Struct ConsumerGroupManager 

pub struct ConsumerGroupManager { /* private fields */ }

Owns all consumer groups for a single CDC ring.

Provides the full group lifecycle: creation, per-consumer reads, acknowledgement, pending-entry inspection, ownership transfer (claim), and gap detection.

Implementations

impl ConsumerGroupManager

pub fn new(default_idle_timeout: Duration) -> Self

Create a manager whose newly created groups use default_idle_timeout for pending-entry redelivery.

pub fn create_group( &mut self, name: &str, start_seq: u64, ) -> Result<(), ConsumerGroupError>

Create a consumer group that begins delivering events at start_seq.

Returns ConsumerGroupError::GroupExists if name is already taken.

pub fn read_group( &mut self, ring: &CdcRing, group_name: &str, consumer_name: &str, count: usize, ) -> Result<GroupReadResult, ConsumerGroupError>

Deliver up to count events to consumer_name within group_name.

Before reading fresh events from the ring, timed-out pending entries owned by other consumers are reclaimed and delivered first. The consumer is auto-created if it does not already exist.

pub fn ack( &mut self, group_name: &str, seqs: &[u64], ) -> Result<usize, ConsumerGroupError>

Acknowledge one or more events by sequence number.

Acknowledged entries are removed from every consumer’s pending list within the group. Returns the total number of entries removed.

pub fn pending( &self, group_name: &str, ) -> Result<Vec<PendingSummary>, ConsumerGroupError>

Return a snapshot of every pending entry across all consumers in the group, sorted by sequence number.

pub fn claim( &mut self, group_name: &str, target_consumer: &str, min_idle: Duration, seqs: &[u64], ) -> Result<Vec<u64>, ConsumerGroupError>

Transfer ownership of pending entries to target_consumer.

Only entries whose idle time meets or exceeds min_idle are transferred. Returns the sequence numbers that were claimed.

pub fn has_group(&self, name: &str) -> bool

Return true if a group with the given name exists.

pub fn group_count(&self) -> usize

Return the number of registered groups.

pub fn check_gap( &mut self, ring: &CdcRing, group_name: &str, consumer_name: &str, ) -> Result<bool, ConsumerGroupError>

Check whether consumer_name in group_name has fallen behind the ring.

Returns true if the consumer’s last acknowledged sequence has been evicted from the ring, or if the consumer was already marked for resync.

Trait Implementations

impl Default for ConsumerGroupManager

fn default() -> Self

Returns the “default value” for a type.