面向電子商務網站的專業網絡爬蟲設計與實現

論文字數:14299,頁數:27 有開題報告，任務書

摘   要
    網絡爬蟲是一個自動下載網頁的程序，是搜索引擎的重要組成。傳統爬蟲從一個或若干初始網頁的URL開始，獲得初始網頁上的URL，在抓取網頁的過程中，不斷從當前頁面上抽取新的URL放入隊列，直到該URL對列為空為止。
    本文設計的這款面向電子商務網站的專業網絡爬蟲，只對電子商務網站進行信息搜索，讓用戶可以盡可能多的找到自己關心的商品信息。面向電子商務網站的專業網絡爬蟲的工作流程十分復雜，需要根據一定的網頁分析過濾與電子商務商品信息無關的鏈接，保留有用的鏈接并將其放入等待抓取的URL隊列。然后，它將根據一定的搜索策略從隊列中選擇下一步要抓取的網頁URL，并重復上述過程，直到達到保存URL的隊列為空為止。另外，所有被爬蟲抓取的網頁將會被系統存貯。    文章在分析網絡爬蟲的工作原理的基礎上，結合多線程技術，設計了這個網絡爬蟲程序。

關鍵字：搜索引擎，網絡爬蟲，電子商務
  

 The Topic-Specific Web Crawler of Oriented e-commerce website Design and Implementation

Abstract
     Web Crawler is a procedure of automatically downloading website pages, it downloads website pages from the World Wide Web for search engine, and works as an important component of search engine. Traditional Web Crawler starts from one or several of the initial URL of a website, and get some new URLs from the website pages, in the process of continuously downloading website html pages, it finds some new URLs and determine which URLs will be added into a queue, it works until the URL Queue is empty.
      The Web Crawler, which is designed by me, is to collect information on the e-commerce websites, so that users can find as much information as they concerned.
     The Web Crawler which downloads e-commerce websites, has a very complicated workflow, and needs doing an analysis for the website and filter links which are unrelated to e-commerce website, then keeps the useful links and places them into the URL queue. Then, under certain searching strategy, it would choose the next URL from the queue to download the website page, and repeat this process until the URL queue is empty. In addition, all the pages are stored on the local driver.
     Based on the analysis of the principle of the Web Crawler, and the multithreading technology, this article designs this Web Crawler procedure.
       
Key Words: Search engine, Web Crawler, E-commerce

目   錄
摘   要 I
Abstract II
目   錄 III
1 緒論 4
1.1 課題背景及意義 4
1.2 國內外研究現狀 2
1.3 爬蟲程序在電子商務的應用 3
1.4 本文所要完成的工作 4
2 網絡爬蟲 5
2.1 搜索引擎概述 5
2.1.1 通用搜索引擎概述 5
2.1.2 專業搜索引擎介紹 5
2.1.3 搜索引擎的性能指標 7
2.2 網絡爬蟲概述 9
2.2.1 網絡爬蟲簡介 9
2.2.2 網絡爬蟲工作原理 9
3 專業網絡爬蟲的設計 10
3.1 爬蟲設計原理 10
3.2 線程技術的應用 10
3.2.1 創建線程 10
3.2.2  線程間通信 11
3.3 網絡爬蟲結構分析 11
3.3.1 如何解析HTML 11
3.3.2 Spider程序結構 13
3.3.3 構造Spider程序 15
3.3.4 URL篩選策略 18
3.4 運行結果分析 18
結論 20
致謝 21
參考文獻 22