Struct ConsumerGroup 

pub struct ConsumerGroup {
    pub group_id: String,
    pub members: HashMap<SubscriberId, HashSet<String>>,
    pub committed_offsets: HashMap<String, u64>,
    pub created_at: u64,
}

A consumer group that coordinates message consumption across multiple subscribers.

Each member is assigned a set of channels, and the group tracks committed offsets per channel so that consumers can resume from where they left off.

Fields

group_id: String

Unique identifier for this consumer group.

members: HashMap<SubscriberId, HashSet<String>>

Map of subscriber_id -> set of assigned channel names.

committed_offsets: HashMap<String, u64>

Map of channel_name -> committed offset.

created_at: u64

Timestamp when the group was created.

Implementations

impl ConsumerGroup

pub fn new(group_id: impl Into<String>) -> Self

Create a new consumer group with the given ID.

pub fn add_member( &mut self, subscriber_id: SubscriberId, channels: HashSet<String>, )

Add a member to the consumer group with an initial set of assigned channels.

pub fn remove_member( &mut self, subscriber_id: &SubscriberId, ) -> Option<HashSet<String>>

Remove a member from the consumer group. Returns the channels that were assigned to the removed member, or None if the member was not found.

pub fn commit_offset(&mut self, channel_name: impl Into<String>, offset: u64)

Commit an offset for a channel. This records the position up to which messages have been successfully processed.

pub fn get_offset(&self, channel_name: &str) -> Option<u64>

Get the committed offset for a channel. Returns None if no offset has been committed for that channel.

pub fn member_count(&self) -> usize

Get the number of members in the group.

pub fn is_member(&self, subscriber_id: &SubscriberId) -> bool

Check if a subscriber is a member of this group.

pub fn get_member_channels( &self, subscriber_id: &SubscriberId, ) -> Option<&HashSet<String>>

Get the channels assigned to a specific member.

Trait Implementations

impl Clone for ConsumerGroup

fn clone(&self) -> ConsumerGroup

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ConsumerGroup

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.