Node bridge memory cleanup

[aramikm]

Goal

The goal of this PR is to implement an automated memory cleanup mechanism that might help free the memory in cases that the uses forget to manually free it.

Closes #128

[JoeCap08055]

Looks good--have you done any testing to see if the finalizer actually does anything?

[aramikm]

I've done testing but was not able to trigger that. It seems like it's not easy triggering it in Node. If you have any ideas how we might be able to force it to trigger I'm open to ideas.

[saraswatpuneet]

I was not able to reproduce it either , it has weird behavior and unpredictable it will be worth running a load test and let it wait to see if it ever gets triggered

[aramikm]

@JoeCap08055 @saraswatpuneet I was able to verify it by directly calling global.gc inside an app which triggers cleanup.
Running following code with following command

node --expose-gc dist/index.js

function interactWithGraph() {
    const environment: EnvironmentInterface =  {environmentType: EnvironmentType.Mainnet};
    for(let i=0;i<10; i++) {
        const graph= new Graph(environment);

        let public_follow_graph_schema_id = graph.getSchemaIdFromConfig(environment, ConnectionType.Follow, PrivacyType.Public);

        let connect_action: ConnectAction = {
            type: "Connect",
            ownerDsnpUserId: "1",
            connection: {
                dsnpUserId: "2",
                schemaId: public_follow_graph_schema_id,
            } as Connection,
            dsnpKeys: {
                dsnpUserId: "2",
                keysHash: 100,
                keys: [],
            } as DsnpKeys,
        } as ConnectAction;

        let actions = [] as Action[];
        actions.push(connect_action);

        let applied = graph.applyActions(actions);
        console.log(applied);

        let connections_including_pending = graph.getConnectionsForUserGraph("1", public_follow_graph_schema_id, true);
        console.log(connections_including_pending);

        let exported = graph.exportUpdates();
        console.log(exported);
    }
    if (global.gc) {
        global.gc();
    } else {
        console.log('Garbage collection unavailable.  Pass --expose-gc '
            + 'when launching node to enable forced garbage collection.');
    }
}

which printed

freeing 8
freeing 7
freeing 6
freeing 5
freeing 4
freeing 3
freeing 2
freeing 1
freeing 0

[saraswatpuneet]

Thats a cool thing to know 🥇

[saraswatpuneet]

👍🏽