fix: in interop-csn, remove all unknown properties from meta section (#387)

* fix: in interop-csn, remove all unknown properties

According to csn-interop spec, only certain properties are allowed in section "meta". With this change, we remove all properties that are not allowed.

For example, with version 6.8.0 cds-compiler adds new attribute "compilerCsnFlavor" to the meta section of CSN. This is not specified in interopCsn and thus is removed.

* Update lib/interopCsn.js

Co-authored-by: hyperspace-insights[bot] <209611008+hyperspace-insights[bot]@users.noreply.github.com>

---------

Co-authored-by: hyperspace-insights[bot] <209611008+hyperspace-insights[bot]@users.noreply.github.com>

Author: stewsk

__tests__/unit/__snapshots__/interopCsn.test.js.snap

@@ -12,9 +12,13 @@ exports[`interop-csn should extract service metadata 1`] = `
   "meta": {
     "__name": "MyService",
     "__namespace": "customer.namespace",
+    "__privateProperty": "shouldStay",
     "document": {
       "version": "2.0.0",
     },
+    "features": {
+      "complete": true,
+    },
     "flavor": "effective",
   },
 }

__tests__/unit/interopCsn.test.js

@@ -52,6 +52,15 @@ describe("interop-csn", () => {
             definitions: {
                 "customer.namespace.MyService.v2": { kind: "service" },
             },
+            meta: {
+              creator: "shouldVanish",
+              compilerCsnFlavor: "shouldVanish",
+              unknownProp: "shouldVanish",
+              __privateProperty: "shouldStay",
+              features: {
+                "complete": true
+              },
+            }
         };
         expect(interopCSN(csn)).toMatchSnapshot();
     });

lib/interopCsn.js

@@ -132,10 +132,18 @@ function map_annotations(csn) {
 function add_meta_info(csn) {
     if (typeof csn != "object") return csn; // needed to make tests pass
     csn["csnInteropEffective"] = "1.0";
-    csn.meta ??= {};
+    csn.meta ??= {};  // ensure there is a meta section
+
+    // Keep only the properties of csn.meta that are relevant for interop:
+    //   "flavor", "document", "features", and private extension names (starting with "__")
+    // Remove everything else, including "creator" (leaks build details) and
+    // any unknown compiler-added properties (e.g. "compilerCsnFlavor").
+    for (let k in csn.meta) {
+        if (!["flavor", "document", "features"].includes(k) && !k.startsWith("__")) {
+            delete csn.meta[k];
+        } 
+    }
     csn.meta.flavor = "effective";
-    // Remove compiler creator information – not relevant for ORD interop and leaks build details
-    if (csn.meta.creator) delete csn.meta.creator;
 
     let services = Object.entries(csn.definitions).filter(([, def]) => def.kind === "service");
     if (services.length === 1) {