dfx::Core::DataMessage Class Reference

Data-plane message containing an owned byte buffer. More...

#include <dfx-core/messages/DataMessage.hpp>

Inheritance diagram for dfx::Core::DataMessage:

Collaboration diagram for dfx::Core::DataMessage:

Public Member Functions
std::vector< uint8_t > const &	data () const noexcept
	Access the payload buffer.
std::vector< uint8_t >	takeData () noexcept
	Move the payload buffer out of the message.
Kind	kind () const override
	This message belongs to the data-plane connectivity domain.
MessagePtr	clone () const override
	Clone this message (deep copy).
Public Member Functions inherited from dfx::Core::Message
	DISABLE_COPY_AND_MOVE (Message)
	Messages are non-copyable and non-movable.
virtual	~Message ()
	Virtual destructor.
template<typename Clock = std::chrono::steady_clock> requires std::chrono::is_clock_v<Clock>
std::chrono::time_point< Clock, std::chrono::microseconds >	timestampToTimePoint () const noexcept
	Convert timestamp() into a time_point of the given clock type.
void	addToPathTaken (std::string path)
	Append one hop to the message path trace.
template<DerivedFromMessage T>
bool	is () const noexcept
	Check whether this message is of a given derived type.
template<DerivedFromMessage T>
T &	as () noexcept
	Cast this message to a derived type (unchecked).
template<DerivedFromMessage T>
T const &	as () const noexcept
	Cast this message to a derived type (unchecked).
Utils::UUID const &	uuid () const noexcept
	Unique identifier of this message instance.
Utils::UUID const &	parentUuid () const noexcept
	UUID of the parent message if created from one, otherwise default UUID value.
std::vector< std::string > const &	pathTaken () const noexcept
	Sequence of "node.port" hops this message has traversed.
std::chrono::microseconds	timestamp () const noexcept
	Construction timestamp in microseconds since timestampClock epoch. This is not "wall clock time" unless timestampClock is CLOCK_REALTIME.
bool	hasMimeType () const noexcept
	Whether the message carries an explicit MIME type.
MimeType	mimeType () const noexcept
	Get the message MIME type. If no explicit MIME type is set, returns dfx::Core::MimeType::OctetStream.
void	setMimeType (MimeType mimeType)
	Set the message MIME type.
void	resetMimeType ()
	Clear the explicit MIME type (message then defaults to octet-stream).

Protected Member Functions
void	cloneFromBase (Message const &base) override
	Copy base and derived state from base into this instance.
	DataMessage (std::vector< uint8_t > data, MessagePtr const &parent=nullptr)
	Construct a data message with a payload, optionally inheriting from a parent.
	DataMessage (std::vector< uint8_t > data, MimeType mimeType, MessagePtr const &parent=nullptr)
	Construct a data message with payload and explicit MIME type.
	Message (MessagePtr const &parent=nullptr)
	Construct a message, optionally inheriting state from a parent message.
	Message (MimeType mimeType, MessagePtr const &parent=nullptr)
	Construct a message with an explicit MIME type, optionally inheriting from a parent.
Protected Member Functions inherited from dfx::Core::Message
	Message (MessagePtr const &parent=nullptr)
	Construct a message, optionally inheriting state from a parent message.
	Message (MimeType mimeType, MessagePtr const &parent=nullptr)
	Construct a message with an explicit MIME type, optionally inheriting from a parent.

Friends
class	Message

Additional Inherited Members
Static Public Member Functions inherited from dfx::Core::Message
template<DerivedFromMessage T, typename ... Args>
static std::unique_ptr< T >	create (Args &&... args)
	Convenience allocator for derived message types.
Static Public Attributes inherited from dfx::Core::Message
static clockid_t	timestampClock
	Clock used by the constructor to capture timestamps.

Detailed Description

Data-plane message containing an owned byte buffer.

Payload ownership

The message owns its payload buffer:

• data() returns a const view of the internal std::vector<uint8_t>.
• takeData() moves the buffer out, leaving the message with an empty payload.

MIME type

MIME type is handled by the base Message :

• The constructor overload that takes a MimeType sets an explicit MIME type (Message(mimeType, parent)).
• The other overload inherits base state from parent (UUID parent link, and optional MIME type) but does not force a MIME type.

Note

The base class forbids MimeType::Any on messages (asserted in Message).

Cloning

clone() produces a new DataMessage and copies:

• all base fields via Message::cloneFromBase(...)
• the payload buffer (_data)

Note

In dfx, fan-out delivery relies on cloning so each channel gets an independent message instance.

Constructor & Destructor Documentation

DataMessage() [1/2]

dfx::Core::DataMessage::DataMessage ( std::vector< uint8_t > data, MessagePtr const & parent = nullptr )

protected

Construct a data message with a payload, optionally inheriting from a parent.

Parameters

data	Payload bytes (moved into the message).
parent	Optional parent message. Base state (parent UUID, and optional MIME type) is inherited from the parent via Message(parent).

DataMessage() [2/2]

dfx::Core::DataMessage::DataMessage ( std::vector< uint8_t > data, MimeType mimeType, MessagePtr const & parent = nullptr )

protected

Construct a data message with payload and explicit MIME type.

Parameters

data	Payload bytes (moved into the message).
mimeType	Explicit MIME type to assign (must not be Any, asserted by Message).
parent	Optional parent message whose UUID/MIME-type are inherited.

Member Function Documentation

clone()

MessagePtr dfx::Core::DataMessage::clone ( ) const

overridevirtual

Clone this message (deep copy).

The clone copies the base state and duplicates the payload vector.

Returns

A new message instance of the same dynamic type.

Implements dfx::Core::Message.

cloneFromBase()

void dfx::Core::DataMessage::cloneFromBase ( Message const & base )

overrideprotectedvirtual

Copy base and derived state from base into this instance.

Calls Message::cloneFromBase(base) then copies the payload from base.as<DataMessage>()._data.

Reimplemented from dfx::Core::Message.

data()

std::vector< uint8_t > const & dfx::Core::DataMessage::data ( ) const

inlinenoexcept

Access the payload buffer.

Returns

A const reference to the owned byte vector.

kind()

Kind dfx::Core::DataMessage::kind ( ) const

inlineoverridevirtual

This message belongs to the data-plane connectivity domain.

Implements dfx::Core::Message.

Message() [1/2]

dfx::Core::Message::Message ( MessagePtr const & parent = nullptr )

protected

Construct a message, optionally inheriting state from a parent message.

Captures a timestamp and generates a new UUID.

If parent is non-null:

• parentUuid() becomes the parent's UUID
• MIME type (if any) is inherited

Parameters

parent

Optional parent message (non-owning reference through pointer).

Message() [2/2]

dfx::Core::Message::Message ( MimeType mimeType, MessagePtr const & parent = nullptr )

protected

Construct a message with an explicit MIME type, optionally inheriting from a parent.

Equivalent to Message(MessagePtr const&) followed by setMimeType.

Parameters

mimeType	Concrete MIME type to assign (must not be Any, asserted).
parent	Optional parent message.

takeData()

std::vector< uint8_t > dfx::Core::DataMessage::takeData ( )

inlinenoexcept

Move the payload buffer out of the message.

After this call, the message’s internal payload becomes empty.

Returns

The owned byte vector (moved).

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

• lib/dfx-core/messages/DataMessage.hpp