feat(introspection): add parents

Author: della-90

src/introspection/introspection.ts

@@ -137,8 +137,8 @@ function simplifySchema(schema: GraphQLSchema): SimplifiedIntrospection {
 	return {
 		types: mapValues(schema.getTypeMap(), (type) => convertType(schema, type)),
 		queryType: schema.getQueryType().name,
-		mutationType: schema.getMutationType().name ?? null,
-		subscriptionType: schema.getSubscriptionType().name ?? null,
+		mutationType: schema.getMutationType()?.name ?? null,
+		subscriptionType: schema.getSubscriptionType()?.name ?? null,
 		//FIXME:
 		//directives:
 	};
@@ -209,13 +209,63 @@ function assignTypesAndIDs(schema: SimplifiedIntrospection) {
 }
 
 function addParent(schema: SimplifiedIntrospection) {
-	return schema;
+	function extractFields(type) {
+		// no need to inspect circular types any further
+		if (type.type === "[Circular]") return [type];
+
+		// same with scalars and enums
+		if (_.includes(["SCALAR", "ENUM"], type.kind && type.kind)) return [];
+		if (
+			type.type &&
+			type.type.kind &&
+			_.includes(["SCALAR", "ENUM"], type.type.kind)
+		)
+			return [];
+
+		return _.flatMap(_.values(type.fields), (currentType) => {
+			// if it's a composite object, use recursion to introspect the inner object
+			const innerTypes = currentType.type.fields
+				? _.flatMap(currentType.type.fields, (subType) =>
+						extractFields(subType)
+				  )
+				: [currentType];
+			// dedupe types by their id
+			return _.uniqBy(_.concat(innerTypes, currentType), (x) => x.id);
+		});
+	}
+
+	const allFields = _.flatMap(_.values(schema.types), (type) =>
+		extractFields(type)
+	);
+
+	/*
+	 * Group fields by their corresponding type id
+	 */
+	const groupedFieldsByType = _.groupBy(allFields, function (field) {
+		return field.type.id;
+	});
+
+	/*
+	 * Extract id and prepare the mapping
+	 */
+	const mappings = _.mapValues(groupedFieldsByType, function (t) {
+		return _.map(t, (field) => field.id);
+	});
+
+	/*
+	 * Assign the mapping
+	 */
+	_.each(Object.keys(schema.types), (type) => {
+		if (mappings[type]) {
+			(schema.types[type] as any).parents = mappings[type];
+		}
+	});
 }
 
 export function getSchema(schema: GraphQLSchema) {
 	const simpleSchema = simplifySchema(schema);
 	assignTypesAndIDs(simpleSchema);
-	addParent(simpleSchema);
+	// addParent(simpleSchema);
 
 	// Force cast to the correct type
 	// FIXME: This is not the right way of doing it