core/consensus/src/lib.rs

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use message_bus::MessageBus;

pub trait Project<T> {
    type Consensus: Consensus;
    fn project(self, consensus: &Self::Consensus) -> T;
}

pub trait Consensus {
    type MessageBus: MessageBus;
    // I am wondering, whether we should create a dedicated trait for cloning, so it's explicit that we do ref counting.
    type RequestMessage: Project<Self::ReplicateMessage, Consensus = Self> + Clone;
    type ReplicateMessage: Project<Self::AckMessage, Consensus = Self> + Clone;
    type AckMessage;
    type Sequencer: Sequencer;

    fn pipeline_message(&self, message: Self::ReplicateMessage);
    fn verify_pipeline(&self);

    // TODO: Figure out how we can achieve that without exposing such methods in the Consensus trait.
    fn post_replicate_verify(&self, message: &Self::ReplicateMessage);

    fn is_follower(&self) -> bool;
    fn is_syncing(&self) -> bool;
}

mod impls;
pub use impls::*;

mod vsr_timeout;