Struct LocalFileFlowTaskQueue 

pub struct LocalFileFlowTaskQueue { /* private fields */ }

JSON-backed local durable task queue.

Tasks are stored as one JSON file per pending item under <root>/pending. The queue serializes access inside the current process. It is intended for embedded hosts and local crash/restart durability of pending tasks; it does not provide cross-process locking. Heartbeats atomically rename inflight files, making the replacement file name a new fencing token and lease-age timestamp.

Implementations

impl LocalFileFlowTaskQueue

pub fn new(root: impl Into<PathBuf>) -> Self

Creates a local durable queue rooted at root.

pub fn root(&self) -> &Path

Returns the queue root directory.

pub async fn inflight_len(&self) -> Result<usize>

Returns the number of currently leased task files.

pub async fn dead_letter_len(&self) -> Result<usize>

Returns the number of dead-lettered task files.

pub async fn dead_lettered_tasks( &self, ) -> Result<Vec<LocalFileDeadLetteredTask>>

Loads dead-lettered tasks in durable file order.

pub async fn requeue_inflight_older_than( &self, cutoff: DateTime<Utc>, ) -> Result<usize>

Returns leases at or before cutoff to pending dispatch.

pub async fn dead_letter_inflight_older_than( &self, cutoff: DateTime<Utc>, reason: impl Into<String>, ) -> Result<usize>

Moves leases at or before cutoff into durable dead-letter files.

Trait Implementations

impl Clone for LocalFileFlowTaskQueue

fn clone(&self) -> LocalFileFlowTaskQueue

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for LocalFileFlowTaskQueue

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

Formats the value using the given formatter.

impl FlowTaskQueue for LocalFileFlowTaskQueue

fn enqueue<'life0, 'async_trait>( &'life0 self, task: FlowTask, ) -> Pin<Box<dyn Future<Output = Result<()>> + Send + 'async_trait>>

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

Appends one task to pending dispatch.

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

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

Leases the next pending task without acknowledging it.

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

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

Refreshes an active lease and returns its replacement fencing token.

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

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

Acknowledges the active lease identified by its latest fencing token.

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

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

Returns inflight tasks to pending dispatch and reports the count.

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

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

Returns the number of tasks pending dispatch.

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

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

Leases and immediately acknowledges the next pending task.

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

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

Returns whether no tasks are pending dispatch.