如何制作一个解析名称为“patch”或“fix？”的链接的webcrawler。

Question

我正在尝试为Debian GSoC项目的应用程序任务编程，我已经能够解析从Internet下载的文本文件，但我很难从页面上的链接下载补丁通过抓取页面，尤其是出现的第一页：来自sourceware.org的BugZilla站点。

这是我试过的代码：

#!/usr/bin/env python3 This program uses Python 3, don't use with 2.
import requests
from bs4 import BeautifulSoup
import re
import os


PAGES_CAH = ["https://sourceware.org/bugzilla/show_bug.cgi?id=23685", "https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=f055032e4e922f1e1a5e11026c7c2669fa2a7d19", "https://github.com/golang/net/commit/4b62a64f59f73840b9ab79204c94fee61cd1ba2c", "http://www.ca.tcpdump.org/cve/0002-test-case-files-for-CVE-2015-2153-2154-2155.patch" ]
patches = []


def searchy(pages):
    for link in pages:
        global patches
        if "github.com" in link and "commit" in link: # detect that in each page that it's from GitHub
            if 'patch' not in link: # detect if it's a patch page or not
                link = link + '.patch' # add .patch to link if the patch link lacks it
            request = requests.get(link) # connect to page
            patches.append(request.text) # download patch to patches variable
        elif ".patch" in link: # any other page with ".patach" in the end is downloaded like GitHub patches by default
            request = requests.get(link) # connect to page
            patches.append(request) #downmload patch to patches variable
        else:
            request = requests.get(link) # connect to page
            soup = BeautifulSoup(request.text, "lxml") # turn the page into something parsable
            if "sourceware.org/git" in link: # if it's from sourceware.org's git:
                patch_link = soup.find_all('a', string="patch") # find all patch links
                patch_request = requests.get(patch_link[0]) # connect to patch link
                patches.append(patch_request.text) # download patch
            elif "sourceware.org/bugzilla" in link: # if it's from sourceware's bugzilla
                patch_link_possibilities = soup.find('a', id="attachment_table") # find all links from the attachment table
                local_patches_links = patch_link_possibilities.find_all(string="patch") # find all links with the "patch" name
                local_fixes_links = patch_link_possibilities.find_all(string="fix") # find all links with the "fix" name
                for lolpatch in local_patches_links: # for each local patch in the local patch links list
                    patch_request = requests.get(lolpatch) # connect to page
                    patches.append(patch_request.text) #download patch
                for fix in local_fixes_links: # for each fix in the local fix links list
                    patch_request = requests.get(fix) # connect to page
                    patches.append(patch_request.text) #download patch
searchy(PAGES_CAH)
print(patches)

Answer 1

你可以尝试添加:contains伪类选择器来查找链接文本中的patch。需要BeautifulSoup 4.7.1

import requests
from bs4 import BeautifulSoup
url = 'https://sourceware.org/bugzilla/show_bug.cgi?id=23685'
r = requests.get(url)
soup = BeautifulSoup(r.content, 'lxml')

links = [item['href'] for item in soup.select('a:contains(patch)')]
print(links)

您可以使用css或语法扩展：

links = [item['href'] for item in soup.select('a:contains(patch), a:contains(fix)')]