Write an acknowledgement that member has processed earlier timestamps. Only the latest timestamp needs to be stored. Earlier timestamps can be overwritten. Acknowledgements of earlier timestamps should be ignored.

This takes the timestamp that is considered safe to prune from and walks it back to ensure that we have retained enough events to be able to start subscriptions from the counter checkpoint immediately preceding the timestamp.

Count records currently stored by the sequencer. Used for pruning tests.

No implementation as only required for crash recovery

Prevents member from sending and reading from the sequencer, and allows unread data for this member to be pruned. It however won't stop any sends addressed to this member.

Evict unauthenticated member from the cache.

Fetch a checkpoint with a counter value less than the provided counter.

Fetch the lower bound of events that can be read. Returns None if all events can be read.

There can be no other sequencers sharing this storage

Read the watermark for this sequencer and its online/offline status. Currently only used for testing.

Flag that we're going offline (likely due to a shutdown)

Mark the sequencer as online and return a timestamp for when this sequencer can start safely producing events.

Check whether the member is enabled. Currently used when receiving a request for reading.

Return the latest acknowledgements for all members

Locate a timestamp relative to the earliest available event based on a skip index starting at 0. Useful to monitor the progress of pruning and for pruning in batches.

Lookup an existing member id for the given member. Will return a cached value if available. Return scala.None if no id exists.

Lookup member directly without caching.

This store does not support multiple concurrent instances so will do nothing.

Prune as much data as safely possible from before the given timestamp.

Prune counter checkpoints for the given member before the given timestamp.

Prune events before the given timestamp

Prune payloads before the given timestamp

Read all events of which a member is a recipient from the provided timestamp but no greater than the earliest watermark.

Register the provided member. Should be idempotent if member is already registered and return the existing id.

Save a checkpoint that as of a certain timestamp the member has this counter value. Any future subscriptions can then use this as a starting point for serving their event stream rather than starting from 0.

Save a series of events to the store. Callers should determine batch size. No batching is done within the store. Callers MUST ensure that event-ids are unique as no errors will be returned if a duplicate is present (for the sequencer writer see sequencer.PartitionedTimestampGenerator for use with their instance index).

Save an updated lower bound of events that can be read. Must be equal or greater than any prior set lower bound.

Save a series of payloads to the store. Is up to the caller to determine a reasonable batch size and no batching is done within the store.

Write the watermark that we promise not to write anything earlier than. Does not indicate that there is an event written by this sequencer for this timestamp as there may be no activity at the sequencer, but updating the timestamp allows the sequencer to indicate that it's still alive. Return an error if we find our sequencer is offline.

Build a status object representing the current state of the sequencer.

Unregister a disabled unauthenticated member. This should delete the member from the store.

Validate that the commit mode of a session is inline with the configured expected commit mode. Return a human readable message about the mismatch in commit modes if not.