fix: restore screener OpenAPI constraints (WealthLedger/backend#70) (#95)

src/openapi.ts

@@ -3,9 +3,20 @@ import { DocumentBuilder, SwaggerModule } from '@nestjs/swagger';
 
 export const API_PREFIX = 'api/v1';
 
+// Nest Swagger cannot express additionalProperties on a class, so closed request
+// bodies are restored here after generation; the runtime allowlist stays in the controller.
+const CLOSED_SCHEMAS = ['StockScreenerCriteriaDto'];
+
 export function createOpenApiDocument(app: INestApplication) {
-  return SwaggerModule.createDocument(
+  const document = SwaggerModule.createDocument(
     app,
     new DocumentBuilder().setTitle('WealthLedger API').setVersion('v1').build(),
   );
+  const schemas = document.components?.schemas ?? {};
+  for (const [name, schema] of Object.entries(schemas)) {
+    if (CLOSED_SCHEMAS.includes(name) && 'properties' in schema) {
+      schema.additionalProperties = false;
+    }
+  }
+  return document;
 }