rxdb-server replication endpoint user data is not refreshed for query modifier

[HRM]

Im using rxdb-server with the according replication plugin. An issue I noticed is when I change the auth data of a user, the data sent by the pull stream doesn't reflect the change. I found the source of the behaviour below.

rxdb-server\src\plugins\server\endpoint-replication.ts 179-235

this.server.adapter.get(this.server.serverApp, '/' + this.urlPath + '/pullStream', async (req, res) => {

            const authData = await getAuthDataByRequest<AuthType, any, any>(this.server, req, res);
            if (!authData) { return; }

            adapter.setSSEHeaders(res);
            const docDataMatcherStream = getDocAllowedMatcher(this, ensureNotFalsy(authData));
            const subscription = replicationHandler.masterChangeStream$.pipe(
                mergeMap(async (changes) => {
                    /**
                     * The auth-data might be expired
                     * so we re-run the auth parsing each time
                     * before emitting an event.
                     */
                    let authData: RxServerAuthData<AuthType>;
                    try {
                        authData = await server.authHandler(adapter.getRequestHeaders(req));
                    } catch (err) {
                        adapter.closeConnection(res, 401, 'Unauthorized');
                        return null;
                    }

                    if (changes === 'RESYNC') {
                        return changes;
                    } else {
                        const useDocs = changes.documents.filter(d => docDataMatcherStream(d as any));
                        return {
                            documents: useDocs,
                            checkpoint: changes.checkpoint
                        };
                    }
                }),
                filter(f => f !== null && (f === 'RESYNC' || f.documents.length > 0))
            ).subscribe(filteredAndModified => {
                if (filteredAndModified === 'RESYNC') {
                    adapter.responseWrite(res, 'data: ' + JSON.stringify(filteredAndModified) + '\n\n');
                } else {
                    const responseDocuments = ensureNotFalsy(filteredAndModified).documents.map(d => removeServerOnlyFields(d as any));
                    adapter.responseWrite(
                        res,
                        'data: ' + JSON.stringify({
                            documents: responseDocuments,
                            checkpoint: ensureNotFalsy(filteredAndModified).checkpoint
                        }) + '\n\n'
                    );
                }

            });

So, we create the docDataMatcherStream at the beginning of the event stream and we don't change it till the request closes. My question would be: Are there any reasons why the docDataMatcherStream is not updated? We retrieve the authData for every change anyway.

If updateing the docDataMatcherStream is a fine approach and the behaviour wouldn't contradict anything, I would create a fix for this issue.

[pubkey]

We retrieve the authData for every change anyway.

I do not understand. The authData is send to the SSE endpoint once, it will not be send when changed or does it?

[HRM]

under the comment "The auth-data might be expired..." the auth data is reloaded (with the same request data). If I understand it correctly it is reloaded every time, we receive a change on masterChangeStream$. We reload it to see if the request is still valid. My problem is that docDataMatcherStream is not updated, so if we have a more granular access change, like the user gets ccess to new objects, the pull stream won't reflect this new state.

[pubkey]

No, this will only account for ttls of the auth data. It will not magically get new updated auth data from the client.
If your auth changes, just restart the replication.

[HRM]

Yeah sorry by the way I didn't open this as an issue, it was sad that before contributing feature changes, the contributor should open an issue for it. It just seems to me that recomputing docDataMatcherStream is a low hanging fruit as we already recompute the auth data required for it. This wouldn't allow the automatic handling of auth data change of course, it would only allow to extend the auth data in some scenarios (I'm in a scenario where it would help). Maybe It would also match a bit better how checkpoint iteration reacts to auth data change, as the next cycle there is done with the new auth data if it changes. But as another point of view, it seems to me that changing auth data is a bit of an anti-pattern, only using an id as auth data and denormalizing any other access to the stored objects is the correct way to go, and that way it doesn't necessarily makes sense to change one undefined behaviour to another.

[pubkey]

Computing the auth data is easy, so we do that. SEE are one-directional things, we do not have client-side-updated authData without manually sending it again or reopening the stream.

[stale]

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