includes/opentelemetry/common/key_value_iterable.h

Go to the documentation of this file.

// Copyright The OpenTelemetry Authors
// SPDX-License-Identifier: Apache-2.0
 
#pragma once
 
#include "opentelemetry/common/attribute_value.h"
#include "opentelemetry/nostd/function_ref.h"
#include "opentelemetry/nostd/string_view.h"
#include "opentelemetry/version.h"
 
OPENTELEMETRY_BEGIN_NAMESPACE
namespace common
{
class KeyValueIterable
{
public:
  virtual ~KeyValueIterable() = default;
 
  virtual bool ForEachKeyValue(nostd::function_ref<bool(nostd::string_view, common::AttributeValue)>
                                   callback) const noexcept = 0;
 
  virtual size_t size() const noexcept = 0;
};
 
class NoopKeyValueIterable : public KeyValueIterable
{
public:
  ~NoopKeyValueIterable() override = default;
 
  bool ForEachKeyValue(
      nostd::function_ref<bool(nostd::string_view, common::AttributeValue)> /*callback*/)
      const noexcept override
  {
    return true;
  }
 
  size_t size() const noexcept override { return 0; }
};
 
}  // namespace common
OPENTELEMETRY_END_NAMESPACE