sparkplug::Topic Struct Reference

Represents a parsed Sparkplug B MQTT topic. More...

#include <topic.hpp>

Public Member Functions
std::string	to_string () const
	Converts the topic back to a string.

Static Public Member Functions
static stdx::expected< Topic, std::string >	parse (std::string_view topic_str)
	Parses a Sparkplug B topic string.

Public Attributes
std::string	group_id
	Group ID (topic namespace)
MessageType	message_type
	Message type (NBIRTH, NDATA, etc.)
std::string	edge_node_id
	Edge node identifier.
std::string	device_id
	Device identifier (empty for node-level messages)

Detailed Description

Represents a parsed Sparkplug B MQTT topic.

Sparkplug B topics follow the format:

• spBv1.0/{group_id}/{message_type}/{edge_node_id}[/{device_id}]
• spBv1.0/STATE/{host_id} (for primary application state)

Example Topics

• spBv1.0/Energy/NBIRTH/Gateway01 - Node birth
• spBv1.0/Energy/DBIRTH/Gateway01/Sensor01 - Device birth
• spBv1.0/STATE/ScadaHost1 - Primary application state

Definition at line 47 of file topic.hpp.

Member Function Documentation

parse()

static stdx::expected< Topic, std::string > sparkplug::Topic::parse ( std::string_view  topic_str )

static

Parses a Sparkplug B topic string.

Parameters

topic_str

Topic string to parse

Returns

Parsed Topic on success, error message on failure

Example

auto result = sparkplug::Topic::parse("spBv1.0/Energy/NBIRTH/Gateway01");
if (result) {
  const auto& topic = *result;
  std::cout << "Group: " << topic.group_id << "\n";
}

to_string()

std::string sparkplug::Topic::to_string

(

)

const

Converts the topic back to a string.

Returns

Formatted topic string (e.g., "spBv1.0/Energy/NBIRTH/Gateway01")

Note

May throw if std::format throws (e.g., out of memory), but this is rare.

Member Data Documentation

device_id

std::string sparkplug::Topic::device_id

Device identifier (empty for node-level messages)

Definition at line 51 of file topic.hpp.

edge_node_id

std::string sparkplug::Topic::edge_node_id

Edge node identifier.

Definition at line 50 of file topic.hpp.

group_id

std::string sparkplug::Topic::group_id

Group ID (topic namespace)

Definition at line 48 of file topic.hpp.

message_type

MessageType sparkplug::Topic::message_type

Message type (NBIRTH, NDATA, etc.)

Definition at line 49 of file topic.hpp.

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

• include/sparkplug/topic.hpp