Autodetect datetime format

main.go

@@ -4,7 +4,6 @@ import (
 	"log"
 	"os"
 	"path/filepath"
-	"time"
 )
 
 func init() {
@@ -56,25 +55,9 @@ func main() {
 			log.Fatalln(err)
 		}
 
-		var t time.Time
-		switch len(os.Args[4]) {
-		case len("02.01.2006"):
-			t, err = time.Parse("02.01.2006 15:04", os.Args[4])
-			if err != nil {
-				config.fatalln("time parse error:", err)
-			}
-		case len("02.01.2006 15:04"):
-			t, err = time.Parse("02.01.2006 15:04", os.Args[4])
-			if err != nil {
-				config.fatalln("time parse error:", err)
-			}
-		case len("02.01.2006 15:04:05"):
-			t, err = time.Parse("02.01.2006 15:04:05", os.Args[4])
-			if err != nil {
-				config.fatalln("time parse error:", err)
-			}
-		default:
-			config.fatalln(`wrong time format, must be ["DD.MM.YYYY", "DD.MM.YYYY hh:mm", "DD.MM.YYYY hh:mm:ss"]`)
+		t, err := parseTime(os.Args[4])
+		if err != nil {
+			config.fatalln(err)
 		}
 
 		plan, err := config.extractionPlan(os.Args[3], t)

utils.go

@@ -1,9 +1,11 @@
 package main
 
 import (
+	"errors"
 	"fmt"
 	"path/filepath"
 	"strings"
+	"time"
 
 	"github.com/tidwall/match"
 )
@@ -71,3 +73,16 @@ func isFilePathMatchPatterns(patterns []string, fileName string) bool {
 
 	return false
 }
+
+func parseTime(s string) (time.Time, error) {
+	switch len(s) {
+	case len("02.01.2006"):
+		return time.ParseInLocation("02.01.2006", s, time.Local)
+	case len("02.01.2006 15:04"):
+		return time.ParseInLocation("02.01.2006 15:04", s, time.Local)
+	case len("02.01.2006 15:04:05"):
+		return time.ParseInLocation("02.01.2006 15:04:05", s, time.Local)
+	}
+
+	return time.Time{}, errors.New("unknown time format")
+}

utils_test.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"testing"
+	"time"
 
 	"github.com/stretchr/testify/assert"
 )
@@ -10,3 +11,21 @@ func TestSizeToApproxHuman(t *testing.T) {
 	assert.Equal(t, "1.0 KiB", sizeToApproxHuman(1024))
 	assert.Equal(t, "1.1 KiB", sizeToApproxHuman(1126))
 }
+
+func TestParseTime(t *testing.T) {
+	tests := []struct {
+		input    string
+		expected time.Time
+	}{
+		{"02.01.2006", time.Date(2006, 01, 02, 0, 0, 0, 0, time.Local)},
+		{"02.01.2006 15:04", time.Date(2006, 01, 02, 15, 4, 0, 0, time.Local)},
+		{"02.01.2006 15:04:05", time.Date(2006, 01, 02, 15, 4, 5, 0, time.Local)},
+	}
+
+	for _, test := range tests {
+		got, err := parseTime(test.input)
+		assert.NoError(t, err)
+
+		assert.Equal(t, test.expected, got)
+	}
+}