复杂的python3 csv刮板 [英] Complex python3 csv scraper

问题描述

当我从行[0] 中连续提取数据时，下面的代码可以很好地工作.我想知道如何调整它以从多行中提取数据?

I've got the code below working great when pulling data from a row, in my case row[0]. I'm wondering how to tweak it to pull data from multiple rows?

此外，我希望能够指定用于特定列的 divTag类(请参见下面的代码).

Also, I would love to be able to specify which divTag class (see the code below) to use for a specific column.

类似于用于行[1,2] 的用途:

divTag = soup.find("div", {"class": "productsPicture"})

，行[4,5] 使用:

divTag = soup.find("div", {"class": "product_content"})

如果这对你们有意义.

If that make sense to you guys.

from bs4 import BeautifulSoup
import requests
import csv

with open('urls.csv', 'r') as csvFile, open('results.csv', 'w', newline='') as results:
reader = csv.reader(csvFile, delimiter=';')
writer = csv.writer(results)

for row in reader:
    # get the url
    url = row[0]
    print(url)

    # fetch content from server

    try:
        html = requests.get(url).content
    except requests.exceptions.ConnectionError as e:
        writer.writerow([url, '', 'bad url'])
        continue

    # soup fetched content
    soup = BeautifulSoup(html, 'html.parser')

    divTag = soup.find("div", {"class": "productsPicture"})

    if divTag:
        # Return all 'a' tags that contain an href
        for a in divTag.find_all("a", href=True):
            url_sub = a['href']

            # Test that link is valid
            try:
                r = requests.get(url_sub)
                writer.writerow([url, url_sub, 'ok'])
            except requests.exceptions.ConnectionError as e:
                writer.writerow([url, url_sub, 'bad link'])
    else:
        writer.writerow([url, '', 'no results'])

urls.csv示例:

https://www.tennis-point.com/index.php?stoken=737F2976&lang=1&cl=search&searchparam=E705Y-0193;
https://www.tennis-point.com/index.php?stoken=737F2976&lang=1&cl=search&searchparam=E703Y-0193;
https://www.tennis-point.com/index.php?stoken=737F2976&lang=1&cl=search&searchparam=E702Y-4589;
https://www.tennis-point.com/index.php?stoken=737F2976&lang=1&cl=search&searchparam=E706Y-9093;

要搜索的示例类:

推荐答案

要添加每列的find参数，您可以创建一个字典，将索引号映射到所需的find参数，如下所示:

To add a per column find parameter, you could create a dictionary mapping the index number into the required find parameters as follows:

from bs4 import BeautifulSoup
import requests
import csv

class_1 = {"class": "productsPicture"}
class_2 = {"class": "product_content"}
class_3 = {"class": "id-fix"}

# map a column number to the required find parameters
class_to_find = {
    0 : class_3,    # Not defined in question
    1 : class_1,    
    2 : class_1,
    3 : class_3,    # Not defined in question
    4 : class_2, 
    5 : class_2}

with open('urls.csv', 'r') as csvFile, open('results.csv', 'w', newline='') as results:
    reader = csv.reader(csvFile)
    writer = csv.writer(results)

    for row in reader:
        # get the url

        output_row = []

        for index, url in enumerate(row):
            url = url.strip()

            # Skip any empty URLs
            if len(url):
                #print('col: {}\nurl: {}\nclass: {}\n\n'.format(index, url, class_to_find[index]))

                # fetch content from server

                try:
                    html = requests.get(url).content
                except requests.exceptions.ConnectionError as e:
                    output_row.extend([url, '', 'bad url'])
                    continue
                except requests.exceptions.MissingSchema as e:
                    output_row.extend([url, '', 'missing http...'])
                    continue

                # soup fetched content
                soup = BeautifulSoup(html, 'html.parser')


                divTag = soup.find("div", class_to_find[index])

                if divTag:
                    # Return all 'a' tags that contain an href
                    for a in divTag.find_all("a", href=True):
                        url_sub = a['href']

                        # Test that link is valid
                        try:
                            r = requests.get(url_sub)
                            output_row.extend([url, url_sub, 'ok'])
                        except requests.exceptions.ConnectionError as e:
                            output_row.extend([url, url_sub, 'bad link'])
                else:
                    output_row.extend([url, '', 'no results'])      

        writer.writerow(output_row)

使用了 enumerate() 函数返回遍历列表的计数器.因此，第一个URL的index将是0，下一个URL的1将.然后可以将其与class_to_find词典一起使用，以获取搜索所需的参数.

The enumerate() function is used to return a counter whist iterating over a list. So index will be 0 for the first URL, and 1 for the next. This can then be used with the class_to_find dictionary to get the required parameters to search on.

每个URL都会创建3列，分别是URL，成功的子URL和结果.如果不需要，可以将其删除.

Each URL results in 3 columns being created, the url, the sub-url if successful and the result. These can be removed if not needed.

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