Using mongodb in Angular SSR

I'm migrating code to a new Angular 19 project using hybrid rendering (SSR + client-side). When rendering on the server, I want to query MongoDB directly instead of using an API. However, I'm encountering issues setting up MongoDB, possibly related to whatwg-url.

Problem

When initializing MongoClient, I get a TypeError: Cannot convert undefined or null to object originating from whatwg-url. This happens both with a remote and local database.

Code

const mongoClient = new MongoClient(
config.CONNECTION_STRING,
{
tls: true,
tlsCAFile: join(process.cwd(), 'files', config.TLS_FILE),
}
);
const client = await mongoClient.connect();
return client.db();


Error

TypeError: Cannot convert undefined or null to object
at Function.getPrototypeOf (<anonymous>)
at node_modules/whatwg-url/lib/utils.js (.../mongodb.js:20203:41)
... (full stack trace in original question)


What I've Tried

1. Followed suggestions from this similar issue Angular 17 SSR [vite] Error when evaluating SSR module (updating whatwg-url).
2. Verified the connection string is correct (error persists even with a local DB).
3. Tested with both Angulars Express server and as an Angular service -- same error.

Suspected Cause

The whatwg-url dependency (used by MongoDB) seems to fail during SSR module evaluation. Is there a known compatibility issue or workaround for Angular 19 + Vite + MongoDB?

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