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use std::time::Duration;
#[derive(Clone, Debug)]
#[derive(PartialEq, Eq)]
pub(crate) struct Config {
/// The time interval after which the next election will be initiated once the current lease has
/// expired.
pub(crate) election_timeout: Duration,
/// If this node has a smaller last-log-id than others, it will be less likely to be elected as
/// a leader. In this case, it is necessary to sleep for a longer period of time
/// `smaller_log_timeout` so that other nodes with a greater last-log-id have a chance to elect
/// themselves.
///
/// Note that this value should be greater than the `election_timeout` of every other node.
pub(crate) smaller_log_timeout: Duration,
/// The duration of an active leader's lease for a follower.
///
/// When a follower or learner perceives an active leader, such as by receiving an AppendEntries
/// message(including heartbeat), it should not grant the vote to another candidate during this
/// period. This prevents unnecessary elections when the leader is still active and helps
/// maintain cluster stability.
///
/// The leader uses this value to determine how long it can safely assume leadership without
/// sending heartbeats. A leader tracks the clock time acknowledged by followers to establish
/// a quorum-acknowledged time, ensuring no new leader can be elected before this lease expires.
pub(crate) leader_lease: Duration,
}
impl Default for Config {
fn default() -> Self {
Self {
election_timeout: Duration::from_millis(150),
smaller_log_timeout: Duration::from_millis(200),
leader_lease: Duration::from_millis(150),
}
}
}