runtime_features.h

#pragma once

#include <cstdint>

#include "envoy/runtime/runtime.h"

#include "source/common/singleton/const_singleton.h"

#include "absl/container/flat_hash_map.h"
#include "absl/flags/commandlineflag.h"
#include "absl/flags/flag.h"
#include "absl/strings/string_view.h"

namespace Envoy {
namespace Runtime {

bool hasRuntimePrefix(absl::string_view feature);
bool isRuntimeFeature(absl::string_view feature);

// Returns true if the feature is one of the legacy runtime features that uses the
// `envoy.reloadable_features` prefix but is not implemented like all other runtime
// feature flags.
bool isLegacyRuntimeFeature(absl::string_view feature);

bool runtimeFeatureEnabled(absl::string_view feature);
uint64_t getInteger(absl::string_view feature, uint64_t default_value);

void markRuntimeInitialized();
bool isRuntimeInitialized();

void maybeSetRuntimeGuard(absl::string_view name, bool value);

void maybeSetDeprecatedInts(absl::string_view name, uint32_t value);
constexpr absl::string_view upstream_http_filters_with_tcp_proxy =
    "envoy.restart_features.upstream_http_filters_with_tcp_proxy";

// This is a singleton class to map Envoy style flag names to absl flags
class RuntimeFeatures {
public:
  RuntimeFeatures();

  // Get the command line flag corresponding to the Envoy style feature name, or
  // nullptr if it is not a registered flag.
  absl::CommandLineFlag* getFlag(absl::string_view feature) const;

private:
  absl::flat_hash_map<std::string, absl::CommandLineFlag*> all_features_;
};

using RuntimeFeaturesDefaults = ConstSingleton<RuntimeFeatures>;

} // namespace Runtime
} // namespace Envoy