Refactoring

- logging interface
- log levels
- application interface

Signed-off-by: Jan Tytgat <jan.tytgat@corelayer.eu>

application/application.go

@@ -2,15 +2,17 @@ package application
 
 import (
 	"context"
+	"errors"
 	"fmt"
+	"log/slog"
 	"os/signal"
 
+	"git.flexabyte.io/flexabyte/go-slogd/slogd"
 	"github.com/spf13/cobra"
 )
 
 type Application interface {
-	Start(ctx context.Context) error
+	ExecuteContext(ctx context.Context) error
-	Shutdown() error
 }
 
 func New(c Config) (Application, error) {
@@ -31,53 +33,67 @@ type application struct {
 	config Config
 }
 
-func (a *application) Start(ctx context.Context) error {
+func (a *application) ExecuteContext(ctx context.Context) error {
+	a.config.Logger.LogAttrs(ctx, slogd.LevelTrace, "configuring application shutdown signals", slog.Any("signals", a.config.ShutdownSignals))
 
-	sigCtx, sigStop := signal.NotifyContext(ctx, a.config.ShutdownSignals...)
+	sigCtx, sigCancel := signal.NotifyContext(ctx, a.config.ShutdownSignals...)
-	defer sigStop() // Ensure that this gets called.
+	defer sigCancel() // Ensure that this gets called.
 
-	// Result channel for command
+	// Result channel for command output
 	chExe := make(chan error)
-	go a.execute(sigCtx, chExe)
 
+	// Run the application command
+	a.config.Logger.LogAttrs(ctx, slogd.LevelTrace, "executing application context")
+	go func(ctx context.Context, chErr chan error) {
+		chErr <- a.cmd.ExecuteContext(ctx)
+	}(sigCtx, chExe)
+
+	// Wait for command output or a shutdown signal
+	var err error
 	select {
-	// sigCtx.Done() returns a channel that will have a message
+	// sigCtx.Done() returns a channel that will have a message when the context is canceled.
-	// when the context is cancelled. We wait for that signal, which means
+	// Alternatively, chExe will receive the response from the execution context if the application finishes.
-	// we received the signal, or our context was cancelled for some other reason.
 	case <-sigCtx.Done():
-		sigStop()
+		sigCancel()
-		return a.Shutdown()
+
-	case err := <-chExe:
+		// Adapt the shutdown scenario if a graceful shutdown period is configured
+		switch a.config.EnableGracefulShutdown && a.config.ShutdownTimeout > 0 {
+		case true:
+			a.config.Logger.LogAttrs(ctx, slogd.LevelTrace, "gracefully shutting down application")
+			if err = a.gracefulShutdown(ctx); !errors.Is(err, context.DeadlineExceeded) {
+				a.config.Logger.LogAttrs(ctx, slogd.LevelTrace, "graceful shutdown completed with error", slog.Any("error", err))
+				return err
+			}
+			a.config.Logger.LogAttrs(ctx, slogd.LevelTrace, "graceful shutdown completed")
+			return nil
+		case false:
+			a.config.Logger.LogAttrs(ctx, slogd.LevelTrace, "immediately shutting down application")
+			return nil
+		}
+	case err = <-chExe:
+		a.config.Logger.LogAttrs(ctx, slogd.LevelTrace, "application terminated successfully")
 		return err
 	}
-}
 
-func (a *application) Shutdown() error {
+	a.config.Logger.LogAttrs(ctx, slogd.LevelTrace, "application terminated unexpectedly")
-	switch a.config.EnableGracefulShutdown {
-	case true:
-		return a.gracefulShutdown()
-	case false:
-		return a.shutdown()
-		// default:
-		// 	return a.shutdown()
-	}
 	return nil
 }
 
-func (a *application) execute(ctx context.Context, chErr chan error) {
+func (a *application) gracefulShutdown(ctx context.Context) error {
-	chErr <- a.cmd.ExecuteContext(ctx)
+	fmt.Printf("waiting %s for graceful application shutdown... PRESS CTRL+C again to quit now!\n", a.config.ShutdownTimeout)
-}
 
-func (a *application) gracefulShutdown() error {
+	shutdownCtx, shutdownCancel := context.WithTimeout(ctx, a.config.ShutdownTimeout)
-	fmt.Println("graceful shutdown")
-
-	shutdownCtx, shutdownCancel := context.WithTimeout(context.Background(), a.config.ShutdownTimeout)
 	defer shutdownCancel()
-	<-shutdownCtx.Done()
-	return nil
-}
 
-func (a *application) shutdown() error {
+	// Wait for the shutdown timeout or a hard exit signal
-	fmt.Println("shutdown")
+	sigCtx, sigCancel := signal.NotifyContext(shutdownCtx, a.config.ShutdownSignals...)
-	return nil
+	defer sigCancel() // Ensure that this gets called.
+
+	select {
+	case <-shutdownCtx.Done():
+		return shutdownCtx.Err()
+	case <-sigCtx.Done():
+		sigCancel()
+		return nil
+	}
 }

application/config.go

@@ -3,6 +3,7 @@ package application
 import (
 	"errors"
 	"fmt"
+	"log/slog"
 	"os"
 	"time"
 
@@ -15,8 +16,9 @@ type Config struct {
 	Name                     string
 	Title                    string
 	Banner                   string
-	Version                  string
+	Version                  Version
 	EnableGracefulShutdown   bool
+	Logger                   *slog.Logger
 	OverrideRunE             func(cmd *cobra.Command, args []string) error
 	PersistentPreRunE        []func(cmd *cobra.Command, args []string) error // collection of PreRunE functions
 	PersistentPostRunE       []func(cmd *cobra.Command, args []string) error // collection of PostRunE functions
@@ -59,12 +61,7 @@ func (c Config) getRootCommand() (*cobra.Command, error) {
 		cmd.AddCommand(subcommand.Initialize(c.SubCommandInitializeFunc))
 	}
 
-	var v semver.Version
+	configureVersionFlag(cmd, c.Version)                  // Configure app for version information
-	if v, err = c.ParseVersion(); err != nil {
-		return nil, err
-	}
-
-	configureVersionFlag(cmd, v)                          // Configure app for version information
 	configureOutputFlags(cmd)                             // Configure verbosity
 	configureLoggingFlags(cmd)                            // Configure logging
 	cmd.PersistentFlags().SetNormalizeFunc(normalizeFunc) // normalize persistent flags
@@ -73,7 +70,7 @@ func (c Config) getRootCommand() (*cobra.Command, error) {
 }
 
 func (c Config) ParseVersion() (semver.Version, error) {
-	return semver.Parse(c.Version)
+	return semver.Parse(c.Version.Full)
 }
 
 func (c Config) RegisterCommand(cmd Commander, f func(*cobra.Command)) {
@@ -103,7 +100,7 @@ func (c Config) Validate() error {
 	}
 
 	var err error
-	if _, err = semver.Parse(c.Version); err != nil {
+	if _, err = semver.Parse(c.Version.Full); err != nil {
 		return fmt.Errorf("invalid version: %s", c.Version)
 	}
 	return nil

application/globals.go

@@ -66,7 +66,7 @@ func persistentPreRunFuncE(cmd *cobra.Command, args []string) error {
 
 	// TODO move to front??
 	if quietFlag {
-		slogd.FromContext(cmd.Context()).LogAttrs(cmd.Context(), slogd.LevelDebug, "activating quiet mode")
+		slogd.FromContext(cmd.Context()).LogAttrs(cmd.Context(), slogd.LevelTrace, "activating quiet mode")
 		outWriter = io.Discard
 	}
 

application/logging.go

@@ -1,6 +1,9 @@
 package application
 
 import (
+	"log/slog"
+
+	"git.flexabyte.io/flexabyte/go-slogd/slogd"
 	"github.com/spf13/cobra"
 )
 
@@ -10,20 +13,25 @@ const (
 	LogOutputFile   = "file"
 )
 
-var logLevelFlag string
+var (
-var logOutputFlag string
+	logLevelFlagName  string = "log-level"
-var logTypeFlag string
+	logLevelFlag      string
+	logOutputFlagName string = "log-output"
+	logOutputFlag     string
+	logTypeFlagName   = "log-type"
+	logTypeFlag       string
+)
 
 func addLogLevelFlag(cmd *cobra.Command) {
-	cmd.PersistentFlags().StringVarP(&logLevelFlag, "log-level", "", "info", "Set log level (trace, debug, info, warn, error, fatal)")
+	cmd.PersistentFlags().StringVarP(&logLevelFlag, logLevelFlagName, "", "info", "Set log level (trace, debug, info, warn, error, fatal)")
 }
 
 func addLogOutputFlag(cmd *cobra.Command) {
-	cmd.PersistentFlags().StringVarP(&logOutputFlag, "log-outWriter", "", "stderr", "Set log outWriter (stdout, stderr, file)")
+	cmd.PersistentFlags().StringVarP(&logOutputFlag, logOutputFlagName, "", "stderr", "Set log output (stdout, stderr, file)")
 }
 
 func addLogTypeFlag(cmd *cobra.Command) {
-	cmd.PersistentFlags().StringVarP(&logTypeFlag, "log-type", "", "text", "Set log type (text, json, color)")
+	cmd.PersistentFlags().StringVarP(&logTypeFlag, logTypeFlagName, "", "text", "Set log type (text, json, color)")
 }
 
 func configureLoggingFlags(cmd *cobra.Command) {
@@ -33,3 +41,12 @@ func configureLoggingFlags(cmd *cobra.Command) {
 
 	cmd.MarkFlagsMutuallyExclusive("no-color", "log-type")
 }
+
+func GetLogLevelFromArgs(args []string) slog.Level {
+	for i, arg := range args {
+		if arg == "--log-level" && i+1 < len(args) {
+			return slogd.Level(args[i+1])
+		}
+	}
+	return slogd.LevelDefault
+}

go.mod

@@ -3,7 +3,7 @@ module git.flexabyte.io/flexabyte/go-kit
 go 1.24.2
 
 require (
-	git.flexabyte.io/flexabyte/go-slogd v0.0.0-20250422113213-08cde7c3729c
+	git.flexabyte.io/flexabyte/go-slogd v0.0.0-20250428200220-8e65f81d9450
 	github.com/spf13/cobra v1.9.1
 	github.com/spf13/pflag v1.0.6
 )

go.sum

@@ -2,6 +2,8 @@ git.flexabyte.io/flexabyte/go-slogd v0.0.0-20250416190113-64c1cac4d274 h1:aR9nV8
 git.flexabyte.io/flexabyte/go-slogd v0.0.0-20250416190113-64c1cac4d274/go.mod h1:rL08OHw4aycfjkZOS8pBfLapeG3IZHxIInW29hVVSrI=
 git.flexabyte.io/flexabyte/go-slogd v0.0.0-20250422113213-08cde7c3729c h1:8ZVNJJ/LNbu4aWozJ6wj0ZOZFeuqRh1xSyQRh+Cq1yM=
 git.flexabyte.io/flexabyte/go-slogd v0.0.0-20250422113213-08cde7c3729c/go.mod h1:rL08OHw4aycfjkZOS8pBfLapeG3IZHxIInW29hVVSrI=
+git.flexabyte.io/flexabyte/go-slogd v0.0.0-20250428200220-8e65f81d9450 h1:VCstITW9pMgR5EnSLU83UiK7llLOguFLAo26VOOnzrI=
+git.flexabyte.io/flexabyte/go-slogd v0.0.0-20250428200220-8e65f81d9450/go.mod h1:rL08OHw4aycfjkZOS8pBfLapeG3IZHxIInW29hVVSrI=
 github.com/cpuguy83/go-md2man/v2 v2.0.6/go.mod h1:oOW0eioCTA6cOiMLiUPZOpcVxMig6NIQQ7OS05n1F4g=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=