Allow log level names to be overridden

go.mod

@@ -5,8 +5,8 @@ go 1.22.5
 require (
 	github.com/jackpal/gateway v1.0.15
 	github.com/pkg/term v1.1.0
-	golang.org/x/exp v0.0.0-20240707233637-46b078467d37
-	golang.org/x/image v0.18.0
+	golang.org/x/exp v0.0.0-20240909161429-701f63a606c0
+	golang.org/x/image v0.20.0
 	gopkg.in/yaml.v3 v3.0.1
 )
 
@@ -15,6 +15,6 @@ require (
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/stretchr/objx v0.5.2 // indirect
 	github.com/stretchr/testify v1.9.0 // indirect
-	golang.org/x/net v0.27.0 // indirect
-	golang.org/x/sys v0.22.0 // indirect
+	golang.org/x/net v0.29.0 // indirect
+	golang.org/x/sys v0.25.0 // indirect
 )

go.sum

@@ -10,15 +10,15 @@ github.com/stretchr/objx v0.5.2 h1:xuMeJ0Sdp5ZMRXx/aWO6RZxdr3beISkG5/G/aIRr3pY=
 github.com/stretchr/objx v0.5.2/go.mod h1:FRsXN1f5AsAjCGJKqEizvkpNtU+EGNCLh3NxZ/8L+MA=
 github.com/stretchr/testify v1.9.0 h1:HtqpIVDClZ4nwg75+f6Lvsy/wHu+3BoSGCbBAcpTsTg=
 github.com/stretchr/testify v1.9.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
-golang.org/x/exp v0.0.0-20240707233637-46b078467d37 h1:uLDX+AfeFCct3a2C7uIWBKMJIR3CJMhcgfrUAqjRK6w=
-golang.org/x/exp v0.0.0-20240707233637-46b078467d37/go.mod h1:M4RDyNAINzryxdtnbRXRL/OHtkFuWGRjvuhBJpk2IlY=
-golang.org/x/image v0.18.0 h1:jGzIakQa/ZXI1I0Fxvaa9W7yP25TqT6cHIHn+6CqvSQ=
-golang.org/x/image v0.18.0/go.mod h1:4yyo5vMFQjVjUcVk4jEQcU9MGy/rulF5WvUILseCM2E=
-golang.org/x/net v0.27.0 h1:5K3Njcw06/l2y9vpGCSdcxWOYHOUk3dVNGDXN+FvAys=
-golang.org/x/net v0.27.0/go.mod h1:dDi0PyhWNoiUOrAS8uXv/vnScO4wnHQO4mj9fn/RytE=
+golang.org/x/exp v0.0.0-20240909161429-701f63a606c0 h1:e66Fs6Z+fZTbFBAxKfP3PALWBtpfqks2bwGcexMxgtk=
+golang.org/x/exp v0.0.0-20240909161429-701f63a606c0/go.mod h1:2TbTHSBQa924w8M6Xs1QcRcFwyucIwBGpK1p2f1YFFY=
+golang.org/x/image v0.20.0 h1:7cVCUjQwfL18gyBJOmYvptfSHS8Fb3YUDtfLIZ7Nbpw=
+golang.org/x/image v0.20.0/go.mod h1:0a88To4CYVBAHp5FXJm8o7QbUl37Vd85ply1vyD8auM=
+golang.org/x/net v0.29.0 h1:5ORfpBpCs4HzDYoodCDBbwHzdR5UrLBZ3sOnUJmFoHo=
+golang.org/x/net v0.29.0/go.mod h1:gLkgy8jTGERgjzMic6DS9+SP0ajcu6Xu3Orq/SpETg0=
 golang.org/x/sys v0.0.0-20200909081042-eff7692f9009/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.22.0 h1:RI27ohtqKCnwULzJLqkv897zojh5/DwS/ENaMzUOaWI=
-golang.org/x/sys v0.22.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+golang.org/x/sys v0.25.0 h1:r+8e+loiHxRqhXVl6ML1nO3l1+oFoWbnlu2Ehimmi34=
+golang.org/x/sys v0.25.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=

log/tracelog/tracelog.go

@@ -29,6 +29,9 @@ var _ slog.Handler = &Handler{}
 type Config struct {
 	// Level is the minimum log level that will be emitted. Defaults to slog.LevelInfo if not set.
 	Level slog.Leveler
+	// LevelNames is an optional map of slog.Level to string that will be used to format the log level. If not set, the
+	// default slog level names will be used.
+	LevelNames map[slog.Level]string
 	// Sink is the io.Writer that will receive the formatted log output. Defaults to os.Stderr if not set.
 	Sink io.Writer
 	// BufferDepth greater than 0 will enable asynchronous delivery of log messages to the sink. When enabled, if there
@@ -55,11 +58,12 @@ func (c *Config) Normalize() {
 // not optimized for performance, as I expect those that need to run this is environments where that matters will use
 // one of the implementations provided by slog itself.
 type Handler struct {
-	level    slog.Leveler
-	delivery chan []byte
-	lock     *sync.Mutex
-	sink     io.Writer
-	list     []entry
+	level      slog.Leveler
+	levelNames map[slog.Level]string
+	delivery   chan []byte
+	lock       *sync.Mutex
+	sink       io.Writer
+	list       []entry
 }
 
 type entry struct {
@@ -74,9 +78,10 @@ func New(cfg *Config) *Handler {
 	}
 	cfg.Normalize()
 	h := Handler{
-		level: cfg.Level,
-		lock:  &sync.Mutex{},
-		sink:  cfg.Sink,
+		level:      cfg.Level,
+		levelNames: cfg.LevelNames,
+		lock:       &sync.Mutex{},
+		sink:       cfg.Sink,
 	}
 	if cfg.BufferDepth > 0 {
 		h.delivery = make(chan []byte, cfg.BufferDepth)
@@ -117,17 +122,21 @@ func (h *Handler) withGroupOrAttrs(ga entry) *Handler {
 // Handle implements slog.Handler.
 func (h *Handler) Handle(_ context.Context, r slog.Record) error { //nolint:gocritic // Must use defined API
 	var buffer bytes.Buffer
-	switch r.Level {
-	case slog.LevelDebug:
-		buffer.WriteString("DBG")
-	case slog.LevelInfo:
-		buffer.WriteString("INF")
-	case slog.LevelWarn:
-		buffer.WriteString("WRN")
-	case slog.LevelError:
-		buffer.WriteString("ERR")
-	default:
-		fmt.Fprintf(&buffer, "%3d", r.Level)
+	if name, ok := h.levelNames[r.Level]; ok {
+		buffer.WriteString(name)
+	} else {
+		switch r.Level {
+		case slog.LevelDebug:
+			buffer.WriteString("DBG")
+		case slog.LevelInfo:
+			buffer.WriteString("INF")
+		case slog.LevelWarn:
+			buffer.WriteString("WRN")
+		case slog.LevelError:
+			buffer.WriteString("ERR")
+		default:
+			fmt.Fprintf(&buffer, "%3d", r.Level)
+		}
 	}
 	buffer.WriteString(r.Time.Round(0).Format(" | 2006-01-02 | 15:04:05.000 | "))
 	buffer.WriteString(r.Message)