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WatchReader

laser_sdk::watch

Struct WatchReader 

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pub struct WatchReader { /* private fields */ }
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A resumable change-feed reader. Each poll drains the records that landed since the last one. Persist offsets and seed a fresh reader to resume across restarts, exactly like any Cursor.

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impl WatchReader

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pub fn from_offsets(self, offsets: Vec<u64>) -> Self

Resume from a previous reader’s offsets.

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pub async fn poll(&mut self) -> Result<Vec<ChangeRecord>, LaserError>

Drain the change records that landed since the last poll, filtered to the watched index when one was set. A record that does not decode as a ChangeRecord is skipped: the changes topic defaults to laser_wire::topics::CHANGES_TOPIC but is overridable (Laser::with_changes_topic), and a misbehaving deployment publishing other traffic on it must not wedge the reader either way.

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pub fn offsets(&self) -> &[u64]

The per-partition offsets consumed so far, the resume state.

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pub fn stream(self) -> impl Stream<Item = Result<ChangeRecord, LaserError>>

This reader as a Stream of change records, one at a time, draining what landed since the last read and ending once caught up (the same shape as the async reader in the Python binding). Drive it with futures::StreamExt.

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