// Copyright 2021-2023 Bloomberg Finance L.P. // SPDX-License-Identifier: Apache-2.0 // // Licensed under the Apache License, Version 2.0 (the "License"); // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // // http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. // See the License for the specific language governing permissions and // limitations under the License. // bmqpi_hosthealthmonitor.h -*-C++-*- #ifndef INCLUDED_BMQPI_HOSTHEALTHMONITOR #define INCLUDED_BMQPI_HOSTHEALTHMONITOR //@PURPOSE: Provide an interface for monitoring the health of the host. // //@CLASSES: // bmqpi::HostHealthMonitor: Interface for a monitor of host health. // //@DESCRIPTION: // 'bmqpi::HostHealthMonitor' is a pure interface for a monitor of the health // of the host. BlazingMQ sessions can use such objects to conditionally // suspend queue activity while the host is marked unhealthy. // BMQ #include <bmqscm_version.h> #include <bmqt_hosthealthstate.h> // BDE #include <bsl_functional.h> #include <bdlmt_signaler.h> namespace BloombergLP { namespace bmqpi { // ======================= // class HostHealthMonitor // ======================= class HostHealthMonitor { // A pure interface for monitoring the health of the host. public: // TYPES typedef bsl::function<void(bmqt::HostHealthState::Enum)> HostHealthChangeFn; // Invoked as a response to the HostHealthMonitor detecting a change // in the state of the host health. public: // CREATORS virtual ~HostHealthMonitor(); // Destructor // MANIPULATORS virtual bdlmt::SignalerConnection observeHostHealth(const HostHealthChangeFn& cb) = 0; // Registers the specified `cb` to be invoked each time the health of // the host changes. // ACCESSORS virtual bmqt::HostHealthState::Enum hostState() const = 0; // Queries the current health of the host. }; } // close package namespace } // close enterprise namespace #endif