The approximate timestamp

This is either the last observed sequencer timestamp OR the effective timestamp after we observed the time difference of (effective - sequencer = epsilon) to elapse

Returns a snapshot of the current member topology for the given domain

The future will wait for the data if the data is not there yet.

Waits until a snapshot is available

Returns an optional future which will complete when the timestamp has been observed

If the timestamp is already observed, we return None.

Note that this function allows to wait for effective time (true) and sequenced time (false). If we wait for effective time, we wait until the topology snapshot for that given point in time is known. As we future date topology transactions (to avoid bottlenecks), this might be before we actually observed a sequencing timestamp.

Our current snapshot approximation

As topology transactions are future dated (to prevent sequential bottlenecks), we do have to "guess" the current state, as time is defined by the sequencer after we've sent the transaction. Therefore, this function will return the best snapshot approximation known.

The domain this client applies to

Returns a snapshot of the current member topology for the given domain. The future will log a warning and await the snapshot if the data is not there yet.

Returns the topology information at a certain point in time

Use this method if you are sure to be synchronized with the topology state updates. The method will block & wait for an update, but emit a warning if it is not available

Returns true if the topology information at the passed timestamp is already known

The most recently observed effective timestamp

The effective timestamp is sequencer_time + epsilon(sequencer_time), where epsilon is given by the topology change delay time, defined using the domain parameters.

This is the highest timestamp for which we can serve snapshots

Returns the topology information at a certain point in time

Fails with an exception if the state is not yet known.

Possibly future dated head snapshot

As we future date topology transactions, the head snapshot is our latest knowledge of the topology state, but as it can be still future dated, we need to be careful when actually using it: the state might not yet be active, as the topology transactions are future dated. Therefore, do not act towards the sequencer using this snapshot, but use the currentSnapshotApproximation instead.