foundationdb/fdbclient/IKnobCollection.h

72 lines
2.7 KiB
C++

/*
* IKnobCollection.h
*
* This source file is part of the FoundationDB open source project
*
* Copyright 2013-2018 Apple Inc. and the FoundationDB project authors
*
* 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.
*/
#pragma once
#include <memory>
#include "fdbclient/ClientKnobs.h"
#include "fdbclient/ConfigKnobs.h"
#include "fdbclient/ServerKnobs.h"
#include "flow/Knobs.h"
/*
* Each IKnobCollection instantiation stores several Knobs objects, and when parsing or setting a knob,
* these Knobs objects will be traversed in order, until the requested knob name is found. The order of traversal is:
* - FlowKnobs
* - ClientKnobs
* - ServerKnobs
* - TestKnobs
*/
class IKnobCollection {
static std::unique_ptr<IKnobCollection> globalKnobCollection;
public:
virtual ~IKnobCollection() = default;
enum class Type {
CLIENT,
SERVER,
TEST,
};
static std::unique_ptr<IKnobCollection> create(Type, Randomize, IsSimulated);
virtual void initialize(Randomize randomize, IsSimulated isSimulated) = 0;
virtual void reset(Randomize randomize, IsSimulated isSimulated) = 0;
virtual FlowKnobs const& getFlowKnobs() const = 0;
virtual ClientKnobs const& getClientKnobs() const = 0;
virtual ServerKnobs const& getServerKnobs() const = 0;
virtual class TestKnobs const& getTestKnobs() const = 0;
virtual void clearTestKnobs() {}
virtual Optional<KnobValue> tryParseKnobValue(std::string const& knobName, std::string const& knobValue) const = 0;
KnobValue parseKnobValue(std::string const& knobName, std::string const& knobValue) const;
static KnobValue parseKnobValue(std::string const& knobName, std::string const& knobValue, Type);
// Result indicates whether or not knob was successfully set:
virtual bool trySetKnob(std::string const& knobName, KnobValueRef const& knobValue) = 0;
void setKnob(std::string const& knobName, KnobValueRef const& knobValue);
virtual bool isAtomic(std::string const& knobName) const = 0;
static void setGlobalKnobCollection(Type, Randomize, IsSimulated);
static IKnobCollection const& getGlobalKnobCollection();
static IKnobCollection& getMutableGlobalKnobCollection();
static ConfigMutationRef createSetMutation(Arena, KeyRef, ValueRef);
static ConfigMutationRef createClearMutation(Arena, KeyRef);
};