Packages
ra
0.9.2
3.1.9
3.1.8
3.1.7
3.1.6
3.1.5
3.1.4
3.1.3
3.1.2
3.1.1
3.1.0
3.0.2
3.0.1
3.0.0
3.0.0-beta.1
2.17.3
2.17.2
2.17.1
2.17.0
2.16.13
2.16.12
2.16.11
2.16.10
2.16.9
2.16.8
2.16.7
2.16.6
2.16.5
2.16.4
2.16.3
2.16.2
2.16.1
2.16.0
2.16.0-pre.12
2.16.0-pre.11
2.16.0-pre.10
2.16.0-pre.9
2.16.0-pre.8
2.16.0-pre.7
2.16.0-pre.6
2.16.0-pre.5
2.16.0-pre.4
2.16.0-pre.3
2.16.0-pre.2
2.16.0-pre.1
2.15.4
2.15.3
2.15.2
2.15.1
2.15.0
2.14.0
2.13.6
2.13.5
2.13.4
2.13.3
2.13.2
2.13.1
2.13.0
2.13.0-pre.1
2.12.0
2.11.0
2.11.0-pre.1
2.10.2-pre.2
2.10.2-pre.1
2.10.1
2.10.0
2.10.0-pre.3
2.10.0-pre.2
2.10.0-pre.1
2.9.10-pre.1
2.9.1
2.9.1-pre.2
2.9.1-pre.1
2.9.0
2.8.0
retired
2.7.3
2.7.2
2.7.1
2.7.0
2.7.0-pre.3
2.7.0-pre.2
2.7.0-pre.1
2.6.3
2.6.2
2.6.1
2.6.0-pre.1
2.5.1
2.5.1-pre.1
2.5.0
2.4.9
2.4.8
2.4.7
2.4.6
2.4.5
2.4.4
2.4.3
2.4.2
retired
2.4.1
2.4.0
2.3.0
2.2.0
2.1.0
2.0.13
2.0.12
2.0.11
2.0.10
2.0.9
2.0.8
2.0.7
2.0.6
2.0.5
2.0.4
2.0.3
2.0.2
2.0.1
2.0.0
1.1.9
1.1.8
1.1.7
1.1.6
1.1.5
1.1.4
1.1.3
1.1.2
1.1.1
1.1.0
1.0.8
1.0.7
1.0.6
1.0.5
1.0.4
1.0.3
1.0.2
1.0.1
1.0.0
0.9.6
0.9.5
0.9.4
0.9.2
0.3.3
retired
0.3.2
retired
0.3.1
retired
Raft library
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include/ra.hrl
-type maybe(T) :: undefined | T.
%%
%% Most of the records here are covered on Figure 2
%% in the Raft paper (extended version):
%% https://raft.github.io/raft.pdf.
%%
%% taken from gen_statem as this type isn't exported for some reason.
-type from() ::
{To :: pid(), Tag :: term()}.
%% Sections 5.1 in the paper.
-type ra_index() :: non_neg_integer().
%% Section 5.3.
-type ra_term() :: non_neg_integer().
%% tuple form of index and term
-type ra_idxterm() :: {ra_index(), ra_term()}.
%% Sections 5.1-5.3.
%% a friendly name for the cluster
-type ra_cluster_name() :: binary() | string() | atom().
%% Uniquely identifies a ra server on a local erlang node
%% used for on disk resources and local name to pid mapping
-type ra_uid() :: binary().
%% Identifies a ra server in a ra cluster
%% NB: ra servers need to be registered as need to be reachable under the old
%% name after restarts. Pids won't do.
-type ra_server_id() :: atom() | {Name :: atom(), Node :: node()}.
-type ra_peer_state() :: #{next_index => non_neg_integer(),
match_index => non_neg_integer(),
% the commit index last sent
% used for evaluating pipeline status
commit_index_sent => non_neg_integer()}.
-type ra_cluster() :: #{ra_server_id() => ra_peer_state()}.
-type ra_cluster_servers() :: [ra_server_id()].
%% represent a unique entry in the ra log
-type log_entry() :: {ra_index(), ra_term(), term()}.
-define(RA_PROTO_VERSION, 1).
%% the protocol version should be incremented whenever extensions need to be
%% done to the core protocol records (below). It is only ever exchanged by the
%% pre_vote message so that servers can reject pre votes for servers running a
%% higher protocol version. This should be sufficient to disallow a server with
%% newer protocol version to become leader before it has a majority and thus
%% potentially exchange incompatible message types with servers running older
%% code.
%%
%% If fields need to be added to any of the below records it is suggested that
%% a new record is created (by appending _vPROTO_VERSION). The server still need
%% to be able to handle and reply to the older message types to ensure
%% availability.
%% Figure 2 in the paper
-record(append_entries_rpc,
{term :: ra_term(),
leader_id :: ra_server_id(),
leader_commit :: ra_index(),
prev_log_index :: non_neg_integer(),
prev_log_term :: ra_term(),
entries = [] :: [log_entry()]}).
-record(append_entries_reply,
{term :: ra_term(),
success :: boolean(),
% because we aren't doing true rpc we may have multiple append
% entries in flight we need to communicate what we are replying
% to
% because writes are fsynced asynchronously we need to indicate
% the last index seen as well as the last index persisted.
next_index :: ra_index(),
% the last index that has been fsynced to disk
last_index :: ra_index(),
last_term :: ra_term()}).
%% Section 5.2
-record(request_vote_rpc,
{term :: ra_term(),
candidate_id :: ra_server_id(),
last_log_index :: ra_index(),
last_log_term :: ra_index()}).
%% Section 4.2
-record(request_vote_result,
{term :: ra_term(),
vote_granted :: boolean()}).
%% pre-vote extension
-record(pre_vote_rpc,
{version = ?RA_PROTO_VERSION :: non_neg_integer(),
term :: ra_term(),
token :: reference(),
candidate_id :: ra_server_id(),
last_log_index :: ra_index(),
last_log_term :: ra_index()}).
-record(pre_vote_result,
{term :: ra_term(),
token :: reference(),
vote_granted :: boolean()}).
-record(install_snapshot_rpc,
{term :: ra_term(), % the leader's term
leader_id :: ra_server_id(),
% the snapshot replaces all previous entries incl this
last_index :: ra_index(),
% the term at the point of snapshot
last_term :: ra_term(),
last_config :: ra_cluster_servers(),
data :: term()
}).
-record(install_snapshot_result,
{term :: ra_term(),
% because we aren't doing true rpc we may have multiple append
% entries in flight we need to communicate what we are replying
% to
last_index :: ra_index(),
last_term :: ra_term()}).
%% WAL defaults
-define(WAL_MAX_SIZE_BYTES, 1024 * 1024 * 1024).
% primitive logging abstraction
-define(error, true).
-define(warn, true).
-define(info, true).
-ifdef(info).
-define(INFO(Fmt, Args), error_logger:info_msg(Fmt, Args)).
-else.
-define(INFO(_F, _A), ok).
-endif.
-ifdef(warn).
-define(WARN(Fmt, Args), error_logger:warning_msg(Fmt, Args)).
-else.
-define(WARN(_, _), ok).
-endif.
-ifdef(error).
-define(ERR(Fmt, Args), error_logger:error_msg(Fmt, Args)).
-else.
-define(ERR(_, _), ok).
-endif.
-define(DEFAULT_TIMEOUT, 5000).