support nullable value in 'tags' in AddAction

Author: gotocoding-DB

derive-macros/src/lib.rs

@@ -119,9 +119,35 @@ fn gen_schema_fields(data: &Data) -> TokenStream {
                     }
                 });
                 if have_schema_null {
-                    if let Some(last_ident) = type_path.path.segments.last().map(|seg| &seg.ident) {
-                        if last_ident != "HashMap" {
-                           return Error::new(
+                    // Check if the type is HashMap or Option<HashMap>
+                    let last_segment = type_path.path.segments.last();
+                    let is_valid = if let Some(seg) = last_segment {
+                        let last_ident = &seg.ident;
+                        if last_ident == "HashMap" {
+                            true
+                        } else if last_ident == "Option" {
+                            // Check if Option wraps HashMap
+                            if let PathArguments::AngleBracketed(args) = &seg.arguments {
+                                args.args.iter().any(|arg| {
+                                    if let syn::GenericArgument::Type(Type::Path(inner_path)) = arg {
+                                        inner_path.path.segments.last().map(|s| &s.ident) == Some(&syn::Ident::new("HashMap", Span::call_site()))
+                                    } else {
+                                        false
+                                    }
+                                })
+                            } else {
+                                false
+                            }
+                        } else {
+                            false
+                        }
+                    } else {
+                        false
+                    };
+
+                    if !is_valid {
+                        if let Some(last_ident) = last_segment.map(|seg| &seg.ident) {
+                            return Error::new(
                                 last_ident.span(),
                                 format!("Can only use allow_null_container_values on HashMap fields, not {last_ident}")
                             ).to_compile_error()

kernel/src/actions/mod.rs

@@ -721,6 +721,7 @@ pub(crate) struct Add {
 
     /// Map containing metadata about this logical file.
     #[cfg_attr(test, serde(skip_serializing_if = "Option::is_none"))]
+    #[allow_null_container_values]
     pub tags: Option<HashMap<String, String>>,
 
     /// Information about deletion vector (DV) associated with this add action
@@ -1075,7 +1076,7 @@ mod tests {
                 StructField::nullable("stats", DataType::STRING),
                 StructField::nullable(
                     "tags",
-                    MapType::new(DataType::STRING, DataType::STRING, false),
+                    MapType::new(DataType::STRING, DataType::STRING, true),
                 ),
                 deletion_vector_field(),
                 StructField::nullable("baseRowId", DataType::LONG),

kernel/src/schema/derive_macro_utils.rs

@@ -116,3 +116,10 @@ impl<T: ToNullableContainerType> GetNullableContainerStructField for T {
         StructField::not_null(name, T::to_nullable_container_type())
     }
 }
+
+// Blanket impl for optional container types with nullable values
+impl<T: ToNullableContainerType> GetNullableContainerStructField for Option<T> {
+    fn get_nullable_container_struct_field(name: impl Into<String>) -> StructField {
+        StructField::nullable(name, T::to_nullable_container_type())
+    }
+}