proto_structs Namespace Reference

Detailed Description

Top namespace for the proto-structs library.

Namespaces
namespace	traits
	Namespace contains types for obtaining meta information (traits, concepts, etc.)

Classes
class	Any
	Wrapper for google.protobuf.Any which provides interface to access stored message as compatible struct. More...
class	AnyPackError
	Failed to pack struct's compatible message to proto_structs::Any underlying storage. More...
class	AnyUnpackError
	Failed to unpack struct's compatible message from proto_structs::Any underlying storage. More...
class	ConversionError
	Conversion error Exception is thrown if protobuf message field can't be converted to/from struct field. More...
class	Error
	Library basic exception type All other proto-structs exceptions are derived from this type. More...
class	Oneof
	Wrapper for oneof protobuf message fields. More...
class	OneofAccessError
	Trying to access unset proto_structs::Oneof field. More...
struct	To
	An ADL helper which allows locating functions to read structs from protobuf messages inside struct-specific namespaces. More...

Typedefs
template<std::size_t Index, typename T>
using	OneofAlternativeTrait = impl::OneofAlternativeTrait<Index, std::remove_cv_t<T>>
	Provides information about proto_structs::Oneof field type at position Index
template<std::size_t Index, typename T>
using	OneofAlternativeType = OneofAlternativeTrait<Index, T>::Type
template<typename Key, typename Value>
using	HashMap
	The hash map container used in userver proto structs by default.

Functions
template<traits::ProtoMessage TMessage, traits::ProtoStruct TStruct>
void	MessageToStruct (const TMessage &msg, TStruct &obj)
	Converts protobuf message msg to struct obj.
template<traits::ProtoStruct TStruct, traits::ProtoMessage TMessage>
TStruct	MessageToStruct (const TMessage &msg)
	Converts protobuf message msg to specified structure type.
template<typename TStruct, traits::ProtoMessage TMessage> requires traits::ProtoStruct<std::remove_cvref_t<TStruct>>
void	StructToMessage (TStruct &&obj, TMessage &msg)
	Converts struct instance obj to protobuf message msg.
template<traits::ProtoMessage TMessage, typename TStruct> requires traits::ProtoStruct<std::remove_cvref_t<TStruct>>
TMessage	StructToMessage (TStruct &&obj)
	Converts struct instance obj to protobuf message msg of the specified type.
template<typename TStruct> requires traits::CompatibleStruct<std::remove_cvref_t<TStruct>>
traits::CompatibleMessageType< std::remove_cvref_t< TStruct > >	StructToMessage (TStruct &&obj)
	Converts struct instance obj to it's compatible protobuf message.

Variables
constexpr std::size_t	kOneofNpos = -1
	Special index value used to indicate oneof without any field set.

Typedef Documentation

HashMap

template<typename Key, typename Value>

using proto_structs::HashMap

Initial value:

 std::unordered_map<
    Key,
    Value,
    std::conditional_t<std::is_convertible_v<Key, std::string_view>, utils::StrCaseHash, std::hash<Key>>>

The hash map container used in userver proto structs by default.

Currently implemented as just std::unordered_map. Please don't assume it! For example:

• Don't pass the field to functions as std::unordered_map, use proto_structs::HashMap instead;
• Don't use node and bucket APIs of std::unordered_map with these fields.

Definition at line 22 of file hash_map.hpp.

OneofAlternativeTrait

template<std::size_t Index, typename T>

using proto_structs::OneofAlternativeTrait = impl::OneofAlternativeTrait<Index, std::remove_cv_t<T>>

Provides information about proto_structs::Oneof field type at position Index

Definition at line 58 of file oneof.hpp.

OneofAlternativeType

template<std::size_t Index, typename T>

using proto_structs::OneofAlternativeType = OneofAlternativeTrait<Index, T>::Type

Definition at line 61 of file oneof.hpp.

Function Documentation

MessageToStruct() [1/2]

template<traits::ProtoStruct TStruct, traits::ProtoMessage TMessage>

TStruct proto_structs::MessageToStruct ( const TMessage & msg )

nodiscard

Converts protobuf message msg to specified structure type.

Template Parameters

TStruct	struct type
TMessage	protobuf message type

Exceptions

ConversionError

if conversion failed

Function calls ReadStruct(obj, msg) under the hood which should be foundable by argument-dependent lookup.

Definition at line 39 of file convert.hpp.

MessageToStruct() [2/2]

template<traits::ProtoMessage TMessage, traits::ProtoStruct TStruct>

void proto_structs::MessageToStruct	(	const TMessage &	msg,
		TStruct &	obj )

Converts protobuf message msg to struct obj.

Template Parameters

TMessage	protobuf message type
TStruct	struct type

Exceptions

ConversionError

if conversion failed (in that case obj is not modified)

Note

If function throws an exception, obj is not modified

Function calls ReadStruct(obj, msg) under the hood which should be foundable by argument-dependent lookup.

Definition at line 26 of file convert.hpp.

StructToMessage() [1/3]

template<traits::ProtoMessage TMessage, typename TStruct>
requires traits::ProtoStruct<std::remove_cvref_t<TStruct>>

TMessage proto_structs::StructToMessage ( TStruct && obj )

nodiscard

Converts struct instance obj to protobuf message msg of the specified type.

Template Parameters

TStruct	struct type
TMessage	protobuf message type

Exceptions

ConversionError

if conversion failed

Function calls WriteStruct(std::forward<TStruct>(obj), msg) under the hood which should be foundable by argument-dependent lookup.

Definition at line 70 of file convert.hpp.

StructToMessage() [2/3]

template<typename TStruct>
requires traits::CompatibleStruct<std::remove_cvref_t<TStruct>>

traits::CompatibleMessageType< std::remove_cvref_t< TStruct > > proto_structs::StructToMessage ( TStruct && obj )

nodiscard

Converts struct instance obj to it's compatible protobuf message.

Template Parameters

TStruct

struct type

Exceptions

ConversionError

if conversion failed

Compatability information should be provided for TStruct with proto_structs::compatible_message, otherwise compilation will fail.

Function calls WriteStruct(std::forward<TStruct>(obj), msg) under the hood which should be foundable by argument-dependent lookup.

Definition at line 87 of file convert.hpp.

StructToMessage() [3/3]

template<typename TStruct, traits::ProtoMessage TMessage>
requires traits::ProtoStruct<std::remove_cvref_t<TStruct>>

void proto_structs::StructToMessage	(	TStruct &&	obj,
		TMessage &	msg )

Converts struct instance obj to protobuf message msg.

Template Parameters

TStruct	struct type
TMessage	protobuf message type

Exceptions

ConversionError

if conversion failed (in that case msg is not modified)

Warning

If function throws an exception, msg is left in a valid but unspecified state

Function calls WriteStruct(std::forward<TStruct>(obj), msg) under the hood which should be foundable by argument-dependent lookup.

Definition at line 55 of file convert.hpp.

Variable Documentation

kOneofNpos

std::size_t proto_structs::kOneofNpos = -1

inlineconstexpr

Special index value used to indicate oneof without any field set.

Definition at line 64 of file oneof.hpp.