Struct AttributeMap 

pub struct AttributeMap<T> { /* private fields */ }

Defines keyed durable values sharing one Attribute name.

Each instance identifies an independent stored value and lock. Add the map definition once to crate::PersistenceSchema; pass an instance name on each access.

Implementations

impl<T> AttributeMap<T>

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

Defines an unindexed Attribute map with stable name.

pub fn indexed(self, index: AttributeIndex) -> Self

Enables search indexing for every instance using the selected index type.

pub fn sync_to_attribute_store(self) -> Self

Enables asynchronous latest-state projection for every AttributeMap instance.

Each instance maps by its physical Attribute name. The Flow must select a server-configured stores with FlowConfig::attribute_store_names. Deletions project SQL NULL, and projection failures never roll back Flow Attribute writes.

pub fn get(&self, context: &Context, instance: &str) -> HandlerResult<Option<T>>

where T: Value,

Reads one instance, returning Ok(None) when it is absent.

Errors

Returns HandlerError when the payload cannot be decoded.

pub fn get_required( &self, context: &Context, instance: &str, ) -> HandlerResult<T>

where T: Value,

Reads one instance and treats absence as an error.

Errors

Returns HandlerError when the instance is missing or cannot be decoded.

pub fn set( &self, context: &mut Context, instance: &str, value: T, ) -> HandlerResult<()>

where T: Value,

Stages one instance value for durable persistence.

Errors

Returns HandlerError when the value cannot be encoded or indexed.

pub fn delete(&self, context: &mut Context, instance: &str) -> HandlerResult<()>

Stages deletion of one instance; missing instances are valid.

pub fn map_size(&self, context: &Context) -> HandlerResult<usize>

Returns the effective number of instances, including buffered writes.

pub fn all_instance_keys(&self, context: &Context) -> HandlerResult<Vec<String>>

Returns decoded effective instance keys in ascending string order.

pub fn lock(&self, instance: impl Into<String>) -> AttributeLock

Creates a lock request scoped to one map instance.

Trait Implementations

impl<T> Clone for AttributeMap<T>

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.