Introduce a crawler framework that can replace Scrapy - feapder

1 Introduction

Hello everyone, I'm Ango!

As we all know, the most popular crawler framework for Python is Scrapy, which is mainly used to crawl website structural data

Today I recommend a simpler, lightweight, and powerful crawler framework: feapder

project address:

github.com/Boris-code/…

2. Introduction and Installation

Similar to Scrapy, feapder supports lightweight crawler, distributed crawler, batch crawler, crawler alarm mechanism and other functions

The three built-in crawlers are as follows:

  • AirSpider

    Lightweight crawlers, suitable for crawlers with simple scenarios and small amounts of data

  • Spider

    Distributed crawler, based on Redis, suitable for massive data, and supports functions such as breakpoint continuous crawling, automatic data storage and other functions

  • BatchSpider

    Distributed batch crawlers, mainly used for crawlers that require periodic collection

Before the actual combat, we install the corresponding dependency library in the virtual environment

# 安装依赖库
pip3 install feapder
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3. Let's fight

We use the simplest AirSpider to crawl some simple data

Target website: aHR0cHM6Ly90b3BodWIudG9kYXkvIA==

The detailed implementation steps are as follows (5 steps)

3-1 Create a crawler project

First, we use the "feapder create -p" command to create a crawler project

# 创建一个爬虫项目
feapder create -p tophub_demo
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3-2 Create a crawler AirSpider

Go to the spiders folder from the command line and use the "feapder create -s" command to create a crawler

cd spiders

# 创建一个轻量级爬虫
feapder create -s tophub_spider 1
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in

  • 1 is the default, which means to create a lightweight crawler AirSpider

  • 2 represents the creation of a distributed crawler Spider

  • 3 represents the creation of a distributed batch crawler BatchSpider

3-3 Configure database, create data table, create mapping item

Taking Mysql as an example, first we create a data table in the database

# 创建一张数据表
create table topic(    id         int auto_increment        primary key,    title      varchar(100)  null comment '文章标题',    auth       varchar(20)   null comment '作者',    like_count     int default 0 null comment '喜欢数',    collection int default 0 null comment '收藏数',    comment    int default 0 null comment '评论数');
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Then, open the settings.py file in the project root directory to configure the database connection information

# settings.py

MYSQL_IP = "localhost"
MYSQL_PORT = 3306
MYSQL_DB = "xag"
MYSQL_USER_NAME = "root"
MYSQL_USER_PASS = "root"
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Finally, create a mapping Item (optional)

Go to the items folder and use the "feapder create -i" command to create a file that maps to the database

PS: Since AirSpider does not support automatic data storage, this step is not necessary

3-4 Write crawler and data analysis

The first step is to initialize the database with "MysqlDB"

from feapder.db.mysqldb import MysqlDB

class TophubSpider(feapder.AirSpider):

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.db = MysqlDB()
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In the second step, in the start_requests method, specify the address of the main link to be crawled, and use the keyword "download_midware" to configure a random UA

import feapder
from fake_useragent import UserAgent

def start_requests(self):
    yield feapder.Request("https://tophub.today/", download_midware=self.download_midware)

def download_midware(self, request):
    # 随机UA
    # 依赖:pip3 install fake_useragent
    ua = UserAgent().random
    request.headers = {'User-Agent': ua}
    return request
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The third step is to crawl the title and link address of the home page

Use feapder's built-in method xpath to parse the data

def parse(self, request, response):
    # print(response.text)
    card_elements = response.xpath('//div[@class="cc-cd"]')

    # 过滤出对应的卡片元素【什么值得买】
    buy_good_element = [card_element for card_element in card_elements if
                        card_element.xpath('.//div[@class="cc-cd-is"]//span/text()').extract_first() == '什么值得买'][0]

    # 获取内部文章标题及地址
    a_elements = buy_good_element.xpath('.//div[@class="cc-cd-cb nano"]//a')

    for a_element in a_elements:
        # 标题和链接
        title = a_element.xpath('.//span[@class="t"]/text()').extract_first()
        href = a_element.xpath('.//@href').extract_first()

        # 再次下发新任务,并带上文章标题
        yield feapder.Request(href, download_midware=self.download_midware, callback=self.parser_detail_page,
                              title=title)
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The fourth step is to crawl the details page data

In the previous step, a new task is issued, and the callback function is specified through the keyword "callback", and finally the data analysis is performed on the details page in the parser_detail_page

def parser_detail_page(self, request, response):
    """
    解析文章详情数据
    :param request:
    :param response:
    :return:
    """
    title = request.title

    url = request.url

    # 解析文章详情页面,获取点赞、收藏、评论数目及作者名称
    author = response.xpath('//a[@class="author-title"]/text()').extract_first().strip()

    print("作者:", author, '文章标题:', title, "地址:", url)

    desc_elements = response.xpath('//span[@class="xilie"]/span')

    print("desc数目:", len(desc_elements))

    # 点赞
    like_count = int(re.findall('\d+', desc_elements[1].xpath('./text()').extract_first())[0])
    # 收藏
    collection_count = int(re.findall('\d+', desc_elements[2].xpath('./text()').extract_first())[0])
    # 评论
    comment_count = int(re.findall('\d+', desc_elements[3].xpath('./text()').extract_first())[0])

    print("点赞:", like_count, "收藏:", collection_count, "评论:", comment_count)
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3-5 Data storage

Use the database object instantiated above to execute SQL and insert data into the database.

# 插入数据库
sql = "INSERT INTO topic(title,auth,like_count,collection,comment) values('%s','%s','%s','%d','%d')" % (
title, author, like_count, collection_count, comment_count)

# 执行
self.db.execute(sql)
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4. Finally

This article talks about the simplest crawler AirSpider in feapder through a simple example

Regarding the use of advanced functions of feapder, I will explain in detail through a series of examples later.

I have uploaded all the code in the article to the background of the official account, and replied to the keyword "  airspider  " in the background to get the complete source code

If you think the article is not bad, please like  , share, and leave a message  , because this will be the strongest motivation for me to continue to output more high-quality articles!

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Origin juejin.im/post/6954573987187785735