Add logging

cmd/example.go

@@ -3,6 +3,7 @@ package cmd
 import (
 	"bytes"
 	"fmt"
+	"log/slog"
 
 	"github.com/spf13/cobra"
 	"github.com/yuin/goldmark"
@@ -27,6 +28,8 @@ var exampleCmd = &cobra.Command{
 
 		fmt.Println(buf.String())
 
+		slog.Info("This is a log message")
+
 		return nil
 	},
 }

cmd/root.go

@@ -2,16 +2,96 @@ package cmd
 
 import (
 	"fmt"
+	"log/slog"
 	"os"
+	"strings"
+	"time"
 
+	"github.com/lmittmann/tint"
 	"github.com/spf13/cobra"
+	"golang.org/x/term"
 )
 
+var logLevelString string
+var enableRichLogs bool
+var disableRichLogs bool
+
 var rootCmd = &cobra.Command{
 	Use: "almanac",
 	// TODO: Add description
 }
 
+func init() {
+	rootCmd.PersistentFlags().StringVar(&logLevelString, "log-level", "info", "Log level (debug, info, warn, error)")
+	_ = rootCmd.RegisterFlagCompletionFunc(
+		"log-level",
+		func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
+			var matching []string
+
+			for _, level := range []string{"debug", "info", "warn", "error"} {
+				if strings.HasPrefix(level, toComplete) {
+					matching = append(matching, level)
+				}
+			}
+
+			return matching, cobra.ShellCompDirectiveNoFileComp
+		},
+	)
+
+	rootCmd.PersistentFlags().BoolVar(
+		&enableRichLogs,
+		"enable-rich-logs",
+		false,
+		"Enable rich logs, even in non-terminal environments",
+	)
+	rootCmd.PersistentFlags().BoolVar(
+		&disableRichLogs,
+		"disable-rich-logs",
+		false,
+		"Disable rich logs, even in terminal environments",
+	)
+
+	cobra.OnInitialize(setupLogging)
+}
+
+func setupLogging() {
+	level, validLevel := map[string]slog.Level{
+		"debug": slog.LevelDebug,
+		"info":  slog.LevelInfo,
+		"warn":  slog.LevelWarn,
+		"error": slog.LevelError,
+	}[strings.ToLower(logLevelString)]
+
+	if !validLevel {
+		slog.Error(
+			"Invalid log level",
+			"log-level", logLevelString,
+		)
+		os.Exit(1)
+	}
+
+	if (term.IsTerminal(int(os.Stderr.Fd())) && !disableRichLogs) || enableRichLogs {
+		slog.SetDefault(slog.New(
+			tint.NewHandler(
+				os.Stderr,
+				&tint.Options{
+					TimeFormat: time.Kitchen,
+					Level:      level,
+				},
+			),
+		))
+	} else {
+		slog.SetDefault(slog.New(
+			slog.NewJSONHandler(
+				os.Stderr,
+				&slog.HandlerOptions{
+					Level: level,
+				},
+			),
+		))
+	}
+}
+
 func Execute() {
 	if err := rootCmd.Execute(); err != nil {
 		_, _ = fmt.Fprintln(os.Stderr, err)

go.mod

@@ -3,11 +3,14 @@ module github.com/fogo-sh/almanac
 go 1.21.0
 
 require (
+	github.com/lmittmann/tint v1.0.0
 	github.com/spf13/cobra v1.7.0
 	github.com/yuin/goldmark v1.5.6
+	golang.org/x/term v0.11.0
 )
 
 require (
 	github.com/inconshreveable/mousetrap v1.1.0 // indirect
 	github.com/spf13/pflag v1.0.5 // indirect
+	golang.org/x/sys v0.11.0 // indirect
 )

go.sum

@@ -1,12 +1,18 @@
 github.com/cpuguy83/go-md2man/v2 v2.0.2/go.mod h1:tgQtvFlXSQOSOSIRvRPT7W67SCa46tRHOmNcaadrF8o=
 github.com/inconshreveable/mousetrap v1.1.0 h1:wN+x4NVGpMsO7ErUn/mUI3vEoE6Jt13X2s0bqwp9tc8=
 github.com/inconshreveable/mousetrap v1.1.0/go.mod h1:vpF70FUmC8bwa3OWnCshd2FqLfsEA9PFc4w1p2J65bw=
+github.com/lmittmann/tint v1.0.0 h1:fzEj70K1L58uyoePQxKe+ezDZJ5pybiWGdA0JeFvvyw=
+github.com/lmittmann/tint v1.0.0/go.mod h1:HIS3gSy7qNwGCj+5oRjAutErFBl4BzdQP6cJZ0NfMwE=
 github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
 github.com/spf13/cobra v1.7.0 h1:hyqWnYt1ZQShIddO5kBpj3vu05/++x6tJ6dg8EC572I=
 github.com/spf13/cobra v1.7.0/go.mod h1:uLxZILRyS/50WlhOIKD7W6V5bgeIt+4sICxh6uRMrb0=
 github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
 github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
 github.com/yuin/goldmark v1.5.6 h1:COmQAWTCcGetChm3Ig7G/t8AFAN00t+o8Mt4cf7JpwA=
 github.com/yuin/goldmark v1.5.6/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
+golang.org/x/sys v0.11.0 h1:eG7RXZHdqOJ1i+0lgLgCpSXAp6M3LYlAo6osgSi0xOM=
+golang.org/x/sys v0.11.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/term v0.11.0 h1:F9tnn/DA/Im8nCwm+fX+1/eBwi4qFjRT++MhtVC4ZX0=
+golang.org/x/term v0.11.0/go.mod h1:zC9APTIj3jG3FdV/Ons+XE1riIZXG4aZ4GTHiPZJPIU=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=