workflow/tutorial/tutorial-10-user_defined_protocol/client.cc

#include <string.h>
#include <stdio.h>
#include <mutex>
#include <condition_variable>
#include "workflow/Workflow.h"
#include "workflow/WFTaskFactory.h"
#include "message.h"

using WFTutorialTask = WFNetworkTask<protocol::TutorialRequest,
									 protocol::TutorialResponse>;
using tutorial_callback_t = std::function<void (WFTutorialTask *)>;

using namespace protocol;

class MyFactory : public WFTaskFactory
{
public:
	static WFTutorialTask *create_tutorial_task(const std::string& host,
												unsigned short port,
												int retry_max,
												tutorial_callback_t callback)
	{
		using NTF = WFNetworkTaskFactory<TutorialRequest, TutorialResponse>;
		WFTutorialTask *task = NTF::create_client_task(TT_TCP, host, port,
													   retry_max,
													   std::move(callback));
		task->set_keep_alive(30 * 1000);
		return task;
	}
};

int main(int argc, char *argv[])
{
	std::mutex mutex;
	std::condition_variable cond;
	bool finished = false;
	unsigned short port;
	std::string host;

	if (argc != 3)
	{
		fprintf(stderr, "USAGE: %s <host> <port>\n", argv[0]);
		exit(1);
	}

	host = argv[1];
	port = atoi(argv[2]);
	std::function<void (WFTutorialTask *task)> callback =
		[&host, port, &callback](WFTutorialTask *task) {
		int state = task->get_state();
		int error = task->get_error();
		TutorialResponse *resp = task->get_resp();
		char buf[1024];
		void *body;
		size_t body_size;

		if (state != WFT_STATE_SUCCESS)
		{
			if (state == WFT_STATE_SYS_ERROR)
				fprintf(stderr, "SYS error: %s\n", strerror(error));
			else if (state == WFT_STATE_DNS_ERROR)
				fprintf(stderr, "DNS error: %s\n", gai_strerror(error));
			else
				fprintf(stderr, "other error.\n");
			return;
		}

		resp->get_message_body_nocopy(&body, &body_size);
		if (body_size != 0)
			printf("Server Response: %.*s\n", (int)body_size, (char *)body);

		printf("Input next request string (Ctrl-D to exit): ");
		*buf = '\0';
		scanf("%1023s", buf);
		body_size = strlen(buf);
		if (body_size > 0)
		{
			WFTutorialTask *next;
			next = MyFactory::create_tutorial_task(host, port, 0, callback);
			next->get_req()->set_message_body(buf, body_size);
			next->get_resp()->set_size_limit(4 * 1024);
			**task << next; /* equal to: series_of(task)->push_back(next) */
		}
		else
			printf("\n");
	};

	/* First request is emtpy. We will ignore the server response. */
	WFTutorialTask *task = MyFactory::create_tutorial_task(host, port, 0, callback);
	task->get_resp()->set_size_limit(4 * 1024);
	Workflow::start_series_work(task, [&mutex, &cond, &finished](const SeriesWork *)
	{
		mutex.lock();
		finished = true;
		cond.notify_one();
		mutex.unlock();
	});

	std::unique_lock<std::mutex> lock(mutex);
	while (!finished)
		cond.wait(lock);

	lock.unlock();
	return 0;
}