From 8d6f16ef479e6b661214c4d93cf30cdb6cbee138 Mon Sep 17 00:00:00 2001
From: Robin Tang <rtang.cs@gmail.com>
Date: Sun, 15 Dec 2024 22:23:57 -0800
Subject: [PATCH] String converters.

---
 lib/typing/converters/converters.go | 33 +++++++++++++++++++++++++++++
 lib/typing/values/string.go         | 19 +++++++++++------
 2 files changed, 45 insertions(+), 7 deletions(-)
 create mode 100644 lib/typing/converters/converters.go

diff --git a/lib/typing/converters/converters.go b/lib/typing/converters/converters.go
new file mode 100644
index 000000000..a01558b73
--- /dev/null
+++ b/lib/typing/converters/converters.go
@@ -0,0 +1,33 @@
+package converters
+
+import (
+	"fmt"
+
+	"github.com/artie-labs/transfer/lib/typing"
+
+	"github.com/artie-labs/transfer/lib/typing/ext"
+)
+
+type StringConverter interface {
+	Convert(value any) (string, error)
+}
+
+func GetStringConverter(kd typing.KindDetails) (StringConverter, error) {
+	switch kd.Kind {
+	case typing.Date.Kind:
+		return DateStringConverter{}, nil
+	}
+
+	return nil, nil
+}
+
+type DateStringConverter struct{}
+
+func (DateStringConverter) Convert(value any) (string, error) {
+	_time, err := ext.ParseDateFromAny(value)
+	if err != nil {
+		return "", fmt.Errorf("failed to cast colVal as date, colVal: '%v', err: %w", value, err)
+	}
+
+	return _time.Format(ext.PostgresDateFormat), nil
+}
diff --git a/lib/typing/values/string.go b/lib/typing/values/string.go
index 544be3a9e..472371ac3 100644
--- a/lib/typing/values/string.go
+++ b/lib/typing/values/string.go
@@ -8,6 +8,8 @@ import (
 	"strings"
 	"time"
 
+	"github.com/artie-labs/transfer/lib/typing/converters"
+
 	"github.com/artie-labs/transfer/lib/config/constants"
 	"github.com/artie-labs/transfer/lib/stringutil"
 	"github.com/artie-labs/transfer/lib/typing"
@@ -36,14 +38,17 @@ func ToString(colVal any, colKind typing.KindDetails) (string, error) {
 		return "", fmt.Errorf("colVal is nil")
 	}
 
-	switch colKind.Kind {
-	case typing.Date.Kind:
-		_time, err := ext.ParseDateFromAny(colVal)
-		if err != nil {
-			return "", fmt.Errorf("failed to cast colVal as date, colVal: '%v', err: %w", colVal, err)
-		}
+	sv, err := converters.GetStringConverter(colKind)
+	if err != nil {
+		return "", fmt.Errorf("failed to get string converter: %w", err)
+	}
+
+	// Prioritize converters
+	if sv != nil {
+		return sv.Convert(colVal)
+	}
 
-		return _time.Format(ext.PostgresDateFormat), nil
+	switch colKind.Kind {
 	case typing.Time.Kind:
 		_time, err := ext.ParseTimeFromAny(colVal)
 		if err != nil {