Function get_view_changes

atomic-repository/src/apply/queries.rs:24–46

Get all change hashes in a view. Returns the hashes in order from oldest (sequence 0) to newest. # Arguments `txn` - Read transaction `view` - The view to get changes from # Returns Ordered vector of (sequence, hash) pairs.

(txn: &T, view: &ViewState)

///
/// Ordered vector of (sequence, hash) pairs.
pub fn get_view_changes<T: ViewTxnT>(txn: &T, view: &ViewState) -> InsertResult<Vec<(u64, Hash)>> {
    let mut changes = Vec::new();

    let iter = txn
        .iter_changes(view, 0)
        .map_err(|e| InsertError::Database(e.to_string()))?;

    for result in iter {
        let (seq, node_id, _merkle) = result.map_err(|e| InsertError::Database(e.to_string()))?;

        // Get external hash
        let hash = txn
            .get_external(node_id)
            .map_err(|e| InsertError::Database(e.to_string()))?
            .ok_or_else(|| {
                InsertError::Internal(format!("Change {} has no external hash", node_id.0))
            })?;

        changes.push((seq, hash));
    }

    Ok(changes)
}

/// Get changes that are in the source view but not in the target view.
///