feat: support human readable timestamps (#38)

Co-authored-by: Maksym Kryvchun <hedhyw@yahoo.com>

README.md

@@ -107,10 +107,14 @@ Example configuration:
             "title": "Time", // Max length is 32.
             // Kind affects rendering. There are:
             // * time;
+            // * numerictime;
+            // * secondtime;
+            // * millitime;
+            // * microtime;
             // * level;
             // * message;
             // * any.
-            "kind": "time",
+            "kind": "numerictime",
             "ref": [
                 // The application will display the first matched value.
                 "$.timestamp",
@@ -153,6 +157,28 @@ Example configuration:
 }
 ```
 
+### Time Formats
+JSON Log Viewer can handle a variety of datetime formats when parsing your logs.
+
+#### `time`
+This will return the exact value that was set in the JSON document.
+
+#### `numerictime`
+This is a "smart" parser. It can accept an integer, a float, or a string. If it is numeric (`1234443`, `1234443.589`, `"1234443"`, `"1234443.589"`), based on the number of digits, it will parse as seconds, milliseconds, or microseconds. The output is a UTC-based RFC 3339 datetime.
+
+If a string such as `"2023-05-01T12:00:34Z"` or `"---"` is used, the value will just be carried forward to your column.  
+
+If you find that the smart parsing is giving unwanted results or you need greater control over how a datetime is parsed, considered using one of the other time formats instead.
+
+#### `secondtime`
+This will attempt to parse the value as number of seconds and render as a UTC-based RFC 3339. Values accepted are integer, string, or float.
+
+#### `millitime`
+Similar to `secondtime`, this will attempt to parse the value as number of milliseconds. Values accepted are integer, string, or float.
+
+#### `microtime`
+Similar to `secondtime` and `millistime`, this will attempt to parse the value as number of microseconds. Values accepted are integer, string, or float.
+
 ## Resources
 
 Alternatives:

assets/example.log

@@ -45,3 +45,11 @@
 {"time":"1970-01-01T00:00:00.00","level":"DEBUG","message": "A house divided against itself cannot stand.","author": "Abraham Lincoln"}
 {"time":"1970-01-01T00:00:00.00","level":"TRACE","message": "Difficulties increase the nearer we get to the goal.","author": "Johann Wolfgang von Goethe"}
 plain text log
+{"time":"12444334.222","level":"TRACE","message": "Wealth consists not in having great possessions, but in having few wants.","author": "Epictetus"}
+{"time":12444334.222,"level":"INFO","message": "Laugh at the world's foolishness or weep over it, you will regret both","author": "Kierkegaard"}
+{"time":12444334,"level":"WARN","message": "Wealth consists not in having great possessions, but in having few wants.","author": "Epictetus"}
+{"time":"12444334","level":"DEBUG","message": "Wealth consists not in having great possessions, but in having few wants.","author": "Epictetus"}
+{"time":124999444443,"level":"TRACE","message": "Money doesn't talk, it swears","author": "Bob Dylan"}
+{"time":124999444443.45,"level":"WARN","message": "If a man knows not to which port he sails, no wind is favorable","author": "Seneca"}
+{"time":"124999444443.45","level":"VERBOSE","message": "Begin at once to live, and count each separate day as a separate life","author": "Seneca"}
+{"time":12499944444398.45,"level":"VERBOSE","message": "Begin at once to live, and count each separate day as a separate life","author": "Seneca"}

internal/pkg/config/config.go

@@ -26,16 +26,20 @@ type FieldKind string
 
 // Possible kinds.
 const (
-	FieldKindTime    FieldKind = "time"
-	FieldKindMessage FieldKind = "message"
-	FieldKindLevel   FieldKind = "level"
-	FieldKindAny     FieldKind = "any"
+	FieldKindTime        FieldKind = "time"
+	FieldKindNumericTime FieldKind = "numerictime"
+	FieldKindSecondTime  FieldKind = "secondtime"
+	FieldKindMilliTime   FieldKind = "millitime"
+	FieldKindMicroTime   FieldKind = "microtime"
+	FieldKindMessage     FieldKind = "message"
+	FieldKindLevel       FieldKind = "level"
+	FieldKindAny         FieldKind = "any"
 )
 
 // Field customization.
 type Field struct {
 	Title      string    `json:"title" validate:"required,min=1,max=32"`
-	Kind       FieldKind `json:"kind" validate:"required,oneof=time message level any"`
+	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"`
 }
@@ -46,7 +50,7 @@ func GetDefaultConfig() *Config {
 		Path: "default",
 		Fields: []Field{{
 			Title:      "Time",
-			Kind:       FieldKindTime,
+			Kind:       FieldKindNumericTime,
 			References: []string{"$.timestamp", "$.time", "$.t", "$.ts"},
 			Width:      30,
 		}, {

internal/pkg/config/config_test.go

@@ -103,7 +103,7 @@ func ExampleGetDefaultConfig() {
 	// 	"fields": [
 	// 		{
 	// 			"title": "Time",
-	// 			"kind": "time",
+	// 			"kind": "numerictime",
 	// 			"ref": [
 	// 				"$.timestamp",
 	// 				"$.time",
@@ -208,6 +208,30 @@ func TestValidateField(t *testing.T) {
 			value.Kind = config.FieldKindTime
 		},
 		IsValid: true,
+	}, {
+		Name: "kind_numeric_time",
+		Apply: func(value *config.Field) {
+			value.Kind = config.FieldKindNumericTime
+		},
+		IsValid: true,
+	}, {
+		Name: "kind_second_time",
+		Apply: func(value *config.Field) {
+			value.Kind = config.FieldKindSecondTime
+		},
+		IsValid: true,
+	}, {
+		Name: "kind_milli_time",
+		Apply: func(value *config.Field) {
+			value.Kind = config.FieldKindMilliTime
+		},
+		IsValid: true,
+	}, {
+		Name: "kind_micro_time",
+		Apply: func(value *config.Field) {
+			value.Kind = config.FieldKindMicroTime
+		},
+		IsValid: true,
 	}, {
 		Name: "unset_kind",
 		Apply: func(value *config.Field) {

internal/pkg/source/entry.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"strconv"
 	"strings"
+	"time"
 	"unicode"
 
 	"github.com/charmbracelet/bubbles/table"
@@ -79,8 +80,11 @@ func parseField(parsedLine any, field config.Field) string {
 		}
 
 		unquotedField, err := strconv.Unquote(string(jsonField))
+		// It's possible that what we were given is an integer or float
+		// in which case, calling Unquote isn't doing us a lot of good.
+		// Therefore, we just convert to a string value and proceed.
 		if err != nil {
-			return string(jsonField)
+			unquotedField = string(jsonField)
 		}
 
 		return formatField(unquotedField, field.Kind)
@@ -89,19 +93,33 @@ func parseField(parsedLine any, field config.Field) string {
 	return "-"
 }
 
+//nolint:cyclop // The cyclomatic complexity here is so high because of the number of FieldKinds.
 func formatField(
 	value string,
 	kind config.FieldKind,
 ) string {
 	value = strings.TrimSpace(value)
 
+	// Numeric time attempts to infer the duration based on the length of the string
+	if kind == config.FieldKindNumericTime {
+		kind = guessTimeFieldKind(value)
+	}
+
 	switch kind {
 	case config.FieldKindMessage:
 		return formatMessage(value)
 	case config.FieldKindLevel:
 		return string(ParseLevel(formatMessage(value)))
 	case config.FieldKindTime:
 		return formatMessage(value)
+	case config.FieldKindNumericTime:
+		return formatMessage(value)
+	case config.FieldKindSecondTime:
+		return formatMessage(formatTimeString(value, "s"))
+	case config.FieldKindMilliTime:
+		return formatMessage(formatTimeString(value, "ms"))
+	case config.FieldKindMicroTime:
+		return formatMessage(formatTimeString(value, "us"))
 	case config.FieldKindAny:
 		return formatMessage(value)
 	default:
@@ -166,3 +184,38 @@ func formatMessage(msg string) string {
 
 	return msg
 }
+
+// We can only guess the time via a heuristic. We do this by looking at the number of digits
+// (before the decimal point) in the string. This is far from perfect.
+func guessTimeFieldKind(timeStr string) config.FieldKind {
+	intValue, err := strconv.ParseInt(strings.Split(timeStr, ".")[0], 10, 64)
+	if err != nil {
+		return config.FieldKindTime
+	}
+
+	if intValue <= 0 {
+		return config.FieldKindTime
+	}
+
+	intLength := len(strconv.FormatInt(intValue, 10))
+
+	switch {
+	case intLength <= 10:
+		return config.FieldKindSecondTime
+	case intLength > 10 && intLength <= 13:
+		return config.FieldKindMilliTime
+	case intLength > 13 && intLength <= 16:
+		return config.FieldKindMicroTime
+	default:
+		return config.FieldKindTime
+	}
+}
+
+func formatTimeString(timeStr string, unit string) string {
+	duration, err := time.ParseDuration(timeStr + unit)
+	if err != nil {
+		return timeStr
+	}
+
+	return time.UnixMilli(0).Add(duration).UTC().Format(time.RFC3339)
+}