kcenon::network::interfaces::connection_observer Interface Reference

Observer interface for client connection events. More...

#include <connection_observer.h>

Inheritance diagram for kcenon::network::interfaces::connection_observer:

Collaboration diagram for kcenon::network::interfaces::connection_observer:

Public Member Functions
virtual	~connection_observer ()=default
virtual auto	on_receive (std::span< const uint8_t > data) -> void=0
	Called when data is received from the server.
virtual auto	on_connected () -> void=0
	Called when the connection is established.
virtual auto	on_disconnected (std::optional< std::string_view > reason=std::nullopt) -> void=0
	Called when the connection is closed.
virtual auto	on_error (std::error_code ec) -> void=0
	Called when an error occurs.

Detailed Description

Observer interface for client connection events.

This interface provides a unified way to handle all connection-related events through the Observer pattern, replacing the individual callback setters (set_receive_callback, set_connected_callback, etc.).

Design Goals

• Single responsibility: One observer handles all connection events
• Extensibility: New events can be added without breaking changes
• Testability: Easy to mock for unit testing

Thread Safety

• Observer methods may be invoked from I/O threads
• Implementations must be thread-safe if shared across connections

Usage Example

class my_observer : public connection_observer {
public:
    void on_receive(std::span<const uint8_t> data) override {
        // Handle received data
    }
    void on_connected() override {
        // Handle connection established
    }
    void on_disconnected(std::optional<std::string_view> reason) override {
        // Handle disconnection
    }
    void on_error(std::error_code ec) override {
        // Handle error
    }
};
 
auto observer = std::make_shared<my_observer>();
client->set_observer(observer);

See also

i_client

callback_adapter

null_connection_observer

Examples

observer_pattern.cpp.

Definition at line 75 of file connection_observer.h.

Constructor & Destructor Documentation

~connection_observer()

virtual kcenon::network::interfaces::connection_observer::~connection_observer ( )

virtualdefault

Member Function Documentation

on_connected()

virtual auto kcenon::network::interfaces::connection_observer::on_connected ( ) -> void

pure virtual

Called when the connection is established.

This is called after a successful connection to the server.

Implemented in chat_observer, kcenon::network::interfaces::callback_adapter, and kcenon::network::interfaces::null_connection_observer.

on_disconnected()

virtual auto kcenon::network::interfaces::connection_observer::on_disconnected ( std::optional< std::string_view > reason = std::nullopt ) -> void

pure virtual

Called when the connection is closed.

Parameters

reason

Optional reason for the disconnection.

Note

The reason may be empty for normal disconnections.

Implemented in chat_observer, kcenon::network::interfaces::callback_adapter, and kcenon::network::interfaces::null_connection_observer.

on_error()

virtual auto kcenon::network::interfaces::connection_observer::on_error ( std::error_code ec ) -> void

pure virtual

Called when an error occurs.

Parameters

ec	The error code describing the error.

Implemented in chat_observer, kcenon::network::interfaces::callback_adapter, and kcenon::network::interfaces::null_connection_observer.

on_receive()

virtual auto kcenon::network::interfaces::connection_observer::on_receive ( std::span< const uint8_t > data ) -> void

pure virtual

Called when data is received from the server.

Parameters

data	The received data as a span of bytes.

Thread Safety

May be called from I/O threads. Implementation must be thread-safe.

Implemented in chat_observer, kcenon::network::interfaces::callback_adapter, kcenon::network::interfaces::null_connection_observer, and receive_only_observer.

---

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

• include/kcenon/network/interfaces/connection_observer.h