RSS Feed를 가져오는 C# 예제를 통한 Async 효율성 테스트

RSS Feed를 가져오는 C# 예제를 통한 Async 효율성 테스트

using System;

using System.Collections.Generic;

using System.Diagnostics;

using System.Linq;

using System.Net;

using System.Net.Cache;

using System.Text;

using System.Threading.Tasks;

using System.Xml.Linq;

namespace FeedReader

{

    class Program

    {

        static void Main(string[] args)

        {

            var feedUrls = new List<string>()

            {

                "http://www.engadget.com/rss.xml",

                //"http://www.wired.com/feed/",

                "http://apod.nasa.gov/apod.rss",

                "http://arstechnica.com/feed/",

            };

            var stopwatch = Stopwatch.StartNew();

            var feeds = (from url in feedUrls select ReadFeed(url)).ToArray();

            var items = from feed in feeds

                        from channel in XElement.Parse(feed).Elements("channel")

                        from item in channel.Elements("item").Take(2)

                        let date = PublishedData(item)

                        orderby date descending

                        select new

                        {

                            Title = (string)channel.Element("title"),

                            Link = (string)channel.Element("link"),

                            PostTitle = (string)item.Element("title"),

                            PostLink = (string)item.Element("link"),

                            Date = date

                        };

            foreach (var item in items)

            {

                Console.WriteLine("Title : {0} [{1}]", item.Title, item.Link);

                Console.WriteLine("    Post : {0} [{1}]", item.PostTitle, item.PostLink);

                Console.WriteLine("    Date : {0}", item.Date);

                Console.WriteLine("----------------------");

            }

            Console.WriteLine("Total Time: {0}",stopwatch.Elapsed);

            Console.ReadKey();

        }

      

        static string ReadFeed(string url)

        {

            var client = new WebClient()

            {

                CachePolicy = new RequestCachePolicy(RequestCacheLevel.NoCacheNoStore)

            };

            var contents = client.DownloadString(url);

            return contents;

        }

        static DateTime PublishedData(XElement item)

        {

            var s = (string)item.Element("pubDate");

            if (s != null)

            {

                s = s.Replace("EST", "-0500");

                s = s.Replace("EDT", "-0400");

                s = s.Replace("CST", "-0600");

                s = s.Replace("CDT", "-0500");

                s = s.Replace("MST", "-0700");

                s = s.Replace("MDT", "-0600");

                s = s.Replace("PST", "-0800");

                s = s.Replace("PDT", "-0700");

            }

            DateTime d;

            if (DateTime.TryParse(s, out d))

            {

                return d;

            }

            return DateTime.MinValue;

        }

    }

}

using System;

using System.Collections.Generic;

using System.Diagnostics;

using System.Linq;

using System.Net;

using System.Net.Cache;

using System.Threading.Tasks;

using System.Xml.Linq;

namespace FeedReader

{

    class Program

    {

        static void Main(string[] args)

        {

            ProcessFeedsAsync(args).Wait();

            Console.ReadKey();

        }

        static async Task ProcessFeedsAsync(string[] args)

        {

            var feedUrls = new List<string>()

            {

                "http://www.engadget.com/rss.xml",

                //"http://www.wired.com/feed/",

                "http://apod.nasa.gov/apod.rss",

                "http://arstechnica.com/feed/",

            };

            var stopwatch = Stopwatch.StartNew();

            var feeds = await Task.WhenAll(from url in feedUrls select ReadFeed(url));

            var items = from feed in feeds

                        from channel in XElement.Parse(feed).Elements("channel")

                        from item in channel.Elements("item").Take(2)

                        let date = PublishedData(item)

                        orderby date descending

                        select new

                        {

                            Title = (string)channel.Element("title"),

                            Link = (string)channel.Element("link"),

                            PostTitle = (string)item.Element("title"),

                            PostLink = (string)item.Element("link"),

                            Date = date

                        };

            foreach (var item in items)

            {

                Console.WriteLine("Title : {0} [{1}]", item.Title, item.Link);

                Console.WriteLine("    Post : {0} [{1}]", item.PostTitle, item.PostLink);

                Console.WriteLine("    Date : {0}", item.Date);

                Console.WriteLine("----------------------");

            }

            Console.WriteLine("Total Time: {0}",stopwatch.Elapsed);

        }

      

        static Task<string> ReadFeed(string url)

        {

            var client = new WebClient()

            {

                CachePolicy = new RequestCachePolicy(RequestCacheLevel.NoCacheNoStore)

            };

            var contents = client.DownloadStringTaskAsync(url);

            return contents;

        }

        static DateTime PublishedData(XElement item)

        {

            var s = (string)item.Element("pubDate");

            if (s != null)

            {

                s = s.Replace("EST", "-0500");

                s = s.Replace("EDT", "-0400");

                s = s.Replace("CST", "-0600");

                s = s.Replace("CDT", "-0500");

                s = s.Replace("MST", "-0700");

                s = s.Replace("MDT", "-0600");

                s = s.Replace("PST", "-0800");

                s = s.Replace("PDT", "-0700");

            }

            DateTime d;

            if (DateTime.TryParse(s, out d))

            {

                return d;

            }

            return DateTime.MinValue;

        }

    }

}

Async 처리로 RSS feed를 가져오는 경우 테스트 PC에서의 경우 약 4배정도 속도 차가 있음

참고

https://msdn.microsoft.com/ko-kr/library/hh191443(v=vs.110).aspx

https://msdn.microsoft.com/ko-kr/magazine/jj991977(en-us).aspx