Crate noxu_rep 

Internal component of the noxu database.

This crate is published only so the noxu umbrella crate can depend on it. Use noxu (noxu = "7") in applications; depend on this crate directly only if you are extending the engine internals. Its API may change without a major version bump.

Replication and high availability for Noxu DB.

master-replica replication with automatic elections, VLSN tracking, network restore, and subscription.

Architecture

The replication layer consists of:

• ReplicatedEnvironment – Entry point that wraps a standard Environment and adds replication capabilities. Rep.ReplicatedEnvironment`.
• Elections – Automatic master election using majority voting. Rep.elections`.
• VLSN Index – Maps version sequence numbers to log file positions.
• Feeder/Replica Stream – Master-to-replica log entry streaming. Port
• Network Transport – Pluggable channel-based communication. Rep.net`.
• Group Service – Replication group membership management.
• Consistency Policies – Configurable replica consistency guarantees.
• Master Transfer – Controlled transfer of master role.
• Network Restore – Full node restore from another replica.
• Subscription – External subscription to the replication stream.

Node States

A replication node transitions through the following states:

• Detached – Not associated with the group (handle closed).
• Unknown – Not in contact with the master, actively trying to establish contact or decide upon a master.
• Master – The unique master of the group; can read and write.
• Replica – Being updated by the master; read-only.

The state transitions visible to the application follow:

[ MASTER | REPLICA | UNKNOWN ]+ DETACHED

Example

use noxu_rep::{ReplicatedEnvironment, RepConfig, NodeType};

let config = RepConfig::builder("my_group", "node1", "localhost")
    .node_port(14_001)
    .node_type(NodeType::Electable)
    .build();
let rep_env = ReplicatedEnvironment::new(config).unwrap();

Re-exports

pub use auth::PeerAllowlist;

pub use commit_durability::CommitDurability;

pub use commit_durability::ReplicaAckPolicy;

pub use commit_token::CommitToken;

pub use consistency::ConsistencyPolicy;

pub use consistency::ConsistencyTracker;

pub use elections::phi_detector::PhiAccrualDetector;

pub use error::RepError;

pub use error::Result;

pub use master_transfer::MasterTransfer;

pub use master_transfer::MasterTransferConfig;

pub use master_transfer::TransferState;

pub use net::InMemoryEndpoint;

pub use net::InMemoryGroup;

pub use net::InMemoryTransport;

pub use network_restore::NetworkRestore;

pub use network_restore::NetworkRestoreConfig;

pub use network_restore::RestoreState;

pub use network_restore_server::NetworkRestoreServer;

pub use network_restore_server::RESTORE_SERVICE_NAME;

pub use node_state::NodeState;

pub use node_state::NodeStateMachine;

pub use node_type::NodeType;

pub use quorum_policy::QuorumPolicy;

pub use rep_config::RepConfig;

pub use rep_config::RepTransportKind;

pub use rep_group::RepGroup;

pub use rep_node::RepNode;

pub use rep_stats::RepStats;

pub use replicated_environment::ReplicatedEnvironment;

pub use replicated_environment::SyncupAction;

pub use state_change_listener::StateChangeEvent;

pub use state_change_listener::StateChangeListener;

pub use stream::reconnect::ReconnectConfig;

pub use stream::reconnect::ReconnectOutcome;

pub use stream::reconnect::catch_up_with_retry;

pub use subscription::Subscription;

pub use subscription::SubscriptionCallback;

pub use subscription::SubscriptionConfig;

pub use subscription::SubscriptionState;

pub use tls::TlsConfig;

pub use tls::TlsIdentity;

pub use tls::TrustedCerts;

Modules

ack_tracker

Acknowledgment tracking for replication commits.

auth

Peer authentication and authorisation for replication.

commit_durability

Commit durability settings for replication.

commit_token

Commit tokens for commit-point read consistency.

consistency

Consistency policies for replica reads.

elections

Election subsystem for Noxu DB replication.

error

Replication error types.

group_admin

Group-administration service: master transfer and group shutdown.

group_service

Group membership service for replication.

master_transfer

Master transfer support.

net

Network transport layer for Noxu DB replication.

network_restore

Network restore for copying database files from another node.

network_restore_server

Server-side network restore: stream log files to a requesting node.

node_state

Node state machine for replication nodes.

node_type

Replication node types.

protocol

Replication protocol messages.

quorum_policy

Quorum policy for Flexible Paxos (Howard 2019).

rep_config

Replication configuration.

rep_group

Replication group management.

rep_node

Replication node information.

rep_stats

Replication statistics.

replicated_environment

The main replicated environment API.

state_change_listener

State change notification for replication nodes.

stream

Replication stream subsystem.

subscription

Replication subscription for receiving replicated entries from a feeder.

test_harness

In-memory test harness for replication group testing.

tls

TLS configuration for Noxu DB replication channels.

vlsn

VLSN tracking subsystem.