feat: support default reverse mode in the config

example.jlv.jsonc

@@ -33,7 +33,7 @@
             //	AM/PM mark: "PM"
             //
             // More details: https://go.dev/src/time/format.go.
-            "time_format": "2006-01-02T15:04:05Z07:00"
+            "timeFormat": "2006-01-02T15:04:05Z07:00"
         },
         {
             "title": "Level",
@@ -65,13 +65,15 @@
             "width": 0
         }
     ],
+    // Show logs in reverse order by default.
+    "isReverseDefault": true,
     // Time layouts to reformat.
     //
     // If the time field has been parsed to any of the specified layouts,
-    // it will be formatted according to "time_format" configuration.
+    // it will be formatted according to "timeFormat" configuration.
     //
     // See: https://pkg.go.dev/time#pkg-constants.
-    "time_layouts": [
+    "timeLayouts": [
 	    "01/02 03:04:05PM '06 -0700",
 	    "Mon Jan _2 15:04:05 2006",
 	    "Mon Jan _2 15:04:05 MST 2006",

internal/app/app_test.go

@@ -19,14 +19,26 @@ import (
 
 const testVersion = "v0.0.1"
 
-func newTestModel(tb testing.TB, content []byte) tea.Model {
+type configSetter func(*config.Config)
+
+func newTestModel(
+	tb testing.TB,
+	content []byte,
+	configSetters ...configSetter,
+) tea.Model {
 	tb.Helper()
 
 	testFile := tests.RequireCreateFile(tb, content)
 
-	inputSource, err := source.File(testFile, config.GetDefaultConfig())
+	cfg := config.GetDefaultConfig()
+
+	for _, set := range configSetters {
+		set(cfg)
+	}
+
+	inputSource, err := source.File(testFile, cfg)
 	require.NoError(tb, err)
-	model := app.NewModel(testFile, config.GetDefaultConfig(), testVersion)
+	model := app.NewModel(testFile, cfg, testVersion)
 
 	entries, err := inputSource.ParseLogEntries()
 	require.NoError(tb, err)

internal/app/stateloaded.go

@@ -26,8 +26,8 @@ func newStateViewLogs(
 	table := newLogsTableModel(
 		application,
 		logEntries,
-		true, // follow.
-		true, // reverse.
+		true,                                // follow.
+		application.Config.IsReverseDefault, // reverse.
 	)
 
 	return StateLoadedModel{

internal/app/stateloaded_test.go

@@ -32,10 +32,10 @@ func TestStateLoadedEmpty(t *testing.T) {
 func TestStateLoaded(t *testing.T) {
 	t.Parallel()
 
-	setup := func() tea.Model {
+	setup := func(configSetters ...configSetter) tea.Model {
 		const jsonFile = `{"time":"1970-01-01T00:00:00.00","level":"INFO","message": "test"}`
 
-		model := newTestModel(t, []byte(jsonFile))
+		model := newTestModel(t, []byte(jsonFile), configSetters...)
 
 		_, ok := model.(app.StateLoadedModel)
 		require.Truef(t, ok, "%s", model)
@@ -111,6 +111,17 @@ func TestStateLoaded(t *testing.T) {
 		assert.Contains(t, view, "reverse")
 	})
 
+	t.Run("label_reverse_disabled_in_config", func(t *testing.T) {
+		t.Parallel()
+
+		model := setup(func(cfg *config.Config) {
+			cfg.IsReverseDefault = false
+		})
+
+		view := model.View()
+		assert.NotContains(t, view, "reverse")
+	})
+
 	t.Run("label_not_reverse", func(t *testing.T) {
 		t.Parallel()
 

internal/pkg/config/config.go

@@ -25,8 +25,12 @@ type Config struct {
 	Path string `json:"-"`
 
 	Fields []Field `json:"fields" validate:"min=1"`
+
+	TimeLayoutsDeprecated []string `json:"time_layouts,omitempty"`
 	// TimeLayouts to reformat.
-	TimeLayouts []string `json:"time_layouts"`
+	TimeLayouts []string `json:"timeLayouts"`
+
+	IsReverseDefault bool `json:"isReverseDefault"`
 
 	CustomLevelMapping map[string]string `json:"customLevelMapping"`
 
@@ -55,7 +59,9 @@ type Field struct {
 	Kind       FieldKind `json:"kind" validate:"required,oneof=time message numerictime secondtime millitime microtime level any"`
 	References []string  `json:"ref" validate:"min=1,dive,required"`
 	Width      int       `json:"width" validate:"min=0"`
-	TimeFormat *string   `json:"time_format,omitempty"`
+
+	TimeFormatDeprecated *string `json:"time_format,omitempty"`
+	TimeFormat           *string `json:"timeFormat,omitempty"`
 }
 
 // GetDefaultConfig returns the configuration with default values.
@@ -102,6 +108,7 @@ func GetDefaultConfig() *Config {
 			Kind:       FieldKindMessage,
 			References: []string{"$.message", "$.msg", "$.error", "$.err"},
 		}},
+		IsReverseDefault: true,
 	}
 }
 
@@ -165,6 +172,18 @@ func readConfigFromFile(path string) (cfg *Config, err error) {
 
 	cfg.Path = path
 
+	if len(cfg.TimeLayoutsDeprecated) != 0 {
+		cfg.TimeLayouts = cfg.TimeLayoutsDeprecated
+	}
+
+	for i, f := range cfg.Fields {
+		if f.TimeFormatDeprecated != nil && *f.TimeFormatDeprecated != "" {
+			f.TimeFormat = f.TimeFormatDeprecated
+		}
+
+		cfg.Fields[i] = f
+	}
+
 	return cfg, nil
 }
 

internal/pkg/config/config_test.go

@@ -114,7 +114,7 @@ func ExampleGetDefaultConfig() {
 	//         "$[\"@timestamp\"]"
 	//       ],
 	//       "width": 30,
-	//       "time_format": "2006-01-02T15:04:05Z07:00"
+	//       "timeFormat": "2006-01-02T15:04:05Z07:00"
 	//     },
 	//     {
 	//       "title": "Level",
@@ -138,7 +138,7 @@ func ExampleGetDefaultConfig() {
 	//       "width": 0
 	//     }
 	//   ],
-	//   "time_layouts": [
+	//   "timeLayouts": [
 	//     "01/02 03:04:05PM '06 -0700",
 	//     "Mon Jan _2 15:04:05 2006",
 	//     "Mon Jan _2 15:04:05 MST 2006",
@@ -157,6 +157,7 @@ func ExampleGetDefaultConfig() {
 	//     "2006-01-02 15:04:05",
 	//     "2006-01-02"
 	//   ],
+	//   "isReverseDefault": true,
 	//   "customLevelMapping": {
 	//     "10": "trace",
 	//     "20": "debug",
@@ -395,3 +396,42 @@ func TestByteSizeParseFailed(t *testing.T) {
 		require.Error(t, err)
 	})
 }
+
+func TestReadTimeLayoutsDeprecated(t *testing.T) {
+	t.Parallel()
+
+	cfg := config.GetDefaultConfig()
+	cfg.TimeLayoutsDeprecated = []string{time.Layout}
+	cfg.TimeLayouts = nil
+
+	configJSON := tests.RequireEncodeJSON(t, cfg)
+	fileFirst := tests.RequireCreateFile(t, configJSON)
+
+	actual, err := config.Read(fileFirst)
+	if assert.NoError(t, err) {
+		assert.ElementsMatch(t, actual.TimeLayouts, cfg.TimeLayoutsDeprecated)
+	}
+}
+
+func TestReadTimeFormatDeprecated(t *testing.T) {
+	t.Parallel()
+
+	timeFormat := time.Layout
+
+	cfg := config.GetDefaultConfig()
+	cfg.Fields = []config.Field{{
+		Title:                "Time",
+		Kind:                 config.FieldKindNumericTime,
+		References:           []string{"$.timestamp", "$.time", "$.t", "$.ts", "$[\"@timestamp\"]"},
+		Width:                30,
+		TimeFormatDeprecated: &timeFormat,
+	}}
+
+	configJSON := tests.RequireEncodeJSON(t, cfg)
+	fileFirst := tests.RequireCreateFile(t, configJSON)
+
+	actual, err := config.Read(fileFirst)
+	if assert.NoError(t, err) {
+		assert.Equal(t, timeFormat, *actual.Fields[0].TimeFormat)
+	}
+}