cbdc::coordinator::state_machine Class Reference

Raft state machine for managing a replicated coordinator. More...

#include <state_machine.hpp>

Inheritance diagram for cbdc::coordinator::state_machine:

Collaboration diagram for cbdc::coordinator::state_machine:

Data Structures
struct	coordinator_state
	Used to store dtxs, which phase they are in and relevant data require for recovery. More...

Public Types
enum class	command : uint8_t {   prepare = 0 , commit = 1 , discard = 2 , done = 3 ,   get = 4 }
	Types of command the state machine can process. More...

Public Member Functions
	state_machine (std::shared_ptr< logging::log > logger)
	Constructor.
auto	commit (uint64_t log_idx, nuraft::buffer &data) -> nuraft::ptr< nuraft::buffer > override
	Commits a state machine command.
void	commit_config (nuraft::ulong log_idx, nuraft::ptr< nuraft::cluster_config > &) override
	Handler for the raft cluster configuration changes.
auto	apply_snapshot (nuraft::snapshot &) -> bool override
	Not implemented for coordinators.
auto	last_snapshot () -> nuraft::ptr< nuraft::snapshot > override
	Not implemented for coordinators.
auto	last_commit_index () -> uint64_t override
	Returns the index of the last-committed command.
void	create_snapshot (nuraft::snapshot &, nuraft::async_result< bool >::handler_type &when_done) override
	Not implemented for coordinators.

Detailed Description

Raft state machine for managing a replicated coordinator.

Contains a coordinator_state and the last-committed index. Accepts requests to manage and query distributed transactions.

Definition at line 21 of file uhs/twophase/coordinator/state_machine.hpp.

Member Enumeration Documentation

command

enum class cbdc::coordinator::state_machine::command : uint8_t

strong

Types of command the state machine can process.

Enumerator
prepare	Stores a dtx in the prepare phase.
commit	Moves a dtx from prepare to commit.
discard	Moves a dtx from commit to discard.
done	Clears the dtx from the coordinator state.
get	Retrieves all active dtxs.

Definition at line 30 of file uhs/twophase/coordinator/state_machine.hpp.

Constructor & Destructor Documentation

state_machine()

cbdc::coordinator::state_machine::state_machine ( std::shared_ptr< logging::log > logger )

explicit

Constructor.

Constructs a new coordinator state machine.

Parameters

logger

pointer to logger instance.

Definition at line 122 of file uhs/twophase/coordinator/state_machine.cpp.

Member Function Documentation

apply_snapshot()

auto cbdc::coordinator::state_machine::apply_snapshot ( nuraft::snapshot & ) -> bool

override

Not implemented for coordinators.

Returns

false (unconditionally).

Definition at line 101 of file uhs/twophase/coordinator/state_machine.cpp.

commit()

auto cbdc::coordinator::state_machine::commit ( uint64_t log_idx, nuraft::buffer & data ) -> nuraft::ptr<nuraft::buffer>

override

Commits a state machine command.

Parameters

log_idx	index of raft entry.
data	the buffer containing the command to commit.

Returns

pointer to a buffer with the serialized execution result or nullptr.

Definition at line 14 of file uhs/twophase/coordinator/state_machine.cpp.

References cbdc::serialized_size(), and cbdc::to_string().

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commit_config()

void cbdc::coordinator::state_machine::commit_config ( nuraft::ulong log_idx, nuraft::ptr< nuraft::cluster_config > &  )

override

Handler for the raft cluster configuration changes.

Parameters

log_idx

Raft log number of the configuration change.

Definition at line 94 of file uhs/twophase/coordinator/state_machine.cpp.

create_snapshot()

void cbdc::coordinator::state_machine::create_snapshot ( nuraft::snapshot & , nuraft::async_result< bool >::handler_type & when_done )

override

Not implemented for coordinators.

Definition at line 114 of file uhs/twophase/coordinator/state_machine.cpp.

last_commit_index()

auto cbdc::coordinator::state_machine::last_commit_index ( ) -> uint64_t

override

Returns the index of the last-committed command.

Definition at line 110 of file uhs/twophase/coordinator/state_machine.cpp.

last_snapshot()

auto cbdc::coordinator::state_machine::last_snapshot ( ) -> nuraft::ptr<nuraft::snapshot>

override

Not implemented for coordinators.

Returns

nullptr (unconditionally).

Definition at line 106 of file uhs/twophase/coordinator/state_machine.cpp.

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The documentation for this class was generated from the following files:

• uhs/twophase/coordinator/state_machine.hpp
• uhs/twophase/coordinator/state_machine.cpp