Struct UntrackedValue 

pub struct UntrackedValue<T>
where
    T: Default + Send + Sync,
{ /* private fields */ }

Available on crate feature graph only.

Transient runtime value excluded from checkpoints.

UntrackedValue<T> stores a value that is intentionally omitted from checkpoint persistence. When a workflow resumes from a checkpoint, any UntrackedValue field will be initialized to T::default() regardless of what value it held before the checkpoint was created.

This is useful for caching intermediate computation results, holding open file handles or connections, or any runtime-only state that should not inflate checkpoint size.

Custom Serialization

UntrackedValue implements Serialize by always serializing as null, and Deserialize by always producing T::default(). This ensures checkpoint round-trips correctly reset the value.

Example

use adk_graph::functional::UntrackedValue;

let mut cache: UntrackedValue<Vec<String>> = UntrackedValue::new();
cache.set(vec!["cached_result".to_string()]);
assert_eq!(cache.get().len(), 1);

// After checkpoint round-trip, value resets to default
let serialized = serde_json::to_string(&cache).unwrap();
let restored: UntrackedValue<Vec<String>> = serde_json::from_str(&serialized).unwrap();
assert!(restored.get().is_empty());

Implementations

impl<T> UntrackedValue<T>

where T: Default + Send + Sync,

pub fn new() -> UntrackedValue<T>

Available on crate feature functional only.

Create a new UntrackedValue initialized to T::default().

pub fn with_value(value: T) -> UntrackedValue<T>

Available on crate feature functional only.

Create a new UntrackedValue with an initial value.

pub fn get(&self) -> &T

Available on crate feature functional only.

Get a reference to the contained value.

pub fn set(&mut self, value: T)

Available on crate feature functional only.

Set the contained value.

pub fn take(&mut self) -> T

Available on crate feature functional only.

Take the value, replacing it with T::default().

Trait Implementations

impl<T> Clone for UntrackedValue<T>

where T: Clone + Default + Send + Sync,

fn clone(&self) -> UntrackedValue<T>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<T> Debug for UntrackedValue<T>

where T: Debug + Default + Send + Sync,

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

Formats the value using the given formatter.

impl<T> Default for UntrackedValue<T>

where T: Default + Send + Sync,

fn default() -> UntrackedValue<T>

Returns the “default value” for a type.

impl<'de, T> Deserialize<'de> for UntrackedValue<T>

where T: Default + Send + Sync,

Custom deserialization: always produces T::default() regardless of input.

fn deserialize<D>( deserializer: D, ) -> Result<UntrackedValue<T>, <D as Deserializer<'de>>::Error>

where D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl<T> Serialize for UntrackedValue<T>

where T: Default + Send + Sync,

Custom serialization: always serializes as null to exclude from checkpoints.

fn serialize<S>( &self, serializer: S, ) -> Result<<S as Serializer>::Ok, <S as Serializer>::Error>

where S: Serializer,

Serialize this value into the given Serde serializer.