ai.eloquent.raft

Class RaftStateMachine

java.lang.Object

ai.eloquent.raft.RaftStateMachine

Direct Known Subclasses:

KeyValueStateMachine

public abstract class RaftStateMachine
extends java.lang.Object

This is the interface that any state machine needs to implement in order to be used with Theseus.

Constructor Summary

Constructors

Constructor and Description
RaftStateMachine()

Method Summary

Modifier and Type	Method and Description
protected abstract void	applyTransition(byte[] transition, long now, java.util.concurrent.ExecutorService pool) The custom implementation of applying a transition
java.lang.String	debugTransition(byte[] transition) This is used for debugging log entries.
java.util.Set<java.lang.String>	getHospice() Get the current hospice.
void	overwriteWithSerialized(byte[] serialized, long now, java.util.concurrent.ExecutorService pool) This overwrites the current state of the state machine with a serialized proto.
protected abstract void	overwriteWithSerializedImpl(byte[] serialized, long now, java.util.concurrent.ExecutorService pool) This overwrites the current state of the state machine with a serialized proto.
java.util.Set<java.lang.String>	owners() The set of nodes that own anything in the state machine.
byte[]	serialize() This serializes the state machine's current state into a proto that can be read from overwriteWithSerialized().
protected abstract com.google.protobuf.ByteString	serializeImpl() This serializes the state machine's current state into a proto that can be read from overwriteWithSerialized().

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

RaftStateMachine

public RaftStateMachine()

Method Detail

getHospice

public final java.util.Set<java.lang.String> getHospice()

Get the current hospice. This is a copy of the hospice, which means it is safe to mutate.

serializeImpl

protected abstract com.google.protobuf.ByteString serializeImpl()

This serializes the state machine's current state into a proto that can be read from overwriteWithSerialized().

Returns:

a proto of this state machine

serialize

public final byte[] serialize()

This serializes the state machine's current state into a proto that can be read from overwriteWithSerialized().

Returns:

a proto of this state machine

overwriteWithSerializedImpl

protected abstract void overwriteWithSerializedImpl(byte[] serialized,
                                                    long now,
                                                    java.util.concurrent.ExecutorService pool)

This overwrites the current state of the state machine with a serialized proto. All the current state of the state machine is overwritten, and the new state is substituted in its place.

Parameters:

serialized - the state machine to overwrite this one with, in serialized form

now - the current time, in epoch millis.

pool - an executor pool to run lock future commits on.

overwriteWithSerialized

public final void overwriteWithSerialized(byte[] serialized,
                                          long now,
                                          java.util.concurrent.ExecutorService pool)

This overwrites the current state of the state machine with a serialized proto. All the current state of the state machine is overwritten, and the new state is substituted in its place.

Parameters:

serialized - the state machine to overwrite this one with, in serialized form

now - the current time, in epoch millis.

pool - an executor pool to run lock future commits on.

applyTransition

protected abstract void applyTransition(byte[] transition,
                                        long now,
                                        java.util.concurrent.ExecutorService pool)

The custom implementation of applying a transition

debugTransition

public java.lang.String debugTransition(byte[] transition)

This is used for debugging log entries. Mostly ignored, but very useful for debugging fuzz tests that are failing.

Parameters:

transition - the transition to debug

Returns:

a rendered string version of the transition

owners

public java.util.Set<java.lang.String> owners()

The set of nodes that own anything in the state machine. This is an optional override, only for state machines that have a notion of ownership.