feat(internal/client): support dynamic log level

internal/client/client.go

@@ -10,6 +10,7 @@ import (
 	"io"
 	"log/slog"
 	"net"
+	"os"
 
 	"koti.casa/numenor-labs/dsfx/internal/lib/crypto/identity"
 	"koti.casa/numenor-labs/dsfx/internal/lib/disk"
@@ -28,6 +29,23 @@ const (
 type Conf struct {
 	// Directories
 	ConfigDir string
+	LogLevel  string
+}
+
+// SlogLevel returns the appropriate slog.Level based on the LogLevel string.
+func (c Conf) SlogLevel() slog.Level {
+	switch c.LogLevel {
+	case "debug":
+		return slog.LevelDebug
+	case "info":
+		return slog.LevelInfo
+	case "warn":
+		return slog.LevelWarn
+	case "error":
+		return slog.LevelError
+	default:
+		return slog.LevelInfo
+	}
 }
 
 func loadConfigFromSystem(sys system.System) Conf {
@@ -38,6 +56,9 @@ func loadConfigFromSystem(sys system.System) Conf {
 		c.ConfigDir = DefaultConfigDir
 	}
 
+	// defaults are handled by Conf.SlogLevel.
+	c.LogLevel = sys.GetEnv("DSFXCTL_LOG_LEVEL")
+
 	return c
 }
 
@@ -75,7 +96,7 @@ func (a *Client) Run(ctx context.Context) error {
 
 	opts := &slog.HandlerOptions{
 		AddSource: false,
-		Level:     slog.LevelInfo,
+		Level:     a.conf.SlogLevel(),
 	}
 	logger := slog.New(slog.NewTextHandler(a.system.Stdout(), opts))
 
@@ -114,13 +135,16 @@ func (a *Client) Run(ctx context.Context) error {
 			return err
 		}
 		testConnection(ctx, id, laddr, raddrRaw)
+		return nil
+	case "identity":
+		pubKey := identity.ToPublicKey(id)
+		logger.InfoContext(ctx, "identity", slog.String("publicKey", base64.StdEncoding.EncodeToString(pubKey)))
+		return nil
 	case "":
 		return errors.New("no command provided")
 	default:
 		return errors.New("unknown command: " + a.system.Arg(0))
 	}
-
-	return nil
 }
 
 func testConnection(ctx context.Context, id ed25519.PrivateKey, laddr *network.Addr, raddrRaw string) {
@@ -138,6 +162,8 @@ func testConnection(ctx context.Context, id ed25519.PrivateKey, laddr *network.A
 		return
 	}
 	defer conn.Close()
+
+	logger.InfoContext(ctx, "connected to server", slog.String("remote", raddr.String()))
 }
 
 // loadIdentity ...
@@ -159,6 +185,9 @@ func (c *Client) loadIdentity() (ed25519.PrivateKey, error) {
 // hasKeyFile ...
 func (c *Client) hasKeyFile() (bool, error) {
 	f, err := c.configScope.Open("ed25519.key")
+	if errors.Is(err, os.ErrNotExist) {
+		return false, nil // Key file does not exist
+	}
 	if err != nil {
 		return false, nil
 	}