Inferring operationID from get transactions stream data

I guess that should work but depending on the sdk you should be also able to somehow access the id directly. Here are two options for the js-sdk:

1) You can get operations from the transaction object and access its properties.

horizon.transactions()
        .cursor('now')
        .stream({
            onmessage: async function (tx) {
                let operations = await tx.operations();
                console.log(operations.records[0].id);
            }
        });

2) You could subscribe directly to operations instead of transactions.

horizon.operations()
        .cursor('now')
        .stream({
            onmessage: function (op) {
                console.log(op.id);
            }
        });