enable log colorization in development

I'm waiting on upstream to merge two merge requests.

Merge-Request: https://gitlab.com/greyxor/slogor/-/merge_requests/7
Merge-Request: https://gitlab.com/greyxor/slogor/-/merge_requests/8

Author: dmke

cmd/texd/main.go

@@ -286,7 +286,7 @@ func setupLogger() (xlog.Logger, error) {
 		xlog.WithSource(),
 	}
 	if texd.Development() {
-		o = append(o, xlog.WriteTo(os.Stderr), xlog.AsText())
+		o = append(o, xlog.WriteTo(os.Stderr), xlog.AsText(), xlog.Color())
 	} else {
 		o = append(o, xlog.WriteTo(os.Stdout), xlog.AsJSON())
 	}

go.mod

@@ -9,6 +9,7 @@ require (
 	github.com/docker/go-units v0.5.0
 	github.com/gorilla/handlers v1.5.2
 	github.com/gorilla/mux v1.8.1
+	github.com/mattn/go-isatty v0.0.20
 	github.com/moby/term v0.5.0
 	github.com/oklog/ulid/v2 v2.1.0
 	github.com/opencontainers/image-spec v1.1.0
@@ -17,6 +18,7 @@ require (
 	github.com/spf13/pflag v1.0.5
 	github.com/stretchr/testify v1.9.0
 	github.com/thediveo/enumflag v0.10.1
+	gitlab.com/greyxor/slogor v1.4.1
 )
 
 require (
@@ -61,3 +63,5 @@ require (
 )
 
 replace github.com/spf13/afero => github.com/digineo/afero v1.11.1-0.20240128222722-ade8094005cb
+
+replace gitlab.com/greyxor/slogor => gitlab.com/dmke/slogor v1.4.2-0.20241030183918-8885575df1e5

go.sum

@@ -1456,6 +1456,8 @@ github.com/magiconair/properties v1.8.0/go.mod h1:PppfXfuXeibc/6YijjN8zIbojt8czP
 github.com/mattn/go-isatty v0.0.12/go.mod h1:cbi8OIDigv2wuxKPP5vlRcQ1OAZbq2CE4Kysco4FUpU=
 github.com/mattn/go-isatty v0.0.16/go.mod h1:kYGgaQfpe5nmfYZH+SKPsOc2e4SrIfOl2e/yFXSvRLM=
 github.com/mattn/go-isatty v0.0.17/go.mod h1:kYGgaQfpe5nmfYZH+SKPsOc2e4SrIfOl2e/yFXSvRLM=
+github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
+github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
 github.com/mattn/go-sqlite3 v1.14.14/go.mod h1:NyWgC/yNuGj7Q9rpYnZvas74GogHl5/Z4A/KQRfk6bU=
 github.com/mattn/go-sqlite3 v1.14.15/go.mod h1:2eHXhiwb8IkHr+BDWZGa96P6+rkvnG63S2DGjv9HUNg=
 github.com/matttproud/golang_protobuf_extensions v1.0.1/go.mod h1:D8He9yQNgCq6Z5Ld7szi9bcBfOoFv/3dc6xSMkL2PC0=
@@ -1588,6 +1590,8 @@ github.com/yuin/goldmark v1.4.1/go.mod h1:mwnBkeHKe2W/ZEtQ+71ViKU8L12m81fl3OWwC1
 github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
 github.com/zeebo/assert v1.3.0/go.mod h1:Pq9JiuJQpG8JLJdtkwrJESF0Foym2/D9XMU5ciN/wJ0=
 github.com/zeebo/xxh3 v1.0.2/go.mod h1:5NWz9Sef7zIDm2JHfFlcQvNekmcEl9ekUZQQKCYaDcA=
+gitlab.com/dmke/slogor v1.4.2-0.20241030183918-8885575df1e5 h1:oIZBFZcMCiRwi1CdWSf62YF4XKq0GyhKIBsxZo24AWw=
+gitlab.com/dmke/slogor v1.4.2-0.20241030183918-8885575df1e5/go.mod h1:RvD/RqmEGpqVhL8tqqfVduuxtcik6uXCnzfikaFCwto=
 go.etcd.io/bbolt v1.3.2/go.mod h1:IbVyRI1SCnLcuJnV2u8VeU0CEYM7e686BmAb1XKL+uU=
 go.opencensus.io v0.21.0/go.mod h1:mSImk1erAIZhrmZN+AvHh14ztQfjbGwt4TtuofqLduU=
 go.opencensus.io v0.22.0/go.mod h1:+kGneAE2xo2IficOXnaByMWTGM9T73dGwxeWcUqIpI8=

service/middleware/logging_test.go

@@ -36,9 +36,8 @@ func TestLogging(t *testing.T) {
 	require.Equal(t, http.StatusOK, w.Code)
 
 	assert.Equal(t, strings.Join([]string{
-		"time=2022-04-15T05:20:00.000Z",
-		"level=INFO",
-		`msg=""`,
+		"[05:20:00.000] INFO logging.go:68",
+		"",
 		"method=GET",
 		"status=200",
 		"bytes=0",

service/status_test.go

@@ -85,9 +85,8 @@ func TestHandleStatus_withFailIO(t *testing.T) {
 	assert.Equal(t, http.StatusOK, rec.code)
 	assert.Equal(t, mimeTypeJSON, rec.h.Get("Content-Type"))
 	assert.Equal(t, strings.Join([]string{
-		"time=2022-04-15T05:20:00.000Z",
-		"level=ERROR",
-		`msg="failed to write response"`,
+		"[05:20:00.000] ERROR status.go:46",
+		"failed to write response",
 		`error="io: read/write on closed pipe"`,
 	}, " ")+"\n", buf.String())
 }

xlog/attrs.go

@@ -23,11 +23,18 @@ const ErrorKey = "error"
 // ErrorValue holds an error value.
 type ErrorValue struct{ error }
 
+var _ slog.LogValuer = (*ErrorValue)(nil)
+
 // Value extracts the error message.
 func (err ErrorValue) Value() slog.Value {
 	return slog.StringValue(err.Error())
 }
 
+// LogValue implements [slog.LogValuer].
+func (err ErrorValue) LogValue() slog.Value {
+	return slog.StringValue(err.Error())
+}
+
 // Error constructs a first-class error log attribute.
 //
 // Not to be confused with (xlog.Logger).Error() or (log/slog).Error(),

xlog/options.go

@@ -3,27 +3,33 @@ package xlog
 import (
 	"io"
 	"log/slog"
+	"os"
 	"time"
 
 	"github.com/digineo/texd/internal"
+	"github.com/mattn/go-isatty"
+	"gitlab.com/greyxor/slogor"
 )
 
 // An Option represents a functional configuration option. These are
 // used to configure new logger instances.
 type Option func(*options) error
 
 type options struct {
-	discard      bool
-	output       io.Writer
-	clock        internal.Clock
+	discard bool
+	output  io.Writer
+	color   bool
+	clock   internal.Clock
+	level   slog.Leveler
+	source  bool
+
 	buildHandler func(o *options) slog.Handler
-	handlerOpts  *slog.HandlerOptions
 }
 
 // Leveled sets the log level.
 func Leveled(l slog.Level) Option {
 	return func(o *options) error {
-		o.handlerOpts.Level = l
+		o.level = l
 		return nil
 	}
 }
@@ -36,7 +42,7 @@ func LeveledString(s string) Option {
 		if err != nil {
 			return err
 		}
-		o.handlerOpts.Level = l
+		o.level = l
 		return nil
 	}
 }
@@ -60,16 +66,17 @@ func MockClock(t time.Time) Option {
 // WithSource enables source code positions in log messages.
 func WithSource() Option {
 	return func(o *options) error {
-		o.handlerOpts.AddSource = true
+		o.source = true
 		return nil
 	}
 }
 
-// WithAttrReplacer configures an attribute replacer.
-// See (slog.HandlerOptions).ReplaceAtrr for details.
-func WithAttrReplacer(f func(groups []string, a slog.Attr) slog.Attr) Option {
+// Color enables colorful log output. If the output writer set by
+// [WriteTo] isn't a TTY, or messages are output [AsJSON], enabling
+// colors won't have an effect.
+func Color() Option {
 	return func(o *options) error {
-		o.handlerOpts.ReplaceAttr = f
+		o.color = true
 		return nil
 	}
 }
@@ -79,7 +86,10 @@ func WithAttrReplacer(f func(groups []string, a slog.Attr) slog.Attr) Option {
 func AsJSON() Option {
 	return func(o *options) error {
 		o.buildHandler = func(o *options) slog.Handler {
-			return slog.NewJSONHandler(o.output, o.handlerOpts)
+			return slog.NewJSONHandler(o.output, &slog.HandlerOptions{
+				AddSource: o.source,
+				Level:     o.level,
+			})
 		}
 		return nil
 	}
@@ -90,7 +100,15 @@ func AsJSON() Option {
 func AsText() Option {
 	return func(o *options) error {
 		o.buildHandler = func(o *options) slog.Handler {
-			return slog.NewTextHandler(o.output, o.handlerOpts)
+			opts := []slogor.OptionFn{
+				slogor.SetLevel(o.level.Level()),
+				slogor.SetTimeFormat("[15:04:05.000]"),
+				slogor.ShowSource(),
+			}
+			if f, isFile := o.output.(*os.File); !isFile || !isatty.IsTerminal(f.Fd()) {
+				opts = append(opts, slogor.DisableColor())
+			}
+			return slogor.NewHandler(o.output, opts...)
 		}
 		return nil
 	}

xlog/xlog.go

@@ -1,4 +1,4 @@
-// Package xlog provides a very thin wrapper aroud log/slog.
+// Package xlog provides a thin wrapper around [log/slog].
 package xlog
 
 import (
@@ -9,6 +9,8 @@ import (
 	"runtime"
 	"strings"
 	"time"
+
+	"github.com/digineo/texd/internal"
 )
 
 // A Logger allows writing messages with various severities.
@@ -37,8 +39,8 @@ type logger struct {
 // written to stdout, and the log level is INFO.
 func New(opt ...Option) (Logger, error) {
 	opts := options{
-		output:      os.Stdout,
-		handlerOpts: &slog.HandlerOptions{},
+		level:  slog.LevelInfo,
+		output: os.Stdout,
 	}
 
 	for _, o := range opt {
@@ -53,22 +55,15 @@ func New(opt ...Option) (Logger, error) {
 	}
 
 	// setup mock time
+	h := opts.buildHandler(&opts)
 	if opts.clock != nil {
-		repl := opts.handlerOpts.ReplaceAttr
-		opts.handlerOpts.ReplaceAttr = func(groups []string, a slog.Attr) slog.Attr {
-			if len(groups) == 0 && a.Key == slog.TimeKey {
-				a.Value = slog.TimeValue(opts.clock.Now())
-			}
-			if repl == nil {
-				return a
-			}
-			return repl(groups, a)
+		h = &mockTimeHandler{
+			clock:   opts.clock,
+			Handler: h,
 		}
 	}
 
-	return &logger{
-		l: slog.New(opts.buildHandler(&opts)),
-	}, nil
+	return &logger{l: slog.New(h)}, nil
 }
 
 // log creates a log record. It is called by Debug, Info, etc.
@@ -77,7 +72,7 @@ func (log *logger) log(level slog.Level, msg string, a ...slog.Attr) {
 		return
 	}
 	var pcs [1]uintptr
-	runtime.Callers(3, pcs[:]) // skip runtime.Callers, log, and our caller
+	runtime.Callers(3, pcs[:]) //nolint:mnd // skip runtime.Callers, log, and our caller
 	r := slog.NewRecord(time.Now(), level, msg, pcs[0])
 	r.AddAttrs(a...)
 	_ = log.l.Handler().Handle(context.Background(), r)
@@ -129,3 +124,13 @@ func ParseLevel(s string) (l slog.Level, err error) {
 	}
 	return
 }
+
+type mockTimeHandler struct {
+	clock internal.Clock
+	slog.Handler
+}
+
+func (h *mockTimeHandler) Handle(ctx context.Context, a slog.Record) error {
+	a.Time = h.clock.Now()
+	return h.Handler.Handle(ctx, a)
+}