polardbxengine/include/mysql/components/services/group_replication_message_s...

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/* Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License, version 2.0,
as published by the Free Software Foundation.
This program is also distributed with certain software (including
but not limited to OpenSSL) that is licensed under separate terms,
as designated in a particular file or component or in included license
documentation. The authors of MySQL hereby grant you an additional
permission to link the program and your derivative works with the
separately licensed software that they have included with MySQL.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License, version 2.0, for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
#ifndef GROUP_REPLICATION_MESSAGE_SERVICE_H
#define GROUP_REPLICATION_MESSAGE_SERVICE_H
#include <mysql/components/service.h>
#include <stddef.h>
/**
@ingroup group_components_services_inventory
A service that sends content agnostic messages from a member to the group.
This only works if the component is on a server with group replication
running and the member state is ONLINE. If server isn't ONLINE message won't
be deliver.
After message sent to all members of the group, all components that have
registered group_replication_message_service_recv service will be notified.
@code
SERVICE_TYPE(registry) *plugin_registry = mysql_plugin_registry_acquire();
my_service<SERVICE_TYPE(group_replication_message_service_send)> svc(
"group_replication_message_service_send", plugin_registry);
if (svc.is_valid()) {
bool error = svc->send("tag", "payload", sizeof("payload"));
}
@endcode
*/
BEGIN_SERVICE_DEFINITION(group_replication_message_service_send)
/**
This function SHALL be called whenever the caller wants to
send an agnostic messages to the group replication stream.
@param[in] tag tag identifies message
@param[in] payload data to be deliver
@param[in] payload_length size of data
@return false success, true on failure. Failure can happen if Group
Replication status isn't ONLINE or RECOVERING or a communication failure
occurs.
*/
DECLARE_BOOL_METHOD(send, (const char *tag, const unsigned char *payload,
const size_t payload_length));
END_SERVICE_DEFINITION(group_replication_message_service_send)
/**
A service that gets called whenever an agnostic message
from the group replication stream is to be delivered by
the group replication receiver thread.
The implementation MUST NOT block the caller.
This only works if the component is on a server with group replication
running and the member state is ONLINE. If server isn't ONLINE message won't
be notified about messages received.
@code
DEFINE_BOOL_METHOD(recv, (const char *tag, const unsigned char *data,
size_t data_length)) {
// If tag is of interest do something with data
return false;
}
BEGIN_SERVICE_IMPLEMENTATION(listener_example,
group_replication_message_service_recv)
recv, END_SERVICE_IMPLEMENTATION();
bool register_listener() {
SERVICE_TYPE(registry) *plugin_registry = mysql_plugin_registry_acquire();
my_service<SERVICE_TYPE(registry_registration)> reg("registry_registration",
plugin_registry);
using group_replication_message_service_recv_t =
SERVICE_TYPE_NO_CONST(group_replication_message_service_recv);
bool result = reg->register_service(
"group_replication_message_service_recv.listener_example",
reinterpret_cast<my_h_service>(
const_cast<group_replication_message_service_recv_t *>(
&SERVICE_IMPLEMENTATION(
listener_example,
group_replication_message_service_recv))));
@endcode
*/
BEGIN_SERVICE_DEFINITION(group_replication_message_service_recv)
/**
This function of every service implementation SHALL be called by group
replication whenever the group replication receive a service message sent to
the group.
@param[out] tag tag identifies message
@param[out] payload data to be deliver
@param[out] payload_length size of data
@return false success, true on failure.
*/
DECLARE_BOOL_METHOD(recv, (const char *tag, const unsigned char *payload,
const size_t payload_length));
END_SERVICE_DEFINITION(group_replication_message_service_recv)
#endif /* GROUP_REPLICATION_MESSAGE_SERVICE_H */