feat: logger - add new options (#3)

Reviewed-on: twhelp/corev3#3

cmd/twhelp/app.go

@@ -7,17 +7,23 @@ import (
 	"github.com/urfave/cli/v2"
 )
 
+type appMode string
+
 const (
-	appModeProduction  = "production"
-	appModeDevelopment = "development"
+	appModeProduction  appMode = "production"
+	appModeDevelopment appMode = "development"
 )
 
+func (m appMode) String() string {
+	return string(m)
+}
+
 var (
 	appFlagMode = &cli.GenericFlag{
 		Name: "mode",
 		Value: &EnumValue{
-			Enum:    []string{appModeDevelopment, appModeProduction},
-			Default: appModeDevelopment,
+			Enum:    []string{appModeDevelopment.String(), appModeProduction.String()},
+			Default: appModeDevelopment.String(),
 		},
 		Usage:   fmt.Sprintf("%s or %s", appModeProduction, appModeDevelopment),
 		EnvVars: []string{"APP_MODE"},
@@ -38,12 +44,14 @@ func newApp(name, version string) *appWrapper {
 	app.HelpName = name
 	app.Version = version
 	app.Commands = []*cli.Command{cmdDB, cmdJob}
-	app.Flags = appFlags
+	app.Flags = concatSlices(appFlags, logFlags)
 	app.Before = app.handleBefore
 	return app
 }
 
 func (a *appWrapper) handleBefore(c *cli.Context) error {
+	a.logger = newLoggerFromFlags(c)
+
 	c.Context = loggerToCtx(c.Context, a.logger)
 
 	a.logger.Debug("executing command", slog.Any("args", c.Args().Slice()))

cmd/twhelp/logger.go

@@ -2,9 +2,115 @@ package main
 
 import (
 	"context"
+	"fmt"
+	"io"
 	"log/slog"
+	"os"
+
+	"github.com/urfave/cli/v2"
 )
 
+type logLevel string
+
+const (
+	logLevelDebug logLevel = "debug"
+	logLevelInfo  logLevel = "info"
+	logLevelWarn  logLevel = "warn"
+	logLevelError logLevel = "error"
+)
+
+func (l logLevel) slogLevel() slog.Level {
+	switch l {
+	case logLevelDebug:
+		return slog.LevelDebug
+	case logLevelInfo:
+		return slog.LevelInfo
+	case logLevelWarn:
+		return slog.LevelWarn
+	case logLevelError:
+		return slog.LevelError
+	default:
+		panic("unknown log level: " + l)
+	}
+}
+
+func (l logLevel) String() string {
+	return string(l)
+}
+
+type logFormat string
+
+const (
+	logFormatText logFormat = "text"
+	logFormatJSON logFormat = "json"
+)
+
+func (f logFormat) newHandler(w io.Writer, opts *slog.HandlerOptions) slog.Handler {
+	switch f {
+	case logFormatText:
+		return slog.NewTextHandler(w, opts)
+	case logFormatJSON:
+		return slog.NewJSONHandler(w, opts)
+	default:
+		panic("unknown log format: " + f)
+	}
+}
+
+func (f logFormat) String() string {
+	return string(f)
+}
+
+var (
+	logFlagLevel = &cli.GenericFlag{
+		Name: "log.level",
+		Value: &EnumValue{
+			Enum: []string{
+				logLevelDebug.String(),
+				logLevelInfo.String(),
+				logLevelWarn.String(),
+				logLevelError.String(),
+			},
+			Default: logLevelInfo.String(),
+		},
+		Usage:   fmt.Sprintf("%s, %s, %s or %s", logLevelDebug, logLevelInfo, logLevelWarn, logLevelError),
+		EnvVars: []string{"LOG_LEVEL"},
+	}
+	logFlagFormat = &cli.GenericFlag{
+		Name: "log.format",
+		Value: &EnumValue{
+			Enum: []string{
+				logFormatJSON.String(),
+				logFormatText.String(),
+			},
+			Default: logFormatText.String(),
+		},
+		Usage:   fmt.Sprintf("%s or %s", logFormatText, logFormatJSON),
+		EnvVars: []string{"LOG_FORMAT"},
+	}
+	logFlags = []cli.Flag{
+		logFlagLevel,
+		logFlagFormat,
+	}
+)
+
+func newLoggerFromFlags(c *cli.Context) *slog.Logger {
+	return newLogger(loggerConfig{
+		level:  logLevel(c.String(logFlagLevel.Name)),
+		format: logFormat(c.String(logFlagFormat.Name)),
+	})
+}
+
+type loggerConfig struct {
+	level  logLevel
+	format logFormat
+}
+
+func newLogger(cfg loggerConfig) *slog.Logger {
+	return slog.New(cfg.format.newHandler(os.Stderr, &slog.HandlerOptions{
+		Level: cfg.level.slogLevel(),
+	}))
+}
+
 type loggerCtxKey struct{}
 
 func loggerToCtx(ctx context.Context, l *slog.Logger) context.Context {

k8s/base/jobs.yml

@@ -20,6 +20,8 @@ spec:
               env:
                 - name: APP_MODE
                   value: development
+                - name: LOG_LEVEL
+                  value: debug
                 - name: DB_CONNECTION_STRING
                   valueFrom:
                     secretKeyRef:
@@ -56,6 +58,8 @@ spec:
           env:
             - name: APP_MODE
               value: development
+            - name: LOG_LEVEL
+              value: debug
             - name: DB_CONNECTION_STRING
               valueFrom:
                 secretKeyRef: