khepri

%% This Source Code Form is subject to the terms of the Mozilla Public
%% License, v. 2.0. If a copy of the MPL was not distributed with this
%% file, You can obtain one at https://mozilla.org/MPL/2.0/.
%%
%% Copyright © 2021-2022 VMware, Inc. or its affiliates.  All rights reserved.
%%

-define(DEFAULT_RA_SYSTEM_NAME, khepri).
-define(DEFAULT_STORE_ID, khepri).
-define(IS_STORE_ID(StoreId), is_atom(StoreId)).

-define(INIT_DATA_VERSION, 1).
-define(INIT_CHILD_LIST_VERSION, 1).
-define(INIT_NODE_STAT, #{payload_version => ?INIT_DATA_VERSION,
                          child_list_version => ?INIT_CHILD_LIST_VERSION}).

-define(TX_STATE_KEY, khepri_tx_machine_state).
-define(TX_PROPS, khepri_tx_properties).

-define(NO_PAYLOAD, '$__NO_PAYLOAD__').
-record(p_data, {data :: khepri:data()}).
-record(p_sproc, {sproc :: khepri_fun:standalone_fun()}).

-define(IS_KHEPRI_PAYLOAD(Payload), (Payload =:= ?NO_PAYLOAD orelse
                                     is_record(Payload, p_data) orelse
                                     is_record(Payload, p_sproc))).

-define(IS_TIMEOUT(Timeout), (Timeout =:= infinity orelse
                              (is_integer(Timeout) andalso Timeout >= 0))).
-define(HAS_TIME_LEFT(Timeout), (Timeout =:= infinity orelse Timeout > 0)).

%% timer:sleep/1 time used as a retry interval when the local Ra server is
%% unaware of a leader exit.
-define(NOPROC_RETRY_INTERVAL, 200).

-record(evf_tree, {path :: khepri_path:native_pattern(),
                   props = #{} :: khepri_evf:tree_event_filter_props()}).
%-record(evf_process, {pid :: pid(),
%                      props = #{} :: #{on_reason => ets:match_pattern(),
%                                       priority => integer()}}).

-define(IS_KHEPRI_EVENT_FILTER(EventFilter),
        (is_record(EventFilter, evf_tree))).

%% Structure representing each node in the tree, including the root node.
%% TODO: Rename stat to something more correct?
-record(node, {stat = ?INIT_NODE_STAT :: khepri_machine:stat(),
               payload = ?NO_PAYLOAD :: khepri_payload:payload(),
               child_nodes = #{} :: #{khepri_path:component() := #node{}}}).

%% State machine commands.

-record(put, {path :: khepri_path:native_pattern(),
              payload = ?NO_PAYLOAD :: khepri_payload:payload(),
              extra = #{} :: #{keep_while =>
                               khepri_condition:native_keep_while()}}).

-record(delete, {path :: khepri_path:native_pattern()}).

-record(tx, {'fun' :: khepri_fun:standalone_fun()}).

-record(register_trigger, {id :: khepri:trigger_id(),
                           event_filter :: khepri_evf:event_filter(),
                           sproc :: khepri_path:native_path()}).

-record(ack_triggered, {triggered :: [khepri_machine:triggered()]}).

-record(triggered, {id :: khepri:trigger_id(),
                    %% TODO: Do we need a ref to distinguish multiple
                    %% instances of the same trigger?
                    event_filter :: khepri_evf:event_filter(),
                    sproc :: khepri_fun:standalone_fun(),
                    props = #{} :: map()}).