2026-07-11 15:55:22 +08:00

115 lines
2.7 KiB
C++

//
// Collector.h
//
// Library: Prometheus
// Package: Core
// Module: Collector
//
// Definition of the Collector class.
//
// Copyright (c) 2022, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// SPDX-License-Identifier: BSL-1.0
//
#ifndef Prometheus_Collector_INCLUDED
#define Prometheus_Collector_INCLUDED
#include "Poco/Prometheus/Prometheus.h"
#include "Poco/Prometheus/Registry.h"
namespace Poco {
namespace Prometheus {
class Exporter;
class Registry;
class Prometheus_API Collector
/// This is the base class for all metrics, such as
/// Counter, Gauge and Histogram.
///
/// Collector objects automatically register themselves
/// with the default Registry (unless a nullptr is passed to the
/// constructor's pRegistry parameter), but do not automatically
/// unregister. This brings the danger of dangling pointers if
/// Collector instances are destroyed without being explicitly
/// unregistered first. In most practical cases this is not an
/// issue as Collector instances will be alive for the entire
/// run time of the process. However, it can be an issue if
/// Collector instances are created and destroyed dynamically
/// during the run time of the process.
{
public:
const std::string& name() const;
/// Returns the metric's name.
virtual void exportTo(Exporter& exporter) const = 0;
/// Writes the given Metric to the Exporter.
virtual ~Collector() = default;
/// Destroys the Collector.
protected:
Collector(const std::string& name);
/// Creates a Collector with the given name
/// and registers it with the default Registry.
///
/// The name must be a valid metric name and match the regular
/// expression [a-zA-Z_:][a-zA-Z0-9_:]*.
Collector(const std::string& name, Registry* pRegistry);
/// Creates a Collector with the given name
/// and registers it with the given Registry (if not nullptr).
///
/// The name must be a valid metric name and match the regular
/// expression [a-zA-Z_:][a-zA-Z0-9_:]*.
static const std::string& validateName(const std::string& name);
private:
const std::string _name;
Collector() = delete;
Collector(const Collector&) = delete;
Collector(Collector&&) = delete;
Collector& operator = (const Collector&) = delete;
Collector& operator = (Collector&&) = delete;
};
//
// inlines
//
inline Collector::Collector(const std::string& name):
_name(validateName(name))
{
Registry::defaultRegistry().registerCollector(this);
}
inline Collector::Collector(const std::string& name, Registry* pRegistry):
_name(validateName(name))
{
if (pRegistry) pRegistry->registerCollector(this);
}
inline const std::string& Collector::name() const
{
return _name;
}
} } // namespace Poco::Prometheus
#endif // Prometheus_Collector_INCLUDED