workflow/tutorial/tutorial-03-wget_to_redis.cc

#include <netdb.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <string>
#include "workflow/HttpMessage.h"
#include "workflow/HttpUtil.h"
#include "workflow/RedisMessage.h"
#include "workflow/Workflow.h"
#include "workflow/WFTaskFactory.h"
#include "workflow/WFFacilities.h"

using namespace protocol;

#define REDIRECT_MAX    5
#define RETRY_MAX       2

struct tutorial_series_context
{
	std::string http_url;
	std::string redis_url;
	size_t body_len;
	bool success;
};

void redis_callback(WFRedisTask *task)
{
	int state = task->get_state();
	tutorial_series_context *context =
		(tutorial_series_context *)series_of(task)->get_context();
	RedisValue value;

	if (state == WFT_STATE_SUCCESS)
	{
		task->get_resp()->get_result(value);
		if (!value.is_error())
		{
			fprintf(stderr, "redis SET success: key: %s, value size: %zu\n",
							context->http_url.c_str(), context->body_len);
			context->success = true;
		}
		else
			fprintf(stderr, "redis error reply! Need password?\n");
	}
	else
	{
		fprintf(stderr, "redis SET error: state = %d, error = %d\n",
				state, task->get_error());
	}
}

void http_callback(WFHttpTask *task)
{
	HttpResponse *resp = task->get_resp();
	int state = task->get_state();
	int error = task->get_error();

	if (state != WFT_STATE_SUCCESS)
	{
		fprintf(stderr, "http task error: state = %d, error = %d\n",
						state, error);
		return;
	}

	SeriesWork *series = series_of(task);   /* get the series of this task */
	tutorial_series_context *context =
		(tutorial_series_context *)series->get_context();

	const void *body;
	size_t body_len;

	resp->get_parsed_body(&body, &body_len);
	if (body_len == 0)
	{
		fprintf(stderr, "Error: empty http body!");
		return;
	}

	context->body_len = body_len;

	WFRedisTask *redis_task =
		WFTaskFactory::create_redis_task(context->redis_url, RETRY_MAX,
										 redis_callback);

	std::string value((char *)body, body_len);
	redis_task->get_req()->set_request("SET", { context->http_url, value });
	*series << redis_task; /* equal to series->push_back(redis_task) */
}

int main(int argc, char *argv[])
{
	WFHttpTask *http_task;

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

	struct tutorial_series_context context;

	context.success = false;
	context.http_url = argv[1];
	if (strncasecmp(argv[1], "http://", 7) != 0)
		context.http_url = "http://" + context.http_url;

	context.redis_url = argv[2];
	if (strncasecmp(argv[2], "redis://", 8) != 0 &&
		strncasecmp(argv[2], "rediss://", 9) != 0)
	{
		context.redis_url = "redis://" + context.redis_url;
	}

	http_task = WFTaskFactory::create_http_task(context.http_url,
												REDIRECT_MAX, RETRY_MAX,
												http_callback);
	HttpRequest *req = http_task->get_req();
	req->add_header_pair("Accept", "*/*");
	req->add_header_pair("User-Agent", "Wget/1.14 (linux-gnu)");
	req->add_header_pair("Connection", "close");

	/* Limit the http response size to 20M. */
	http_task->get_resp()->set_size_limit(20 * 1024 * 1024);

	/* no more than 30 seconds receiving http response. */
	http_task->set_receive_timeout(30 * 1000);

	WFFacilities::WaitGroup wait_group(1);

	auto series_callback = [&wait_group](const SeriesWork *series)
	{
		tutorial_series_context *context = (tutorial_series_context *)
											series->get_context();

		if (context->success)
			fprintf(stderr, "Series finished. all success!\n");
		else
			fprintf(stderr, "Series finished. failed!\n");

		/* signal the main() to terminate */
		wait_group.done();
	};

	/* Create a series */
	SeriesWork *series = Workflow::create_series_work(http_task,
													  series_callback);
	series->set_context(&context);
	series->start();

	wait_group.wait();
	return 0;
}