Event source that bridges PostgreSQL LISTEN/NOTIFY to the event bus. More...

#include <postgres_event_source.hpp>

Collaboration diagram for postgres_event_source:

Public Member Functions
	postgres_event_source (database::context ctx, event_bus &bus)
	Constructs a postgres_event_source.

	postgres_event_source (const postgres_event_source &)=delete

postgres_event_source &	operator= (const postgres_event_source &)=delete

template<typename Event >
void	register_mapping (const std::string &entity_name, const std::string &channel_name)
	Register a mapping from entity name to typed domain event.

void	start ()
	Start the event source.

void	stop ()
	Stop the event source.

Detailed Description

Event source that bridges PostgreSQL LISTEN/NOTIFY to the event bus.

This class wraps postgres_listener_service and translates low-level entity_change_event notifications into typed domain events that are published to the event bus.

Components can register their entity-to-event mappings via register_mapping(), enabling the event source to automatically publish the correct typed event when a database notification is received.

Usage:

event_bus bus;
postgres_event_source source(ctx, bus);
 
// Register entity mappings
source.register_mapping<currency_changed_event>("ores.risk.currency",
    "ores_currencies");
 
source.start();

Constructor & Destructor Documentation

◆ postgres_event_source()

postgres_event_source	(	database::context	ctx,
		event_bus &	bus
	)

Constructs a postgres_event_source.

Parameters

ctx	Database context for the listener connection.
bus	Reference to the event bus for publishing events.

Member Function Documentation

◆ register_mapping()

template<typename Event >

void register_mapping	(	const std::string &	entity_name,
		const std::string &	channel_name
	)

Register a mapping from entity name to typed domain event.

When a notification is received for the specified entity, the event source will publish an instance of Event to the bus with the notification's timestamp.

Template Parameters

Event The domain event type to publish (must have a timestamp member).

Parameters

entity_name	The fully qualified entity name (e.g., "ores.risk.currency").
channel_name	The PostgreSQL channel to listen on (e.g., "ores_currencies").

Here is the caller graph for this function:

◆ start()

void start ( )

Start the event source.

Begins listening for PostgreSQL notifications on all registered channels.

◆ stop()

void stop ( )

Stop the event source.

Stops listening for notifications.