C++ APISession methods

set_panel_event_callback

Registers the local handler for server-sent panel events.

set_panel_event_callback installs the local handler for server-sent panel events.

Function variants

void set_panel_event_callback(std::function<void(blaze::panel_event)> callback);

Runs on the library I/O thread

Do not call synchronous blaze::session methods from this callback. If you need to continue work from here, stay on async API or hand control back to your own thread/executor.

Callback signature

void(blaze::panel_event event)

Callback payload

struct panel_event {
  blaze::event_type type;
  std::unordered_map<std::string, std::string> content;
};

Prop

Type

Behavior notes

  • This method only installs the local event handler.
  • To actually receive panel events from the server, also call enable_panel_events(true).
  • If the callback is not set, panel-event subscription can still succeed, but incoming events are ignored by the library.
  • The callback is invoked only for successfully parsed panel events.
  • Once registered, this callback stays attached to the same blaze::session object until you replace or clear it.
  • Protocol/parse failures in the panel-event receive path do not invoke this callback. They surface through set_exception_callback(...) and then session shutdown.
  • If panel-event subscription was active before valid session resumption, delivery continues after resumption on the same session.
  • Event types and payloads are documented in Panel events overview and Event types.
  • Pass nullptr or an empty std::function to clear the callback.

Example

Compilation note

This example compiles in the same form from C++14 to C++26.

#include "blazeauth/api/api.hpp"

#include <iostream>
#include <string>
#include <system_error>

void print_error_code(const std::string& context, const std::error_code& ec) {
  std::cout << context << ": " << ec.message() << " ("
            << ec.value() << " : " << ec.category().name() << ")\n";
}

std::string read_line(const std::string& label) {
  std::string value;
  std::cout << label << ": ";
  std::getline(std::cin, value);
  return value;
}

void print_status(const std::string& context, blaze::status status) {
  std::cout << context << ": "
            << static_cast<unsigned int>(status)
            << " (" << blaze::to_string(status) << ")\n";
}

int main() {
  const std::string websocket_api_key = read_line("Websocket API key");
  const std::string client_id = read_line("Client ID");

  blaze::session session;

  session.set_panel_event_callback([](blaze::panel_event event) {
    std::cout << "Panel event type: "
              << static_cast<unsigned int>(event.type) << '\n';

    for (const auto& entry : event.content) {
      std::cout << "  " << entry.first << " = " << entry.second << '\n';
    }
  });

  try {
    const blaze::api_server server = session.connect();
    std::cout << "Connected to server location: " << server.location << '\n';

    const blaze::application app = session.initialize(websocket_api_key, client_id);
    if (!app.good()) {
      print_status("Initialize returned status", app.status);
      return 1;
    }

    const blaze::status enable_status = session.enable_panel_events(true);
    if (enable_status != blaze::status::ok) {
      print_status("Enable-panel-events returned status", enable_status);
      return 1;
    }

    std::cout << "Panel events enabled. Press Enter to stop listening.\n";
    std::string line;
    std::getline(std::cin, line);

    const blaze::status disable_status = session.enable_panel_events(false);
    if (disable_status != blaze::status::ok) {
      print_status("Disable-panel-events returned status", disable_status);
      return 1;
    }

    session.shutdown();
  } catch (const std::system_error& e) {
    print_error_code("Panel-event flow failed", e.code());
    return 1;
  }

  return 0;
}

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