#include <GenericMessage.hpp>

Public Member Functions
	GenericMessage ()=default

	GenericMessage (GenericMessage &&)=default

	GenericMessage (const GenericMessage &)=default

GenericMessage &	operator= (const GenericMessage &)=default

int32_t	ID ()

const std::string	ShortName ()

const std::string	LongName ()

template<typename T >
void	createFrom (T &msg)

void	createFrom (const MetaMessage &mm, const std::vector< MetaMessage > &mms) noexcept

void	preVisit (int32_t id, const std::string &shortName, const std::string &longName) noexcept

void	postVisit () noexcept

void	visit (uint32_t id, std::string &&typeName, std::string &&name, bool &v) noexcept

void	visit (uint32_t id, std::string &&typeName, std::string &&name, char &v) noexcept

void	visit (uint32_t id, std::string &&typeName, std::string &&name, int8_t &v) noexcept

void	visit (uint32_t id, std::string &&typeName, std::string &&name, uint8_t &v) noexcept

void	visit (uint32_t id, std::string &&typeName, std::string &&name, int16_t &v) noexcept

void	visit (uint32_t id, std::string &&typeName, std::string &&name, uint16_t &v) noexcept

void	visit (uint32_t id, std::string &&typeName, std::string &&name, int32_t &v) noexcept

void	visit (uint32_t id, std::string &&typeName, std::string &&name, uint32_t &v) noexcept

void	visit (uint32_t id, std::string &&typeName, std::string &&name, int64_t &v) noexcept

void	visit (uint32_t id, std::string &&typeName, std::string &&name, uint64_t &v) noexcept

void	visit (uint32_t id, std::string &&typeName, std::string &&name, float &v) noexcept

void	visit (uint32_t id, std::string &&typeName, std::string &&name, double &v) noexcept

void	visit (uint32_t id, std::string &&typeName, std::string &&name, std::string &v) noexcept

template<typename T >
void	visit (uint32_t &id, std::string &&typeName, std::string &&name, T &value) noexcept

template<class Visitor >
void	accept (uint32_t fieldId, Visitor &visitor)

template<class Visitor >
void	accept (Visitor &visitor)

template<class PreVisitor , class Visitor , class PostVisitor >
void	accept (PreVisitor &&_preVisit, Visitor &&_visit, PostVisitor &&_postVisit)

Detailed Description

GenericMessage is providing an abstraction level to work with concrete messages. Therefore, it is acting as both, a Visitor to turn concrete messages into GenericMessages or as Visitable to access the contained data. GenericMessage would use C++'s std::any type; to allow C++14 compilers, we use the backport from linb::any.

Creating a GenericMessage: There are several ways to create a GenericMessage. The first option is to provide a message specification in ODVD format as result from MessageParser, from which a GenericMessage is created. This instance can then be visited afterwards by, for instance, an instance of ProtoDecoder to set the GenericMessage's actual values.

1) This example demonstrates how to process a given message specification to decode a Proto-encoded byte sequence (in protoEncodedData). The message specification is given in messageSpecification that is parsed from MessageParser. On success, it is tried to decode the Proto-encoded data into a GenericMesssage representing an instance of "MyMessage".

Using a message specification that does not match the serialized Proto data might result in unexpected behavior.

// protoEncodedData is provided from somewhere, i.e., via network for example
std::string protoEncodedData = <...>
std::stringstream sstr{protoEncodedData};
cluon::FromProtoVisitor protoDecoder;
protoDecoder.decodeFrom(sstr);
const char *messageSpecification = R"(
message MyMessage [id = 123] {
   int32 field1 [id = 1];
   int32 field2 [id = 2];
}
cluon::MessageParser mp;
auto retVal = mp.parse(std::string(messageSpecification));
if (cluon::MessageParser::MessageParserErrorCodes::NO_MESSAGEPARSER_ERROR == retVal.second) {
    cluon::GenericMessage gm;
    auto listOfMetaMessages = retVal.first;
    gm.createFrom(listOfMetaMessages[0], listOfMetaMessages);
    // Set values in GenericMessage from protoDecoder.
    gm.accept(protoDecoder);
}

2) This example demonstrates how to turn a given concrete message into a GenericMessage. Afterwards, the GenericMessage can be post-processed with Visitors.

MyMessage msg;
// set some fields in msg.
cluon::GenericMessage gm;
gm.createFrom<MyMessage>(msg);

After an instance of GenericMessage is available, it can be post-processed into various representations:

1) Printing the contained data ("toString"; GenericMessage is being visited):

GenericMessage gm;
// gm is created using one of the aforementioned options.
std::stringstream buffer;
gm.accept([](uint32_t, const std::string &, const std::string &) {},
          [&buffer](uint32_t, std::string &&, std::string &&n, auto v) { buffer << n << " = " << v << std::endl; },
          []() {});
std::cout << buffer.str() << std::endl;

2) Filling the values of another concrete message (GenericMessage is acting as Visitor to another message):

GenericMessage gm;
// gm is created using one of the aforementioned options.
Message msg;
msg.accept(gm);

3) Serialize the GenericMessage gm into a Proto-format:

GenericMessage gm;
// gm is created using one of the aforementioned options.
cluon::ToProtoVisitor protoEncoder;
gm.accept(protoEncoder);
const std::string{protoEncoder.encodedData()};

4) Serialize the GenericMessage gm into JSON:

GenericMessage gm;
// gm is created using one of the aforementioned options.
cluon::ToJSONVisitor j;
gm.accept(j);
std::cout << j.json();

4) Dynamically transforming a given Proto-encoded byte sequence into JSON at runtime:

// protoEncodedData is provided from somewhere, i.e., via network for example
std::string protoEncodedData = <...>
std::stringstream sstr{protoEncodedData};
cluon::FromProtoVisitor protoDecoder;
protoDecoder.decodeFrom(sstr);
const char *messageSpecification = R"(
message MyMessage [id = 123] {
   int32 field1 [id = 1];
   int32 field2 [id = 2];
}
cluon::MessageParser mp;
auto retVal = mp.parse(std::string(messageSpecification));
if (cluon::MessageParser::MessageParserErrorCodes::NO_MESSAGEPARSER_ERROR == retVal.second) {
    cluon::GenericMessage gm;
    auto listOfMetaMessages = retVal.first;
    gm.createFrom(listOfMetaMessages[0], listOfMetaMessages);
    // Set values in GenericMessage from protoDecoder.
    gm.accept(protoDecoder);
}
cluon::ToJSONVisitor j;
gm.accept(j);
std::cout << j.json();

Constructor & Destructor Documentation

◆ GenericMessage() [1/3]

cluon::GenericMessage::GenericMessage ( )

default

◆ GenericMessage() [2/3]

cluon::GenericMessage::GenericMessage ( GenericMessage && )

default

◆ GenericMessage() [3/3]

cluon::GenericMessage::GenericMessage ( const GenericMessage & )

default

Member Function Documentation

◆ accept() [1/3]

template<class Visitor >

void cluon::GenericMessage::accept	(	uint32_t	fieldId,
		Visitor &	visitor
	)

inline

This method allows other instances to visit this GenericMessage for post-processing the contained data on an individual field basis.

Parameters

fieldId	Identifier for the field to visit.
visitor	Instance of the visitor visiting this GenericMessage.

Referenced by cluon::LCMToGenericMessage::getGenericMessage(), cluon::EnvelopeConverter::getJSONFromEnvelope(), cluon::EnvelopeConverter::getProtoEncodedEnvelopeFromJSON(), and visit().

◆ accept() [2/3]

template<class Visitor >

void cluon::GenericMessage::accept ( Visitor & visitor )

inline

This method allows other instances to visit this GenericMessage for post-processing the contained data.

Parameters

visitor Instance of the visitor visiting this GenericMessage.

◆ accept() [3/3]

template<class PreVisitor , class Visitor , class PostVisitor >

void cluon::GenericMessage::accept	(	PreVisitor &&	_preVisit,
		Visitor &&	_visit,
		PostVisitor &&	_postVisit
	)

inline

This method allows other instances to visit this GenericMessage for post-processing the contained data.

Parameters

_preVisit	Instance of the visitor pre-visiting this GenericMessage.
_visit	Instance of the visitor visiting this GenericMessage.
_postVisit	Instance of the visitor post-visiting this GenericMessage.

◆ createFrom() [1/2]

template<typename T >

void cluon::GenericMessage::createFrom ( T & msg )

inline

This methods creates this GenericMessage from a given concrete message.

Parameters

msg	Concrete message used to derive this GenericMessage from.

References mm.

Referenced by createFrom(), cluon::LCMToGenericMessage::getGenericMessage(), cluon::EnvelopeConverter::getJSONFromEnvelope(), and cluon::EnvelopeConverter::getProtoEncodedEnvelopeFromJSON().

◆ createFrom() [2/2]

void cluon::GenericMessage::createFrom	(	const MetaMessage &	mm,
		const std::vector< MetaMessage > &	mms
	)

noexcept

This method creates an empty GenericMessage from a given message specification parsed from MessageParser.

Parameters

mm	MetaMessage describing the fields for the message to be resolved.
mms	List of MetaMessages that are known (used for resolving nested message).

◆ ID()

int32_t cluon::GenericMessage::ID ( )

References cluon::MetaMessage::messageIdentifier().

◆ LongName()

const std::string cluon::GenericMessage::LongName ( )

References cluon::MetaMessage::messageName(), and cluon::MetaMessage::packageName().

Referenced by ShortName().

◆ operator=()

GenericMessage& cluon::GenericMessage::operator= ( const GenericMessage & )

default

◆ postVisit()

void cluon::GenericMessage::postVisit ( )

noexcept

◆ preVisit()

void cluon::GenericMessage::preVisit	(	int32_t	id,
		const std::string &	shortName,
		const std::string &	longName
	)

noexcept

◆ ShortName()

const std::string cluon::GenericMessage::ShortName ( )

References LongName().

◆ visit() [1/14]

void cluon::GenericMessage::visit	(	uint32_t	id,
		std::string &&	typeName,
		std::string &&	name,
		bool &	v
	)

noexcept

◆ visit() [2/14]

void cluon::GenericMessage::visit	(	uint32_t	id,
		std::string &&	typeName,
		std::string &&	name,
		char &	v
	)

noexcept

◆ visit() [3/14]

void cluon::GenericMessage::visit	(	uint32_t	id,
		std::string &&	typeName,
		std::string &&	name,
		int8_t &	v
	)

noexcept

◆ visit() [4/14]

void cluon::GenericMessage::visit	(	uint32_t	id,
		std::string &&	typeName,
		std::string &&	name,
		uint8_t &	v
	)

noexcept

◆ visit() [5/14]

void cluon::GenericMessage::visit	(	uint32_t	id,
		std::string &&	typeName,
		std::string &&	name,
		int16_t &	v
	)

noexcept

◆ visit() [6/14]

void cluon::GenericMessage::visit	(	uint32_t	id,
		std::string &&	typeName,
		std::string &&	name,
		uint16_t &	v
	)

noexcept

◆ visit() [7/14]

void cluon::GenericMessage::visit	(	uint32_t	id,
		std::string &&	typeName,
		std::string &&	name,
		int32_t &	v
	)

noexcept

◆ visit() [8/14]

void cluon::GenericMessage::visit	(	uint32_t	id,
		std::string &&	typeName,
		std::string &&	name,
		uint32_t &	v
	)

noexcept

◆ visit() [9/14]

void cluon::GenericMessage::visit	(	uint32_t	id,
		std::string &&	typeName,
		std::string &&	name,
		int64_t &	v
	)

noexcept

◆ visit() [10/14]

void cluon::GenericMessage::visit	(	uint32_t	id,
		std::string &&	typeName,
		std::string &&	name,
		uint64_t &	v
	)

noexcept

◆ visit() [11/14]

void cluon::GenericMessage::visit	(	uint32_t	id,
		std::string &&	typeName,
		std::string &&	name,
		float &	v
	)

noexcept

◆ visit() [12/14]

void cluon::GenericMessage::visit	(	uint32_t	id,
		std::string &&	typeName,
		std::string &&	name,
		double &	v
	)

noexcept

◆ visit() [13/14]

void cluon::GenericMessage::visit	(	uint32_t	id,
		std::string &&	typeName,
		std::string &&	name,
		std::string &	v
	)

noexcept

◆ visit() [14/14]

template<typename T >

void cluon::GenericMessage::visit	(	uint32_t &	id,
		std::string &&	typeName,
		std::string &&	name,
		T &	value
	)

inlinenoexcept

References accept().

Public Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ GenericMessage() [1/3]

◆ GenericMessage() [2/3]

◆ GenericMessage() [3/3]

Member Function Documentation

◆ accept() [1/3]

◆ accept() [2/3]

◆ accept() [3/3]

◆ createFrom() [1/2]

◆ createFrom() [2/2]

◆ ID()

◆ LongName()

◆ operator=()

◆ postVisit()

◆ preVisit()

◆ ShortName()

◆ visit() [1/14]

◆ visit() [2/14]

◆ visit() [3/14]

◆ visit() [4/14]

◆ visit() [5/14]

◆ visit() [6/14]

◆ visit() [7/14]

◆ visit() [8/14]

◆ visit() [9/14]

◆ visit() [10/14]

◆ visit() [11/14]

◆ visit() [12/14]

◆ visit() [13/14]

◆ visit() [14/14]