Trait Store 

pub trait Store {
    // Required methods
    async fn append(&mut self, record: &[u8]) -> Result<()>;
    async fn peek(&self) -> Result<Option<Vec<u8>>>;
    async fn pop(&mut self) -> Result<Option<Vec<u8>>>;
    async fn len(&self) -> Result<usize>;

    // Provided method
    async fn is_empty(&self) -> Result<bool> { ... }
}

A durable, first-in first-out queue for store-and-forward buffering.

Records are appended while a device is offline and drained in order when a link becomes available, letting applications tolerate intermittent connectivity without losing data.

Required Methods

async fn append(&mut self, record: &[u8]) -> Result<()>

Appends a record to the back of the queue.

Arguments

• record - the raw bytes to persist.

Returns

Ok(()) once the record is durably stored.

Errors

Returns Error::Io if the record cannot be written to durable storage.

async fn peek(&self) -> Result<Option<Vec<u8>>>

Returns the oldest record without removing it.

This lets a forwarder send a record before committing to its removal, so a failed send can leave the record buffered in order rather than dropping it.

Returns

Some(record) containing the oldest buffered bytes, or None if the queue is empty.

Errors

Returns Error::Io if the queue cannot be read.

async fn pop(&mut self) -> Result<Option<Vec<u8>>>

Removes and returns the oldest record in the queue.

Returns

Some(record) containing the oldest buffered bytes, or None if the queue is empty.

Errors

Returns Error::Io if the queue cannot be read.

async fn len(&self) -> Result<usize>

Returns the number of records currently buffered.

Returns

The count of records waiting to be drained.

Errors

Returns Error::Io if the queue length cannot be determined.

Provided Methods

async fn is_empty(&self) -> Result<bool>

Returns whether the queue currently holds no records.

The default implementation reports whether len is zero.

Returns

true if the queue is empty, false otherwise.

Errors

Returns Error::Io if the queue length cannot be determined.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors