Struct InMemoryEventLog 

pub struct InMemoryEventLog { /* private fields */ }

In-memory implementation of the EventLog trait

Uses a Vec for storage and a Notify for waking subscribers when new events are appended. Thread-safe via Arc<RwLock>.

Performance

• Append: O(1) amortized
• Subscribe replay: O(n) from start position
• Ack/Seek: O(1)

Limitations

• Events are lost on restart (no persistence)
• Memory grows unbounded (no retention policy yet)
• Single-instance only (no cross-process sharing)

Implementations

impl InMemoryEventLog

pub fn new() -> Self

Create a new empty in-memory event log

Trait Implementations

impl Clone for InMemoryEventLog

fn clone(&self) -> InMemoryEventLog

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for InMemoryEventLog

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

Formats the value using the given formatter.

impl Default for InMemoryEventLog

fn default() -> Self

Returns the “default value” for a type.

impl EventLog for InMemoryEventLog

fn append<'life0, 'async_trait>( &'life0 self, envelope: EventEnvelope, ) -> Pin<Box<dyn Future<Output = Result<SeqNo>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Append an event envelope to the log

fn subscribe<'life0, 'life1, 'async_trait>( &'life0 self, consumer: &'life1 str, position: SeekPosition, ) -> Pin<Box<dyn Future<Output = Result<Pin<Box<dyn Stream<Item = EventEnvelope> + Send>>>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Subscribe to events from a given position

fn ack<'life0, 'life1, 'async_trait>( &'life0 self, consumer: &'life1 str, seq_no: SeqNo, ) -> Pin<Box<dyn Future<Output = Result<()>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Acknowledge that a consumer has processed up to a sequence number

fn seek<'life0, 'life1, 'async_trait>( &'life0 self, consumer: &'life1 str, position: SeekPosition, ) -> Pin<Box<dyn Future<Output = Result<()>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Seek a consumer to a new position

fn last_seq_no<'life0, 'async_trait>( &'life0 self, ) -> Pin<Box<dyn Future<Output = Option<SeqNo>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Get the current last sequence number in the log