DotnetSpider

DotnetSpider, a .NET Standard web crawling library similar to WebMagic and Scrapy. It is a lightweight ,efficient and fast high-level web crawling & scraping framework for .NET

DESIGN

DEVELOP ENVIROMENT

• Visual Studio 2017(15.3 or later)
• .NET Core 2.0

OPTIONAL ENVIROMENT

• Storage data to mysql. Download MySql

    grant all on *.* to 'root'@'localhost' IDENTIFIED BY '' with grant option;
  
    flush privileges;
  

• Run distributed crawler. Download Redis for windows

• SqlServer.

• PostgreSQL.

• Cassandra

SAMPLES

Please see the Projet DotnetSpider.Sample in the solution.

BASE USAGE

Base usage Codes

Crawler pages traversal

	public static void CrawlerPagesTraversal()
	{
		// Config encoding, header, cookie, proxy etc... 定义采集的 Site 对象, 设置 Header、Cookie、代理等
		var site = new Site { EncodingName = "UTF-8", RemoveOutboundLinks = true };

		// Set start/seed url
		site.AddStartUrl("http://www.cnblogs.com/");

		Spider spider = Spider.Create(site,
			// crawler identity
			"cnblogs",
			// use memoery queue scheduler
			new QueueDuplicateRemovedScheduler(),
			// default page processor will save whole html, and extract urls to target urls via regex
			new DefaultPageProcessor(new[] { "cnblogs\\.com" }))
			// save crawler result to file in the folder: \{running directory}\data\{crawler identity}\{guid}.dsd
			.AddPipeline(new FilePipeline());

		// dowload html by http client
		spider.Downloader = new HttpClientDownloader();
		// 4 threads 4线程
		spider.ThreadNum = 4;
		// traversal deep 遍历深度
		spider.Deep = 3;

		// stop crawler if it can't get url from the scheduler after 30000 ms 当爬虫连续30秒无法从调度中心取得需要采集的链接时结束.
		spider.EmptySleepTime = 30000;

		// start crawler 启动爬虫
		spider.Run();
	}

Custmize processor and pipeline

	public static void CustmizeProcessorAndPipeline()
	{
		// Config encoding, header, cookie, proxy etc... 定义采集的 Site 对象, 设置 Header、Cookie、代理等
		var site = new Site { EncodingName = "GB2312", RemoveOutboundLinks = true };
		//for (int i = 1; i < 5; ++i)
		//{
		//	// Add start/feed urls. 添加初始采集链接
		//	site.AddStartUrl("http://" + $"www.youku.com/v_olist/c_97_g__a__sg__mt__lg__q__s_1_r_0_u_0_pt_0_av_0_ag_0_sg__pr__h__d_1_p_{i}.html");
		//}
		site.AddStartUrl("http://www.unistrong.com/");
		Spider spider = Spider.Create(site,
			// use memoery queue scheduler. 使用内存调度
			new QueueDuplicateRemovedScheduler(),
			// use custmize processor for youku 为优酷自定义的 Processor
			new YoukuPageProcessor())
			// use custmize pipeline for youku 为优酷自定义的 Pipeline
			.AddPipeline(new YoukuPipeline());
		spider.Downloader = new HttpClientDownloader();
		spider.ThreadNum = 1;
		spider.EmptySleepTime = 3000;

		// Start crawler 启动爬虫
		spider.Run();

	}

	public class YoukuPipeline : BasePipeline
	{
		private static long count = 0;

		public override void Process(params ResultItems[] resultItems)
		{
			foreach (var resultItem in resultItems)
			{
				StringBuilder builder = new StringBuilder();
				foreach (YoukuVideo entry in resultItem.Results["VideoResult"])
				{
					count++;
					builder.Append($" [YoukuVideo {count}] {entry.Name}");
				}
				Console.WriteLine(builder);
			}

			// Other actions like save data to DB. 可以自由实现插入数据库或保存到文件
		}
	}

	public class YoukuPageProcessor : BasePageProcessor
	{
		protected override void Handle(Page page)
		{
			// 利用 Selectable 查询并构造自己想要的数据对象
			var totalVideoElements = page.Selectable.SelectList(Selectors.XPath("//div[@class='yk-pack pack-film']")).Nodes();
			List<YoukuVideo> results = new List<YoukuVideo>();
			foreach (var videoElement in totalVideoElements)
			{
				var video = new YoukuVideo();
				video.Name = videoElement.Select(Selectors.XPath(".//img[@class='quic']/@alt")).GetValue();
				results.Add(video);
			}

			// Save data object by key. 以自定义KEY存入page对象中供Pipeline调用
			page.AddResultItem("VideoResult", results);

			// Add target requests to scheduler. 解析需要采集的URL
			//foreach (var url in page.Selectable.SelectList(Selectors.XPath("//ul[@class='yk-pages']")).Links().Nodes())
			//{
			//	page.AddTargetRequest(new Request(url.GetValue(), null));
			//}
		}
	}

	public class YoukuVideo
	{
		public string Name { get; set; }
	}

ADDITIONAL USAGE

Configurable Entity Spider

View compelte Codes

public class JdSkuSampleSpider : EntitySpider
{
	public JdSkuSampleSpider() : base("JdSkuSample", new Site
	{
		//HttpProxyPool = new HttpProxyPool(new KuaidailiProxySupplier("快代理API"))
	})
	{
	}

	protected override void MyInit(params string[] arguments)
	{
		ThreadNum = 1;
		// dowload html by http client
		Downloader = new HttpClientDownloader();

		// storage data to mysql, default is mysql entity pipeline, so you can comment this line. Don't miss sslmode.
		AddPipeline(new MySqlEntityPipeline("Database='mysql';Data Source=localhost;User ID=root;Password=;Port=3306;SslMode=None;"));
		AddStartUrl("http://list.jd.com/list.html?cat=9987,653,655&page=2&JL=6_0_0&ms=5#J_main", new Dictionary<string, object> { { "name", "手机" }, { "cat3", "655" } });
		AddEntityType(typeof(Product));
	}

	[Table("test", "jd_sku", TableSuffix.Monday, Indexs = new[] { "Category" }, Uniques = new[] { "Category,Sku", "Sku" })]
	[EntitySelector(Expression = "//li[@class='gl-item']/div[contains(@class,'j-sku-item')]")]
	[TargetUrlsSelector(XPaths = new[] { "//span[@class=\"p-num\"]" }, Patterns = new[] { @"&page=[0-9]+&" })]
	public class Product : SpiderEntity
	{
		[PropertyDefine(Expression = "./@data-sku", Length = 100)]
		public string Sku { get; set; }

		[PropertyDefine(Expression = "name", Type = SelectorType.Enviroment, Length = 100)]
		public string Category { get; set; }

		[PropertyDefine(Expression = "cat3", Type = SelectorType.Enviroment)]
		public int CategoryId { get; set; }

		[PropertyDefine(Expression = "./div[1]/a/@href")]
		public string Url { get; set; }

		[PropertyDefine(Expression = "./div[5]/strong/a")]
		public long CommentsCount { get; set; }

		[PropertyDefine(Expression = ".//div[@class='p-shop']/@data-shop_name", Length = 100)]
		public string ShopName { get; set; }

		[PropertyDefine(Expression = ".//div[@class='p-name']/a/em", Length = 100)]
		public string Name { get; set; }

		[PropertyDefine(Expression = "./@venderid", Length = 100)]
		public string VenderId { get; set; }

		[PropertyDefine(Expression = "./@jdzy_shop_id", Length = 100)]
		public string JdzyShopId { get; set; }

		[PropertyDefine(Expression = "Monday", Type = SelectorType.Enviroment)]
		public DateTime RunId { get; set; }
	}
}

public static void Main()
{
	Startup.Run(new string[] { "-s:JdSkuSample", "-tid:JdSkuSample", "-i:guid" });
}

Startup configuration

Command: -s:[spider type name] -i:[identity] -a:[arg1,arg2...] -tid:[taskId] -n:[name] -e:[en1=value1,en2=value2,...]

1. -s: Type name of spider or TaskNameAttribute for example: DotnetSpider.Sample.BaiduSearchSpiderl
2. -i: Set identity.
3. -a: Pass arguments to spider's Run method.
4. -tid: Set task id.
5. -n: Set name.
6. -c: Set config file path, for example you want to run with a customize config: -e:app.my.config

WebDriver Support

When you want to collect a page JS loaded, there is only one thing to do, set the downloader to WebDriverDownloader.

Downloader=new WebDriverDownloader(Browser.Chrome);

See a complete sample

NOTE:

1. Make sure there is a ChromeDriver.exe in bin forlder when you try to use Chrome. You can contain it to your project via NUGET manager: Chromium.ChromeDriver
2. Make sure you already add a *.webdriver Firefox profile when you try to use Firefox: https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles
3. Make sure there is a PhantomJS.exe in bin folder when you try to use PhantomJS. You can contain it to your project via NUGET manager: PhantomJS

Monitor and Database log

1. Set SystemConnection in app.config
2. Update nlog.config like https://github.com/dotnetcore/DotnetSpider/blob/master/src/DotnetSpider.Extension.Test/nlog.config

Web Manager

NOTICE

when you use redis scheduler, please update your redis config:

timeout 0 
tcp-keepalive 60

Comments

• EntitSpider定义的表名和列名全部小写化, 以备不同数据库间转换或者MYSQL win/linux的切换
• 允许不添加Pipeline执行爬虫

AREAS FOR IMPROVEMENTS

QQ Group: 477731655 Email: [email protected]