fix: BQ/proto schema names should be compared lowercase

google-cloud-bigquerystorage/src/main/java/com/google/cloud/bigquery/storage/v1/JsonToProtoMessage.java

@@ -124,7 +124,7 @@ private static DynamicMessage convertJsonToProtoMessageImpl(
       if (tableSchema != null) {
         // protoSchema is generated from tableSchema so their field ordering should match.
         fieldSchema = tableSchema.get(field.getIndex());
-        if (!fieldSchema.getName().equals(field.getName())) {
+        if (!fieldSchema.getName().toLowerCase().equals(field.getName())) {
           throw new ValidationException(
               "Field at index "
                   + field.getIndex()

google-cloud-bigquerystorage/src/main/java/com/google/cloud/bigquery/storage/v1beta2/JsonToProtoMessage.java

@@ -123,7 +123,7 @@ private static DynamicMessage convertJsonToProtoMessageImpl(
       if (tableSchema != null) {
         // protoSchema is generated from tableSchema so their field ordering should match.
         fieldSchema = tableSchema.get(field.getIndex());
-        if (!fieldSchema.getName().equals(field.getName())) {
+        if (!fieldSchema.getName().toLowerCase().equals(field.getName())) {
           throw new ValidationException(
               "Field at index "
                   + field.getIndex()

google-cloud-bigquerystorage/src/test/java/com/google/cloud/bigquery/storage/v1/JsonToProtoMessageTest.java

@@ -552,6 +552,24 @@ public void testNumericMismatch() throws Exception {
     }
   }
 
+  @Test public void testMixedCasedFieldNames() throws Exception {
+    TableFieldSchema field = TableFieldSchema
+      .newBuilder()
+      .setName("fooBar")
+      .setType(TableFieldSchema.Type.STRING)
+      .setMode(TableFieldSchema.Mode.NULLABLE)
+      .build();
+    TableSchema tableSchema = TableSchema.newBuilder().addFields(field).build();
+
+    JSONObject json = new JSONObject();
+    json.put("fooBar", "hello");
+
+    DynamicMessage protoMsg = JsonToProtoMessage.convertJsonToProtoMessage(
+      TestMixedCaseFieldNames.getDescriptor(), tableSchema, json
+    );
+
+  }
+
   @Test
   public void testBigNumericMismatch() throws Exception {
     TableFieldSchema field =

google-cloud-bigquerystorage/src/test/proto/jsonTest.proto

@@ -156,3 +156,7 @@ message TestNumeric {
 message TestBignumeric {
   repeated bytes bignumeric = 1;
 }
+
+message TestMixedCaseFieldNames {
+  required string foobar = 1;
+}