Numeric Operations in Redis

#include <boost/redis.hpp>
#include <boost/asio/io_context.hpp>
#include <boost/asio/detached.hpp>
#include <boost/asio/consign.hpp>
#include <optional>
#include <iostream>

#include <boost/redis/src.hpp>

namespace net = boost::asio;
using boost::redis::connection;
using boost::redis::config;
using boost::redis::logger;
using boost::redis::request;
using boost::redis::response;

int main() {
    try {
        net::io_context ioc;

        // Create a shared connection object
        auto conn = std::make_shared<connection>(ioc.get_executor());

        config cfg; // defaults: 127.0.0.1:6379
        conn->async_run(cfg, logger{logger::level::disabled},
                        net::consign(net::detached, conn));

        // Prepare Redis commands to set and modify numeric values
        request req;
        req.push("SET", "count", "5");
        req.push("SET", "completion_rate", "95.5");
        req.push("SET", "duration", "0");

        // Perform numeric operations
        req.push("DECR", "count");
        req.push("INCRBYFLOAT", "completion_rate", "1.5");
        req.push("INCR", "duration");

        // Retrieve the updated values
        req.push("GET", "count");
        req.push("GET", "completion_rate");
        req.push("GET", "duration");

        response<
            std::string, std::string, std::string,
            std::int64_t, double, std::int64_t,
            std::optional<std::string>, std::optional<std::string>, std::optional<std::string>
        > resp;

        conn->async_exec(req, resp,
            [conn, &resp](boost::system::error_code ec, std::size_t) {
                if (!ec) {
                    // Print SET response (first one shown as example)
                    std::cout << "SET count: " << std::get<0>(resp).value() << "\n";
                    // Other SET responses can be retrieved similarly from indices 1 and 2

                    // Print operation response (first one shown as example)
                    std::cout << "DECR count: " << std::get<3>(resp).value() << "\n";
                    // Other operation responses can be retrieved similarly from indices 4 and 5

                    // Print GET responses
                    if (auto& count = std::get<6>(resp); count && count.value()) {
                        std::cout << "Course count: " << *count.value() << "\n";
                    } else {
                        std::cout << "Course count: (nil)\n";
                    }

                    if (auto& rate = std::get<7>(resp); rate && rate.value()) {
                        std::cout << "Completion rate: " << *rate.value() << "\n";
                    } else {
                        std::cout << "Completion rate: (nil)\n";
                    }

                    // Other GET responses can be retrieved similarly from index 8
                } else {
                    std::cerr << "Error executing Redis commands: "
                              << ec.message() << "\n";
                }
                conn->cancel();
            });

        ioc.run();
    } catch (const std::exception& e) {
        std::cerr << "Exception: " << e.what() << "\n";
        return 1;
    }
    return 0;
}