From c03ba46862ad78c00d9d7ddf7f1a70138fad82cd Mon Sep 17 00:00:00 2001
From: denisevdkmv <denisevdkmv@yandex-team.com>
Date: Thu, 27 Feb 2025 12:32:51 +0300
Subject: [PATCH] Add datetime parser validation and test for GenericParser
 commit_hash:5f78134ef29c7448b99fe272d7cc46e5e6c4ffcf

---
 pkg/parsers/generic/generic_parser.go    | 22 +++++++++++++--
 pkg/parsers/tests/generic_parser_test.go | 36 ++++++++++++++++++++++++
 2 files changed, 56 insertions(+), 2 deletions(-)

diff --git a/pkg/parsers/generic/generic_parser.go b/pkg/parsers/generic/generic_parser.go
index 45dca8d4..6dd5ec92 100644
--- a/pkg/parsers/generic/generic_parser.go
+++ b/pkg/parsers/generic/generic_parser.go
@@ -214,7 +214,6 @@ type lfResult struct {
 
 type lfResultBatch []lfResult
 
-var loc = time.Now().Location()
 var (
 	UnparsedCols = cols(UnparsedSchema.Columns())
 )
@@ -839,7 +838,7 @@ func (p *GenericParser) extractTimeValue(col interface{}, defaultTime time.Time)
 			}
 		}
 
-		if t, err := dateparse.ParseIn(v, loc); err == nil {
+		if t, err := dateparse.ParseLocal(v); err == nil {
 			return &t, true, nil
 		} else {
 			if t, err := time.Parse("2006.01.02 15:04:05.999999", v); err == nil {
@@ -1140,6 +1139,24 @@ func (p *GenericParser) ResultSchema() *abstract.TableSchema {
 	return p.schema
 }
 
+func checkParserCorrectness(opts AuxParserOpts, sch []abstract.ColSchema, lgr log.Logger) {
+	if opts.InferTimeZone || (opts.TimeField != nil && opts.TimeField.Format != "") {
+		return
+	}
+
+	hasDatetime := false
+	for _, col := range sch {
+		if col.DataType == schema.TypeDatetime.String() {
+			hasDatetime = true
+			break
+		}
+	}
+
+	if hasDatetime {
+		lgr.Warn("the datetime fields will be parsed in local timezone, because infer timezone and time field are not configured")
+	}
+}
+
 func NewGenericParser(cfg ParserConfig, fields []abstract.ColSchema, logger log.Logger, registry *stats.SourceStats) *GenericParser {
 	var opts *AuxParserOpts
 	var lfCfg *LogfellerParserConfig
@@ -1184,6 +1201,7 @@ func NewGenericParser(cfg ParserConfig, fields []abstract.ColSchema, logger log.
 		}
 	}
 	logger.Info("Final schema", log.Any("columns", colNames), log.Any("s", finalSchema))
+	checkParserCorrectness(*opts, finalSchema, logger)
 	return &GenericParser{
 		rawFields:        fields,
 		known:            known,
diff --git a/pkg/parsers/tests/generic_parser_test.go b/pkg/parsers/tests/generic_parser_test.go
index d7ccb9c2..68a8d100 100644
--- a/pkg/parsers/tests/generic_parser_test.go
+++ b/pkg/parsers/tests/generic_parser_test.go
@@ -16,6 +16,7 @@ import (
 	"github.com/doublecloud/transfer/pkg/parsers"
 	"github.com/doublecloud/transfer/pkg/parsers/generic"
 	_ "github.com/doublecloud/transfer/pkg/parsers/registry"
+	jsonparser "github.com/doublecloud/transfer/pkg/parsers/registry/json"
 	"github.com/doublecloud/transfer/pkg/parsers/registry/tskv"
 	"github.com/doublecloud/transfer/pkg/parsers/tests/samples"
 	"github.com/doublecloud/transfer/pkg/providers/kafka"
@@ -391,6 +392,41 @@ func TestGenericParser_Parse_vs_Do(t *testing.T) {
 	}
 }
 
+func TestGenericParserDatetimeZone(t *testing.T) {
+	parserConfigStruct := &jsonparser.ParserConfigJSONLb{
+		Fields: []abstract.ColSchema{
+			{ColumnName: "timestamp", DataType: schema.TypeDatetime.String()},
+		},
+		TimeField: &abstract.TimestampCol{
+			Col:    "timestamp",
+			Format: "2006-01-02T15:04:05.000Z",
+		},
+	}
+	configMap, err := parsers.ParserConfigStructToMap(parserConfigStruct)
+	require.NoError(t, err)
+	parser, err := parsers.NewParserFromMap(configMap, false, logger.Log, stats.NewSourceStats(metrics.NewRegistry()))
+	require.NoError(t, err)
+
+	res := parser.Do(parsers.Message{
+		Value: []byte("{\"timestamp\":\"2025-02-19T15:43:30.089Z\"}"),
+	}, abstract.Partition{Partition: 0, Topic: "test/topic"})
+
+	require.NotEmpty(t, res)
+	require.NotEmpty(t, res[0].ColumnValues)
+
+	tsIdx := -1
+	for idx, col := range res[0].ColumnNames {
+		if col == "timestamp" {
+			tsIdx = idx
+		}
+	}
+	require.True(t, tsIdx >= 0)
+
+	ts, ok := res[0].ColumnValues[tsIdx].(time.Time)
+	require.True(t, ok)
+	require.Equal(t, time.UTC.String(), ts.Location().String())
+}
+
 func BenchmarkGenericParser(b *testing.B) {
 	for _, testCase := range []string{
 		samples.MetrikaSample, // tskv