Steemit API Question

I'm trying to import blocks from the chain immediately as they are posted. I'm tired of waiting a full minute before I can see what's being posted to the platform.

One tutorial said this:

const stream = client.blockchain.getOperationsStream({ mode: BlockchainMode.Latest })

This threw an error for me using javascript.

Another tutorial says this:

const stream = client.blockchain.getOperationsStream({mode: dsteem.BlockchainMode.Latest})

This doesn't throw an error in JavaScript, but it also doesn't work.

Does anyone know?

You'd think the most basic things you could do would be documented.
Guess not.