Enum Notification 

pub enum Notification {
    SwitchingToLive,
    ReorgDetected {
        common_ancestor: u64,
    },
    NoPastLogsFound,
}

Notifications emitted by the scanner to signal state changes or important events.

Variants

SwitchingToLive

Emitted when transitioning from the latest events phase to live streaming mode in sync scanners.

ReorgDetected

When a reorg occurs, the scanner adjusts its position to re-stream events from the canonical chain state. The specific behavior depends on the scanning mode (see individual scanner mode documentation for details).

Redundant Notifications

Due to the asynchronous nature of block scanning and log fetching, you may occasionally receive this notification even after the reorg has already been accounted for. This happens when:

1. BlockRangeScanner validates and emits a block range
2. A reorg occurs on the chain
3. EventScanner fetches logs for that range, but the RPC provider returns logs from the post-reorg chain state (the provider’s view has already updated)
4. BlockRangeScanner detects the reorg on its next check and emits Notification::ReorgDetected with a new range starting from the first reorged block
5. EventScanner re-fetches logs for this range, which may return duplicate logs already delivered in step 3 (the new range might also extend beyond the original range)

How to handle: This is a benign race condition. Your application should be designed to handle duplicate logs idempotently (e.g., using transaction hashes or log indices as deduplication keys). Depending on your application semantics, you may also treat this notification as a signal to roll back application state derived from blocks after the reported common ancestor.

Fields

common_ancestor: u64

The block number of the last block that is still valid on the canonical chain.

NoPastLogsFound

Emitted during the latest events phase when no matching logs are found in the scanned range.

Trait Implementations

impl Clone for Notification

fn clone(&self) -> Notification

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Notification

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

Formats the value using the given formatter.

impl<T: Clone> From<Notification> for ScannerMessage<T>

fn from(value: Notification) -> Self

Converts to this type from the input type.

impl<T: Clone> PartialEq<Notification> for ScannerMessage<T>

fn eq(&self, other: &Notification) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialEq for Notification

fn eq(&self, other: &Notification) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for Notification

impl StructuralPartialEq for Notification