fix(mongoose): transform _all_ objectID fields to string

src/collections/match/operations/match-transfer-item.operation.ts

@@ -94,9 +94,7 @@ export class MatchTransferItemOperation implements Operation {
     const customerItem = activeCustomerItems[0];
 
     const receiverUserMatch = receiverUserMatches.find((userMatch) =>
-      // eslint-disable-next-line @typescript-eslint/ban-ts-comment
-      // @ts-ignore
-      userMatch.expectedItems.includes(String(customerItem.item)),
+      userMatch.expectedItems.includes(customerItem?.item as string),
     );
 
     if (!receiverUserMatch) {

src/storage/mongoDb/mongoDb.spec.ts

@@ -0,0 +1,34 @@
+import "mocha";
+import chai from "chai";
+import chaiAsPromised from "chai-as-promised";
+import { expect } from "chai";
+import { MongooseModelCreator } from "./mongoose-schema-creator";
+import { ObjectId } from "mongodb";
+
+chai.use(chaiAsPromised);
+
+describe("MongooseModelCreator", () => {
+  describe("transformObject", () => {
+    it("should convert objectIDs in objects to strings", () => {
+      const input = {
+        _id: new ObjectId(),
+        user: new ObjectId(),
+        items: [new ObjectId(), new ObjectId()],
+      };
+      const expectedOutput = {
+        id: input._id.toString(),
+        user: input.user.toString(),
+        items: input.items.map((item) => item.toString()),
+      };
+      MongooseModelCreator.transformObject(input, undefined);
+      expect(input).to.deep.eq(expectedOutput);
+    });
+
+    it("should convert objectIDs in an array to strings", () => {
+      const input = [new ObjectId(), new ObjectId()];
+      const expectedOutput = input.map((item) => item.toString());
+      MongooseModelCreator.transformObject(input, undefined);
+      expect(input).to.deep.eq(expectedOutput);
+    });
+  });
+});

src/storage/mongoDb/mongoose-schema-creator.ts

@@ -81,17 +81,31 @@ export class MongooseModelCreator<T> {
       ret.forEach((document) =>
         MongooseModelCreator.transformObject({}, document),
       );
+      for (let i = 0; i < ret.length; i++) {
+        const value = ret[i];
+        if (value instanceof mongoose.Types.ObjectId) {
+          ret[i] = value.toString();
+        }
+      }
     } else if (typeof ret === "object") {
       const document = ret as Record<string, unknown>;
       // Translate _id to id only if id does not already exist
       // (embedded documents such as BlDocument.user may have an id field which is different from the _id field)
       if ("_id" in document && !("id" in document))
         document["id"] = document["_id"];
-      if (document["id"] instanceof mongoose.Types.ObjectId) {
-        document["id"] = document["id"].toString();
-      }
       delete document["_id"];
       delete document["__v"];
+      for (const key of Object.keys(document)) {
+        const value = document[key];
+        if (value instanceof mongoose.Types.ObjectId) {
+          document[key] = value.toString();
+        }
+        if (Array.isArray(value)) {
+          document[key] = value.map((entry) =>
+            entry instanceof mongoose.Types.ObjectId ? entry.toString() : entry,
+          );
+        }
+      }
     }
   }
 }