Use newtypes for operator names (#672)

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## Description

We were using `String` for these, and making some assumptions about NDCs
and OpenDD operator names being the same. This uses newtypes and
documents where these assumptions are being made. Functional no-op.

V3_GIT_ORIGIN_REV_ID: 195e55db6fadf48c956684130e23f647eaa17fb1

v3/crates/execute/src/ir/filter.rs

@@ -10,7 +10,7 @@ use serde::Serialize;
 use crate::ir::error;
 use crate::model_tracking::{count_model, UsagesCounts};
 use open_dds::{
-    data_connector::DataConnectorColumnName,
+    data_connector::{DataConnectorColumnName, DataConnectorOperatorName},
     types::{CustomTypeName, FieldName},
 };
 use schema::FilterRelationshipAnnotation;
@@ -133,7 +133,9 @@ fn build_filter_expression<'s>(
         )) => {
             let FieldMapping { column, .. } =
                 get_field_mapping_of_field_name(type_mappings, object_type, field_name)?;
+
             let mut expressions = Vec::new();
+
             for (_op_name, op_value) in field.value.as_object()? {
                 match op_value.info.generic {
                     schema::Annotation::Input(InputAnnotation::Model(
@@ -271,7 +273,7 @@ fn resolve_filter_object<'s>(
 
 /// Generate a binary comparison operator
 fn build_binary_comparison_expression(
-    operator: &str,
+    operator: &DataConnectorOperatorName,
     column: DataConnectorColumnName,
     value: &normalized_ast::Value<'_, GDS>,
 ) -> ndc_models::Expression {
@@ -281,7 +283,7 @@ fn build_binary_comparison_expression(
             path: Vec::new(),
             field_path: None,
         },
-        operator: operator.to_string(),
+        operator: operator.0.clone(),
         value: ndc_models::ComparisonValue::Scalar {
             value: value.as_json(),
         },

v3/crates/execute/src/ir/permissions.rs

@@ -4,7 +4,10 @@ use hasura_authn_core::{SessionVariableValue, SessionVariables};
 use lang_graphql::normalized_ast;
 use ndc_models;
 
-use open_dds::{data_connector::DataConnectorColumnName, types::InbuiltType};
+use open_dds::{
+    data_connector::{DataConnectorColumnName, DataConnectorOperatorName},
+    types::InbuiltType,
+};
 
 use crate::ir::error;
 use crate::model_tracking::{count_model, UsagesCounts};
@@ -167,7 +170,7 @@ pub(crate) fn process_model_predicate<'s>(
 fn make_permission_binary_boolean_expression(
     ndc_column: DataConnectorColumnName,
     argument_type: &QualifiedTypeReference,
-    operator: &str,
+    operator: &DataConnectorOperatorName,
     value_expression: &metadata_resolve::ValueExpression,
     session_variables: &SessionVariables,
     usage_counts: &mut UsagesCounts,
@@ -184,7 +187,7 @@ fn make_permission_binary_boolean_expression(
             path: Vec::new(),
             field_path: None,
         },
-        operator: operator.to_owned(),
+        operator: operator.0.clone(),
         value: ndc_models::ComparisonValue::Scalar {
             value: ndc_expression_value,
         },

v3/crates/metadata-resolve/src/helpers/argument.rs

@@ -18,8 +18,9 @@ use crate::types::subgraph::{ArgumentInfo, Qualified, QualifiedBaseType, Qualifi
 use indexmap::IndexMap;
 use ndc_models;
 use open_dds::arguments::ArgumentName;
-use open_dds::data_connector::DataConnectorName;
-use open_dds::data_connector::DataConnectorObjectType;
+use open_dds::data_connector::{
+    DataConnectorName, DataConnectorObjectType, DataConnectorOperatorName,
+};
 use open_dds::models::ModelName;
 use open_dds::permissions;
 use open_dds::types::{CustomTypeName, FieldName, OperatorName};
@@ -672,7 +673,7 @@ fn resolve_binary_operator_for_type(
     scalars: &data_connector_scalar_types::ScalarTypeWithRepresentationInfoMap,
     ndc_scalar_type: &ndc_models::ScalarType,
     subgraph: &str,
-) -> Result<(String, QualifiedTypeReference), Error> {
+) -> Result<(DataConnectorOperatorName, QualifiedTypeReference), Error> {
     let field_definition = fields
         .get(field_name)
         .ok_or_else(|| Error::TypePredicateError {
@@ -681,6 +682,7 @@ fn resolve_binary_operator_for_type(
                 type_name: type_name.clone(),
             },
         })?;
+
     let comparison_operator_definition = &ndc_scalar_type
         .comparison_operators
         .get(&operator.0)
@@ -690,12 +692,14 @@ fn resolve_binary_operator_for_type(
                 operator_name: operator.clone(),
             },
         })?;
+
     match comparison_operator_definition {
-        ndc_models::ComparisonOperatorDefinition::Equal => {
-            Ok((operator.0.clone(), field_definition.field_type.clone()))
-        }
+        ndc_models::ComparisonOperatorDefinition::Equal => Ok((
+            DataConnectorOperatorName(operator.to_string()),
+            field_definition.field_type.clone(),
+        )),
         ndc_models::ComparisonOperatorDefinition::In => Ok((
-            operator.0.clone(),
+            DataConnectorOperatorName(operator.to_string()),
             QualifiedTypeReference {
                 underlying_type: QualifiedBaseType::List(Box::new(
                     field_definition.field_type.clone(),
@@ -704,7 +708,7 @@ fn resolve_binary_operator_for_type(
             },
         )),
         ndc_models::ComparisonOperatorDefinition::Custom { argument_type } => Ok((
-            operator.0.clone(),
+            DataConnectorOperatorName(operator.to_string()),
             resolve_ndc_type(data_connector, argument_type, scalars, subgraph)?,
         )),
     }

v3/crates/metadata-resolve/src/stages/model_permissions/types.rs

@@ -3,7 +3,7 @@ use crate::types::error::{Error, RelationshipError};
 use crate::types::permission::ValueExpression;
 use crate::types::subgraph::{deserialize_qualified_btreemap, serialize_qualified_btreemap};
 use open_dds::{
-    data_connector::DataConnectorColumnName,
+    data_connector::{DataConnectorColumnName, DataConnectorOperatorName},
     models::ModelName,
     relationships::{RelationshipName, RelationshipType},
     types::CustomTypeName,
@@ -47,7 +47,7 @@ pub enum ModelPredicate {
     BinaryFieldComparison {
         field: FieldName,
         ndc_column: DataConnectorColumnName,
-        operator: String,
+        operator: DataConnectorOperatorName,
         argument_type: QualifiedTypeReference,
         value: ValueExpression,
     },

v3/crates/schema/src/model_filter.rs

@@ -1,6 +1,6 @@
 use lang_graphql::ast::common as ast;
 use lang_graphql::schema::{self as gql_schema, InputField, Namespaced};
-use open_dds::types::CustomTypeName;
+use open_dds::{data_connector::DataConnectorOperatorName, types::CustomTypeName};
 use std::collections::BTreeMap;
 
 use super::types::input_type;
@@ -79,6 +79,10 @@ pub fn build_scalar_comparison_input(
             nullable: true,
         };
 
+        // this feels a bit loose, we're depending on the fact the ast::Name and
+        // DataConnectorOperatorName should be the same
+        let ndc_operator_name = DataConnectorOperatorName(op_name.to_string());
+
         input_fields.insert(
             op_name.clone(),
             builder.allow_all_namespaced(
@@ -87,7 +91,7 @@ pub fn build_scalar_comparison_input(
                     None,
                     types::Annotation::Input(types::InputAnnotation::Model(
                         types::ModelInputAnnotation::ComparisonOperation {
-                            operator: op_name.to_string(),
+                            operator: ndc_operator_name,
                         },
                     )),
                     nullable_input_type,

v3/crates/schema/src/types.rs

@@ -12,7 +12,7 @@ use std::{
 use open_dds::{
     arguments::ArgumentName,
     commands,
-    data_connector::DataConnectorColumnName,
+    data_connector::{DataConnectorColumnName, DataConnectorOperatorName},
     models,
     types::{self},
 };
@@ -197,7 +197,7 @@ pub enum ModelInputAnnotation {
         ndc_table_argument: Option<ConnectorArgumentName>,
     },
     ComparisonOperation {
-        operator: String,
+        operator: DataConnectorOperatorName,
     },
     IsNullOperation,
     ModelOrderByExpression,