Centralize lets log prefix and colorize debug output

docs/docs/changelog.md

@@ -16,6 +16,7 @@ title: Changelog
 * `[Refactoring]` Move CLI startup flow from `cmd/lets/main.go` into `internal/cli/cli.go`, keeping `main.go` as a thin launcher.
 * `[Added]` Add `lets self doc` command to open the online documentation in a browser.
 * `[Added]` Show background update notifications for interactive sessions, with Homebrew-aware guidance and `LETS_CHECK_UPDATE` opt-out.
+* `[Changed]` Centralize the `lets:` log prefix in the formatter and render debug messages in blue.
 
 ## [0.0.59](https://github.com/lets-cli/lets/releases/tag/v0.0.59)
 

internal/cli/cli.go

@@ -47,19 +47,19 @@ func Main(version string, buildDate string) int {
 
 	command, args, err := rootCmd.Traverse(os.Args[1:])
 	if err != nil {
-		log.Errorf("lets: traverse commands error: %s", err)
+		log.Errorf("traverse commands error: %s", err)
 		return getExitCode(err, 1)
 	}
 
 	rootFlags, err := parseRootFlags(args)
 	if err != nil {
-		log.Errorf("lets: parse flags error: %s", err)
+		log.Errorf("parse flags error: %s", err)
 		return 1
 	}
 
 	if rootFlags.version {
 		if err := cmd.PrintVersionMessage(rootCmd); err != nil {
-			log.Errorf("lets: print version error: %s", err)
+			log.Errorf("print version error: %s", err)
 			return 1
 		}
 
@@ -79,7 +79,7 @@ func Main(version string, buildDate string) int {
 	cfg, err := config.Load(rootFlags.config, configDir, version)
 	if err != nil {
 		if failOnConfigError(rootCmd, command, rootFlags) {
-			log.Errorf("lets: config error: %s", err)
+			log.Errorf("config error: %s", err)
 			return 1
 		}
 	}
@@ -96,7 +96,7 @@ func Main(version string, buildDate string) int {
 		}
 
 		if err != nil {
-			log.Errorf("lets: can not create lets.yaml: %s", err)
+			log.Errorf("can not create lets.yaml: %s", err)
 			return 1
 		}
 
@@ -110,7 +110,7 @@ func Main(version string, buildDate string) int {
 		}
 
 		if err != nil {
-			log.Errorf("lets: can not self-upgrade binary: %s", err)
+			log.Errorf("can not self-upgrade binary: %s", err)
 			return 1
 		}
 
@@ -121,7 +121,7 @@ func Main(version string, buildDate string) int {
 
 	if showUsage {
 		if err := cmd.PrintRootHelpMessage(rootCmd); err != nil {
-			log.Errorf("lets: print help error: %s", err)
+			log.Errorf("print help error: %s", err)
 			return 1
 		}
 
@@ -137,7 +137,7 @@ func Main(version string, buildDate string) int {
 			executor.PrintDependencyTree(depErr, os.Stderr)
 		}
 
-		log.Errorf("lets: %s", err.Error())
+		log.Errorf("%s", err.Error())
 
 		return getExitCode(err, 1)
 	}
@@ -161,7 +161,7 @@ func getContext() context.Context {
 
 	go func() {
 		sig := <-ch
-		log.Printf("lets: signal received: %s", sig)
+		log.Printf("signal received: %s", sig)
 		cancel()
 	}()
 
@@ -211,7 +211,7 @@ func maybeStartUpdateCheck(
 		return nil, func() {}
 	}
 
-	log.Debugf("lets: start update check")
+	log.Debugf("start update check")
 
 	notifier, err := upgrade.NewUpdateNotifier(registry.NewGithubRegistry())
 	if err != nil {
@@ -227,7 +227,7 @@ func maybeStartUpdateCheck(
 			upgrade.LogUpdateCheckError(err)
 		}
 
-		log.Debugf("lets: update check done")
+		log.Debugf("update check done")
 
 		ch <- updateCheckResult{
 			notifier: notifier,

internal/config/config/command.go

@@ -162,7 +162,7 @@ func (c *Command) GetEnv(cfg Config, builtinEnv map[string]string) (map[string]s
 
 	envFileEnv, err := envFiles.Load(cfg, filenameEnv)
 	if err != nil {
-		return nil, fmt.Errorf("lets: failed to resolve env_file for command '%s': %w", c.Name, err)
+		return nil, fmt.Errorf("failed to resolve env_file for command '%s': %w", c.Name, err)
 	}
 
 	resolvedEnv := envs.Dump()

internal/config/find.go

@@ -4,7 +4,6 @@ import (
 	"fmt"
 	"path/filepath"
 
-	"github.com/fatih/color"
 	"github.com/lets-cli/lets/internal/config/path"
 	"github.com/lets-cli/lets/internal/util"
 	"github.com/lets-cli/lets/internal/workdir"
@@ -39,7 +38,7 @@ func FindConfig(configName string, configDir string) (PathInfo, error) {
 		return PathInfo{}, err
 	}
 
-	log.Debugf("%s", color.BlueString("lets: found %s config file in %s directory", configName, workDir))
+	log.Debugf("found %s config file in %s directory", configName, workDir)
 
 	configAbsPath := ""
 

internal/logging/formatter.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"strings"
 
+	"github.com/fatih/color"
 	log "github.com/sirupsen/logrus"
 )
 
@@ -20,13 +21,36 @@ type Formatter struct{}
 // Format implements the log.Formatter interface.
 func (f *Formatter) Format(entry *log.Entry) ([]byte, error) {
 	buff := &bytes.Buffer{}
-	buff.WriteString(writeData(entry.Data))
-	buff.WriteString(entry.Message)
+	parts := []string{formatPrefix(entry)}
+
+	if data := writeData(entry.Data); data != "" {
+		parts = append(parts, data)
+	}
+
+	parts = append(parts, formatMessage(entry))
+
+	buff.WriteString(strings.Join(parts, " "))
 	buff.WriteString("\n")
 
 	return buff.Bytes(), nil
 }
 
+func formatPrefix(entry *log.Entry) string {
+	if entry.Level == log.DebugLevel {
+		return color.BlueString("lets:")
+	}
+
+	return "lets:"
+}
+
+func formatMessage(entry *log.Entry) string {
+	if entry.Level == log.DebugLevel {
+		return color.BlueString(entry.Message)
+	}
+
+	return entry.Message
+}
+
 func writeData(fields log.Fields) string {
 	var buff []string
 
@@ -39,9 +63,5 @@ func writeData(fields log.Fields) string {
 		}
 	}
 
-	if len(buff) > 0 {
-		buff = append(buff, "")
-	}
-
 	return strings.Join(buff, " ")
 }

internal/logging/log.go

@@ -41,21 +41,20 @@ func InitLogging(
 
 // ExecLogger is used in Executor.
 // If adds command chain in message like this:
-// lets: [foo=>bar] message.
+// [foo=>bar] message.
 type ExecLogger struct {
 	log *log.Logger
 	// command name
 	name string
-	// lets: [a=>b]
+	// [a=>b]
 	prefix string
 	cache  map[string]*ExecLogger
 }
 
 func NewExecLogger() *ExecLogger {
 	return &ExecLogger{
-		log:    log.StandardLogger(),
-		prefix: color.BlueString("lets:"),
-		cache:  make(map[string]*ExecLogger),
+		log:   log.StandardLogger(),
+		cache: make(map[string]*ExecLogger),
 	}
 }
 
@@ -71,19 +70,25 @@ func (l *ExecLogger) Child(name string) *ExecLogger {
 	l.cache[name] = &ExecLogger{
 		log:    l.log,
 		name:   name,
-		prefix: color.BlueString("lets: %s", color.GreenString("[%s]", name)),
+		prefix: color.GreenString("[%s]", name),
 		cache:  make(map[string]*ExecLogger),
 	}
 
 	return l.cache[name]
 }
 
 func (l *ExecLogger) Info(format string, a ...any) {
-	format = fmt.Sprintf("%s %s", l.prefix, color.BlueString(format))
+	if l.prefix != "" {
+		format = fmt.Sprintf("%s %s", l.prefix, format)
+	}
+
 	l.log.Logf(log.InfoLevel, format, a...)
 }
 
 func (l *ExecLogger) Debug(format string, a ...any) {
-	format = fmt.Sprintf("%s %s", l.prefix, color.BlueString(format))
+	if l.prefix != "" {
+		format = fmt.Sprintf("%s %s", l.prefix, format)
+	}
+
 	l.log.Logf(log.DebugLevel, format, a...)
 }