Struct L2Cache 

pub struct L2Cache { /* private fields */ }

L2 Cache using Redis with ConnectionManager for automatic reconnection

Implementations

impl L2Cache

pub async fn new() -> Result<Self>

Create new L2 cache with ConnectionManager for automatic reconnection

pub async fn get(&self, key: &str) -> Option<Value>

Get value from L2 cache using persistent ConnectionManager

pub async fn get_with_ttl(&self, key: &str) -> Option<(Value, Option<Duration>)>

Get value with its remaining TTL from L2 cache

Returns tuple of (value, ttl_seconds) if key exists TTL is in seconds, None if key doesn’t exist or has no expiration

pub async fn set_with_ttl( &self, key: &str, value: Value, ttl: Duration, ) -> Result<()>

Set value with custom TTL using persistent ConnectionManager

pub async fn remove(&self, key: &str) -> Result<()>

Remove value from cache using persistent ConnectionManager

pub async fn health_check(&self) -> bool

Health check

pub async fn stream_add( &self, stream_key: &str, fields: Vec<(String, String)>, maxlen: Option<usize>, ) -> Result<String>

Publish data to Redis Stream using XADD

Arguments

• stream_key - Name of the Redis Stream (e.g., “events_stream”)
• fields - Vec of field-value pairs to add to the stream
• maxlen - Optional maximum length for stream trimming (uses MAXLEN ~ for approximate trimming)

Returns

The stream entry ID generated by Redis (e.g., “1234567890123-0”)

pub async fn stream_read_latest( &self, stream_key: &str, count: usize, ) -> Result<Vec<(String, Vec<(String, String)>)>>

Read latest entries from Redis Stream using XREVRANGE

Arguments

• stream_key - Name of the Redis Stream
• count - Number of latest entries to retrieve

Returns

Vector of (entry_id, fields) tuples, ordered from newest to oldest

pub async fn stream_read( &self, stream_key: &str, last_id: &str, count: usize, block_ms: Option<usize>, ) -> Result<Vec<(String, Vec<(String, String)>)>>

Read entries from Redis Stream using XREAD (blocking or non-blocking)

Arguments

• stream_key - Name of the Redis Stream
• last_id - Last entry ID seen (use “0” to read from beginning, “$” for only new entries)
• count - Maximum number of entries to retrieve
• block_ms - Optional blocking timeout in milliseconds (None for non-blocking)

Returns

Vector of (entry_id, fields) tuples

Trait Implementations

impl CacheBackend for L2Cache

Implement CacheBackend trait for L2Cache

This allows L2Cache to be used as a pluggable backend in the multi-tier cache system.

fn get<'life0, 'life1, 'async_trait>( &'life0 self, key: &'life1 str, ) -> Pin<Box<dyn Future<Output = Option<Value>> + Send + 'async_trait>>

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

Get value from cache by key

fn set_with_ttl<'life0, 'life1, 'async_trait>( &'life0 self, key: &'life1 str, value: Value, ttl: Duration, ) -> Pin<Box<dyn Future<Output = Result<()>> + Send + 'async_trait>>

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

Set value in cache with time-to-live

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

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

Remove value from cache

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

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

Check if cache backend is healthy

fn name(&self) -> &str

Get the name of this cache backend

impl L2CacheBackend for L2Cache

Implement L2CacheBackend trait for L2Cache

This extends CacheBackend with TTL introspection capabilities needed for L2->L1 promotion.

fn get_with_ttl<'life0, 'life1, 'async_trait>( &'life0 self, key: &'life1 str, ) -> Pin<Box<dyn Future<Output = Option<(Value, Option<Duration>)>> + Send + 'async_trait>>

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

Get value with its remaining TTL from L2 cache

impl StreamingBackend for L2Cache

Implement StreamingBackend trait for L2Cache

This enables Redis Streams functionality for event-driven architectures.

fn stream_add<'life0, 'life1, 'async_trait>( &'life0 self, stream_key: &'life1 str, fields: Vec<(String, String)>, maxlen: Option<usize>, ) -> Pin<Box<dyn Future<Output = Result<String>> + Send + 'async_trait>>

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

Add an entry to a stream

fn stream_read_latest<'life0, 'life1, 'async_trait>( &'life0 self, stream_key: &'life1 str, count: usize, ) -> Pin<Box<dyn Future<Output = Result<Vec<(String, Vec<(String, String)>)>>> + Send + 'async_trait>>

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

Read the latest N entries from a stream (newest first)

fn stream_read<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, stream_key: &'life1 str, last_id: &'life2 str, count: usize, block_ms: Option<usize>, ) -> Pin<Box<dyn Future<Output = Result<Vec<(String, Vec<(String, String)>)>>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait,

Read entries from a stream with optional blocking