arch v0.8.0 h1:3wRIsP3pM4yUptoR96otTUOXI367OS0+c9eeRi9doIc=
 golang.org/x/arch v0.8.0/go.mod h1:FEVrYAQjsQXMVJ1nsMoVVXPZg6p2JE2mx8psSWTDQys=

internal/howmuch/helpers.go

@@ -23,11 +23,11 @@
 package howmuch
 
 import (
-	"fmt"
 	"os"
 	"path/filepath"
 	"strings"
 
+	"git.vinchent.xyz/vinchent/howmuch/internal/pkg/log"
 	"github.com/spf13/cobra"
 	"github.com/spf13/viper"
 )
@@ -64,8 +64,20 @@ func initConfig() {
 	viper.SetEnvKeyReplacer(replacer)
 
 	if err := viper.ReadInConfig(); err != nil {
-		fmt.Fprintln(os.Stderr, err)
+		log.ErrorLog("Failed to read viper configuration file", "err", err)
 	}
 
-	fmt.Fprintln(os.Stdout, "Using config file:", viper.ConfigFileUsed())
+	log.InfoLog("Using config file", "file", viper.ConfigFileUsed())
+}
+
+// logOptions set log options from the configs read by viper.
+func logOptions() *log.Options {
+	return &log.Options{
+		Level:             viper.GetString("log.level"),
+		Development:       viper.GetBool("log.development"),
+		DisableCaller:     viper.GetBool("log.disable-caller"),
+		DisableStacktrace: viper.GetBool("log.disable-stacktrace"),
+		Format:            viper.GetString("log.format"),
+		OutputPaths:       viper.GetStringSlice("log.output-paths"),
+	}
 }

internal/howmuch/howmuch.go

@@ -27,6 +27,7 @@ import (
 	"fmt"
 	"net/http"
 
+	"git.vinchent.xyz/vinchent/howmuch/internal/pkg/log"
 	"github.com/fsnotify/fsnotify"
 	"github.com/gin-gonic/gin"
 	"github.com/spf13/cobra"
@@ -47,6 +48,11 @@ func NewHowMuchCommand() *cobra.Command {
 		Long: `howmuch is a expense-sharing application that can help friends
 to share their expense of an event or a trip`,
 		RunE: func(cmd *cobra.Command, args []string) error {
+			// init log
+			log.Init(logOptions())
+			// Sync flush the buffer
+			defer log.Sync()
+
 			return run()
 		},
 		Args: func(cmd *cobra.Command, args []string) error {
@@ -76,18 +82,18 @@ to share their expense of an event or a trip`,
 }
 
 func run() error {
-	fmt.Println("How much do I owe you?")
+	log.DebugLog("How much do I owe you?")
 
 	settings, _ := json.MarshalIndent(viper.AllSettings(), "", "  ")
 
 	// watching reloading conf
 	viper.OnConfigChange(func(e fsnotify.Event) {
-		fmt.Println("Config file changed:", e.Name)
+		log.InfoLog("Config file changed:", e.Name)
 	})
 	viper.WatchConfig()
 
-	fmt.Println(string(settings))
-	fmt.Println(viper.GetString("db.username"))
+	log.InfoLog(string(settings))
+	log.InfoLog(viper.GetString("db.username"))
 
 	r := gin.Default()
 

internal/pkg/log/log.go

@@ -0,0 +1,157 @@
+// MIT License
+//
+// Copyright (c) 2024 vinchent <vinchent@vinchent.xyz>
+//
+// 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 log
+
+import (
+	"os"
+	"sync"
+
+	"go.uber.org/zap"
+	"go.uber.org/zap/zapcore"
+)
+
+type Logger interface {
+	FatalLog(msg string, keyValues ...interface{})
+	PanicLog(msg string, keyValues ...interface{})
+	ErrorLog(msg string, keyValues ...interface{})
+	WarnLog(msg string, keyValues ...interface{})
+	InfoLog(msg string, keyValues ...interface{})
+	DebugLog(msg string, keyValues ...interface{})
+	Sync()
+}
+
+// zapLogger is an implementation of Logger interface
+type zapLogger struct {
+	z *zap.Logger
+}
+
+var (
+	mu sync.Mutex
+
+	// default global logger
+	std = NewLogger(NewOptions())
+)
+
+// Init initializes global logger with options
+func Init(opts *Options) {
+	mu.Lock()
+	defer mu.Unlock()
+
+	std = NewLogger(opts)
+}
+
+func NewLogger(opts *Options) *zapLogger {
+	if opts == nil {
+		opts = NewOptions()
+	}
+
+	var zapLevel zapcore.Level
+	// If unknown level, use info
+	if err := zapLevel.UnmarshalText([]byte(opts.Level)); err != nil {
+		zapLevel = zap.InfoLevel
+	}
+
+	encoderCfg := zap.NewProductionEncoderConfig()
+	encoderCfg.TimeKey = "timestamp"
+	encoderCfg.MessageKey = "message"
+	encoderCfg.EncodeTime = zapcore.ISO8601TimeEncoder
+
+	config := zap.Config{
+		Level:             zap.NewAtomicLevelAt(zapLevel),
+		Development:       opts.Development,
+		DisableCaller:     opts.DisableCaller,
+		DisableStacktrace: opts.DisableStacktrace,
+		Sampling:          nil,
+		Encoding:          opts.Format,
+		EncoderConfig:     encoderCfg,
+		OutputPaths:       opts.OutputPaths,
+		ErrorOutputPaths: []string{
+			"stderr",
+		},
+		InitialFields: map[string]interface{}{
+			"pid": os.Getpid(),
+		},
+	}
+
+	z := zap.Must(config.Build(zap.AddStacktrace(zapcore.PanicLevel), zap.AddCallerSkip(1)))
+
+	zap.RedirectStdLog(z)
+
+	return &zapLogger{z: z}
+}
+
+func (z *zapLogger) FatalLog(msg string, keyValues ...interface{}) {
+	z.z.Sugar().Fatalw(msg, keyValues...)
+}
+
+func (z *zapLogger) PanicLog(msg string, keyValues ...interface{}) {
+	z.z.Sugar().Panicw(msg, keyValues...)
+}
+
+func (z *zapLogger) ErrorLog(msg string, keyValues ...interface{}) {
+	z.z.Sugar().Errorw(msg, keyValues...)
+}
+
+func (z *zapLogger) WarnLog(msg string, keyValues ...interface{}) {
+	z.z.Sugar().Warnw(msg, keyValues...)
+}
+
+func (z *zapLogger) InfoLog(msg string, keyValues ...interface{}) {
+	z.z.Sugar().Infow(msg, keyValues...)
+}
+
+func (z *zapLogger) DebugLog(msg string, keyValues ...interface{}) {
+	z.z.Sugar().Debugw(msg, keyValues...)
+}
+
+func (z *zapLogger) Sync() {
+	_ = z.z.Sync()
+}
+
+func FatalLog(msg string, keyValues ...interface{}) {
+	std.z.Sugar().Fatalw(msg, keyValues...)
+}
+
+func PanicLog(msg string, keyValues ...interface{}) {
+	std.z.Sugar().Panicw(msg, keyValues...)
+}
+
+func ErrorLog(msg string, keyValues ...interface{}) {
+	std.z.Sugar().Errorw(msg, keyValues...)
+}
+
+func WarnLog(msg string, keyValues ...interface{}) {
+	std.z.Sugar().Warnw(msg, keyValues...)
+}
+
+func InfoLog(msg string, keyValues ...interface{}) {
+	std.z.Sugar().Infow(msg, keyValues...)
+}
+
+func DebugLog(msg string, keyValues ...interface{}) {
+	std.z.Sugar().Debugw(msg, keyValues...)
+}
+
+func Sync() {
+	_ = std.z.Sync()
+}

internal/pkg/log/options.go

@@ -0,0 +1,46 @@
+// MIT License
+//
+// Copyright (c) 2024 vinchent <vinchent@vinchent.xyz>
+//
+// 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 log
+
+// Options define the logger options
+type Options struct {
+	Level             string
+	Development       bool
+	DisableCaller     bool
+	DisableStacktrace bool
+	Format            string
+	OutputPaths       []string
+}
+
+func NewOptions() *Options {
+	return &Options{
+		Level:             "debug",
+		Development:       true,
+		DisableCaller:     false,
+		DisableStacktrace: false,
+		Format:            "console",
+		OutputPaths: []string{
+			"stderr",
+		},
+	}
+}