From cc86e19b0fb43b51939d463bc4c748a84a79cea4 Mon Sep 17 00:00:00 2001
From: Johnny Schmidt <john.schmidt@airbyte.io>
Date: Mon, 23 Dec 2024 11:33:05 -0800
Subject: [PATCH] Destination S3V2: Fix: Avro names starting with numbers

---
 .../airbyte/cdk/load/data/Transformations.kt  |  9 +++++++-
 .../cdk/load/data/TransformationsTest.kt      | 21 +++++++++++++++++++
 2 files changed, 29 insertions(+), 1 deletion(-)
 create mode 100644 airbyte-cdk/bulk/core/load/src/test/kotlin/io/airbyte/cdk/load/data/TransformationsTest.kt

diff --git a/airbyte-cdk/bulk/core/load/src/main/kotlin/io/airbyte/cdk/load/data/Transformations.kt b/airbyte-cdk/bulk/core/load/src/main/kotlin/io/airbyte/cdk/load/data/Transformations.kt
index f3169e1e51a7..c5a82d6dc808 100644
--- a/airbyte-cdk/bulk/core/load/src/main/kotlin/io/airbyte/cdk/load/data/Transformations.kt
+++ b/airbyte-cdk/bulk/core/load/src/main/kotlin/io/airbyte/cdk/load/data/Transformations.kt
@@ -42,6 +42,13 @@ class Transformations {
                 .joinToString(separator = ".")
         }
 
-        fun toAvroSafeName(name: String) = toAlphanumericAndUnderscore(name)
+        fun toAvroSafeName(name: String): String {
+            val stripped = toAlphanumericAndUnderscore(name)
+            return if (stripped.substring(0, 1).matches("[A-Za-z_]".toRegex())) {
+                stripped
+            } else {
+                "_$stripped"
+            }
+        }
     }
 }
diff --git a/airbyte-cdk/bulk/core/load/src/test/kotlin/io/airbyte/cdk/load/data/TransformationsTest.kt b/airbyte-cdk/bulk/core/load/src/test/kotlin/io/airbyte/cdk/load/data/TransformationsTest.kt
new file mode 100644
index 000000000000..2197f534e2bd
--- /dev/null
+++ b/airbyte-cdk/bulk/core/load/src/test/kotlin/io/airbyte/cdk/load/data/TransformationsTest.kt
@@ -0,0 +1,21 @@
+/*
+ * Copyright (c) 2024 Airbyte, Inc., all rights reserved.
+ */
+
+package io.airbyte.cdk.load.data
+
+import org.junit.jupiter.api.Test
+
+class TransformationsTest {
+    @Test
+    fun `test avro illegal start character`() {
+        val unsafeName = "1d_view"
+        assert(Transformations.toAvroSafeName(unsafeName) == "_1d_view")
+    }
+
+    @Test
+    fun `test avro special characters`() {
+        val unsafeName = "1d_view!@#$%^&*()"
+        assert(Transformations.toAvroSafeName(unsafeName) == "_1d_view__________")
+    }
+}