Convenience wrapper to query a JSON configuration file. More...

#include <Config.hpp>

Public Types
using	KeyType = std::string

using	ArrayType = std::vector<Config>

using	WriteCursorType = std::pair<std::optional<std::reference_wrapper<boost::json::value>>, KeyType>

Public Member Functions
	Config (boost::json::value store={})
	Construct a new Config object.

	operator bool () const noexcept
	Checks whether underlying store is not null.

bool	contains (KeyType key) const
	Checks whether something exists under given key.

template<typename Result >
std::optional< Result >	maybeValue (KeyType key) const
	Interface for fetching values by key that returns std::optional.

template<typename Result >
Result	value (KeyType key) const
	Interface for fetching values by key.

template<typename Result >
Result	valueOr (KeyType key, Result fallback) const
	Interface for fetching values by key with fallback.

template<typename Result >
Result	valueOrThrow (KeyType key, std::string_view err) const
	Interface for fetching values by key with custom error handling.

std::optional< ArrayType >	maybeArray (KeyType key) const
	Interface for fetching an array by key that returns std::optional.

ArrayType	array (KeyType key) const
	Interface for fetching an array by key.

ArrayType	arrayOr (KeyType key, ArrayType fallback) const
	Interface for fetching an array by key with fallback.

ArrayType	arrayOrThrow (KeyType key, std::string_view err) const
	Interface for fetching an array by key with custom error handling.

Config	section (KeyType key) const
	Interface for fetching a sub section by key.

Config	sectionOr (KeyType key, boost::json::object fallback) const
	Interface for fetching a sub section by key with a fallback object.

template<typename Result >
std::optional< Result >	maybeValue () const
	Interface for reading the value directly referred to by the instance. Wraps as std::optional.

template<typename Result >
Result	value () const
	Interface for reading the value directly referred to by the instance.

template<typename Result >
Result	valueOr (Result fallback) const
	Interface for reading the value directly referred to by the instance with user-specified fallback.

template<typename Result >
Result	valueOrThrow (std::string_view err) const
	Interface for reading the value directly referred to by the instance with user-specified error message.

ArrayType	array () const
	Interface for reading the array directly referred to by the instance.

Static Public Member Functions
static std::chrono::milliseconds	toMilliseconds (float value)
	Method to convert a float seconds value to milliseconds.

Detailed Description

Convenience wrapper to query a JSON configuration file.

Any custom data type can be supported by implementing the right tag_invoke for boost::json::value_to.

Constructor & Destructor Documentation

◆ Config()

util::Config::Config ( boost::json::value store = {} )

explicit

Construct a new Config object.

Parameters

store boost::json::value that backs this instance

Member Function Documentation

◆ array() [1/2]

Config::ArrayType util::Config::array ( ) const

nodiscard

Interface for reading the array directly referred to by the instance.

See array(KeyType) const for how this works.

Returns: The array

◆ array() [2/2]

Config::ArrayType util::Config::array ( KeyType key ) const

nodiscard

Interface for fetching an array by key.

Will attempt to fetch an array under the desired key. If the array exists then it will be returned. If the array does not exist under the specified key an std::logic_error is thrown.

Parameters

key	The key to check

Returns: The array

Exceptions

std::logic_error Thrown if there is no array under the desired key or the key is of invalid format

◆ arrayOr()

Config::ArrayType util::Config::arrayOr	(	KeyType	key,
		ArrayType	fallback ) const

nodiscard

Interface for fetching an array by key with fallback.

Will attempt to fetch an array under the desired key. If the array exists then it will be returned. If the array does not exist or another type is stored under the desired key - user specified fallback is returned.

Parameters

key	The key to check
fallback	The fallback array

Returns: The array

Exceptions

std::logic_error Thrown if the key is of invalid format

◆ arrayOrThrow()

Config::ArrayType util::Config::arrayOrThrow	(	KeyType	key,
		std::string_view	err ) const

nodiscard

Interface for fetching an array by key with custom error handling.

Will attempt to fetch an array under the desired key. If the array exists then it will be returned. If the array does not exist or another type is stored under the desired key - std::runtime_error is thrown with the user specified error message.

Parameters

key	The key to check
err	The custom error message

Returns: The array

Exceptions

std::runtime_error Thrown if there is no array under the desired key

◆ contains()

bool util::Config::contains ( KeyType key ) const

nodiscard

Checks whether something exists under given key.

Parameters

key	The key to check

Returns: true If something exists under key; false If nothing exists under key

Exceptions

std::logic_error If the key is of invalid format

◆ maybeArray()

std::optional< Config::ArrayType > util::Config::maybeArray ( KeyType key ) const

nodiscard

Interface for fetching an array by key that returns std::optional.

Will attempt to fetch an array under the desired key. If the array exists then it will be returned wrapped in an optional. If the array does not exist under the specified key - std::nullopt is returned.

Parameters

key	The key to check

Returns: Optional array

Exceptions

std::logic_error Thrown if the key is of invalid format

◆ maybeValue() [1/2]

template<typename Result >

std::optional< Result > util::Config::maybeValue ( ) const

inlinenodiscard

Interface for reading the value directly referred to by the instance. Wraps as std::optional.

See maybeValue(KeyType) const for how this works.

Returns: Optional value

◆ maybeValue() [2/2]

template<typename Result >

std::optional< Result > util::Config::maybeValue ( KeyType key ) const

inlinenodiscard

Interface for fetching values by key that returns std::optional.

Will attempt to fetch the value under the desired key. If the value exists and can be represented by the desired type Result then it will be returned wrapped in an optional. If the value exists but the conversion to Result is not possible - a runtime_error will be thrown. If the value does not exist under the specified key - std::nullopt is returned.

Template Parameters

Result The desired return type

Parameters

key	The key to check

Returns: Optional value of desired type

Exceptions

std::logic_error Thrown if conversion to Result is not possible or key is of invalid format

◆ operator bool()

util::Config::operator bool ( ) const

noexcept

Checks whether underlying store is not null.

Returns: true If the store is null; false If the store is not null

◆ section()

Config util::Config::section ( KeyType key ) const

nodiscard

Interface for fetching a sub section by key.

Will attempt to fetch an entire section under the desired key and return it as a Config instance. If the section does not exist or another type is stored under the desired key - std::logic_error is thrown.

Parameters

key	The key to check

Returns: Section represented as a separate instance of Config

Exceptions

std::logic_error Thrown if there is no section under the desired key or the key is of invalid format

◆ sectionOr()

Config util::Config::sectionOr	(	KeyType	key,
		boost::json::object	fallback ) const

nodiscard

Interface for fetching a sub section by key with a fallback object.

Will attempt to fetch an entire section under the desired key and return it as a Config instance. If the section does not exist or another type is stored under the desired key - fallback object is used instead.

Parameters

key	The key to check
fallback	The fallback object

Returns: Section represented as a separate instance of Config

◆ toMilliseconds()

std::chrono::milliseconds util::Config::toMilliseconds ( float value )

static

Method to convert a float seconds value to milliseconds.

Parameters

value The value to convert

Returns: The value in milliseconds

◆ value() [1/2]

template<typename Result >

Result util::Config::value ( ) const

inlinenodiscard

Interface for reading the value directly referred to by the instance.

See value(KeyType) const for how this works.

Returns: The value

◆ value() [2/2]

template<typename Result >

Result util::Config::value ( KeyType key ) const

inlinenodiscard

Interface for fetching values by key.

Will attempt to fetch the value under the desired key. If the value exists and can be represented by the desired type Result then it will be returned. If the value exists but the conversion to Result is not possible OR the value does not exist - a logic_error will be thrown.

Template Parameters

Result The desired return type

Parameters

key	The key to check

Returns: Value of desired type

Exceptions

std::logic_error Thrown if conversion to Result is not possible, value does not exist under specified key path or the key is of invalid format

◆ valueOr() [1/2]

template<typename Result >

Result util::Config::valueOr	(	KeyType	key,
		Result	fallback ) const

inlinenodiscard

Interface for fetching values by key with fallback.

Will attempt to fetch the value under the desired key. If the value exists and can be represented by the desired type Result then it will be returned. If the value exists but the conversion to Result is not possible - a logic_error will be thrown. If the value does not exist under the specified key - user specified fallback is returned.

Template Parameters

Result The desired return type

Parameters

key	The key to check
fallback	The fallback value

Returns: Value of desired type

Exceptions

std::logic_error Thrown if conversion to Result is not possible or the key is of invalid format

◆ valueOr() [2/2]

template<typename Result >

Result util::Config::valueOr ( Result fallback ) const

inlinenodiscard

Interface for reading the value directly referred to by the instance with user-specified fallback.

See valueOr(KeyType, Result) const for how this works.

Parameters

fallback The fallback value

Returns: The value

◆ valueOrThrow() [1/2]

template<typename Result >

Result util::Config::valueOrThrow	(	KeyType	key,
		std::string_view	err ) const

inlinenodiscard

Interface for fetching values by key with custom error handling.

Will attempt to fetch the value under the desired key. If the value exists and can be represented by the desired type Result then it will be returned. If the value exists but the conversion to Result is not possible OR the value does not exist - a runtime_error will be thrown with the user specified message.

Template Parameters

Result The desired return type

Parameters

key	The key to check
err	The custom error message

Returns: Value of desired type

Exceptions

std::runtime_error Thrown if conversion to Result is not possible or value does not exist under key

◆ valueOrThrow() [2/2]

template<typename Result >

Result util::Config::valueOrThrow ( std::string_view err ) const

inlinenodiscard

Interface for reading the value directly referred to by the instance with user-specified error message.

See valueOrThrow(KeyType, std::string_view) const for how this works.

Parameters

err	The custom error message

Returns: The value

The documentation for this class was generated from the following files:

/__w/clio/clio/src/util/config/Config.hpp
/__w/clio/clio/src/util/config/Config.cpp

Public Types

Public Member Functions

Static Public Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ Config()

Member Function Documentation

◆ array() [1/2]

◆ array() [2/2]

◆ arrayOr()

◆ arrayOrThrow()

◆ contains()

◆ maybeArray()

◆ maybeValue() [1/2]

◆ maybeValue() [2/2]

◆ operator bool()

◆ section()

◆ sectionOr()

◆ toMilliseconds()

◆ value() [1/2]

◆ value() [2/2]

◆ valueOr() [1/2]

◆ valueOr() [2/2]

◆ valueOrThrow() [1/2]

◆ valueOrThrow() [2/2]