Python爬蟲入門教程 33-100 《海王》評論資料抓取 scrapy

1. 海王評論資料爬取前分析

海王上映了，然後口碑炸了，對我們來說，多了一個可爬可分析的電影，美哉~

摘錄一個評論

零點場剛看完，溫導的電影一直很不錯，無論是速7，電鋸驚魂還是招魂都很棒。打鬥和音效方面沒話說非常棒，特別震撼。總之，DC扳回一分（￣▽￣）。比正義聯盟好的不止一點半點（我個人感覺）。還有艾梅伯希爾德是真的漂亮，溫導選的人都很棒。
真的第一次看到這麼牛逼的電影 轉場特效都吊炸天

2. 海王案例開始爬取資料

資料爬取的依舊是貓眼的評論，這部分內容我們們用把牛刀，scrapy爬取，一般情況下，用一下requests就好了

抓取地址

http://m.maoyan.com/mmdb/comments/movie/249342.json?_v_=yes&offset=15&startTime=2018-12-11%2009%3A58%3A43

關鍵引數

url:http://m.maoyan.com/mmdb/comments/movie/249342.json
offset:15
startTime:起始時間

scrapy 爬取貓眼程式碼特別簡單，我分開幾個py檔案即可。

Haiwang.py

import scrapy
import json
from haiwang.items import HaiwangItem

class HaiwangSpider(scrapy.Spider):
    name = `Haiwang`
    allowed_domains = [`m.maoyan.com`]
    start_urls = [`http://m.maoyan.com/mmdb/comments/movie/249342.json?_v_=yes&offset=0&startTime=0`]

    def parse(self, response):
        print(response.url)
        body_data = response.body_as_unicode()

        js_data = json.loads(body_data)
        item = HaiwangItem()
        for info in js_data["cmts"]:

            item["nickName"] = info["nickName"]
            item["cityName"] = info["cityName"] if "cityName" in info else ""
            item["content"] = info["content"]
            item["score"] = info["score"]
            item["startTime"] = info["startTime"]
            item["approve"] = info["approve"]
            item["reply"] = info["reply"]
            item["avatarurl"] = info["avatarurl"]

            yield item

        yield scrapy.Request("http://m.maoyan.com/mmdb/comments/movie/249342.json?_v_=yes&offset=0&startTime={}".format(item["startTime"]),callback=self.parse)

setting.py

設定需要配置headers

DEFAULT_REQUEST_HEADERS = {
    "Referer":"http://m.maoyan.com/movie/249342/comments?_v_=yes",
    "User-Agent":"Mozilla/5.0 Chrome/63.0.3239.26 Mobile Safari/537.36",
    "X-Requested-With":"superagent"
}

需要配置一些抓取條件

# Obey robots.txt rules
ROBOTSTXT_OBEY = False
# See also autothrottle settings and docs
DOWNLOAD_DELAY = 1
# Disable cookies (enabled by default)
COOKIES_ENABLED = False

開啟管道

# Configure item pipelines
# See https://doc.scrapy.org/en/latest/topics/item-pipeline.html
ITEM_PIPELINES = {
   `haiwang.pipelines.HaiwangPipeline`: 300,
}

items.py
獲取你想要的資料

import scrapy


class HaiwangItem(scrapy.Item):
    # define the fields for your item here like:
    # name = scrapy.Field()
    nickName = scrapy.Field()
    cityName = scrapy.Field()
    content = scrapy.Field()
    score = scrapy.Field()
    startTime = scrapy.Field()
    approve = scrapy.Field()
    reply =scrapy.Field()
    avatarurl = scrapy.Field()

pipelines.py
儲存資料，資料儲存到csv檔案中

import os
import csv


class HaiwangPipeline(object):
    def __init__(self):
        store_file = os.path.dirname(__file__) + `/spiders/haiwang.csv`
        self.file = open(store_file, "a+", newline="", encoding="utf-8")
        self.writer = csv.writer(self.file)

    def process_item(self, item, spider):
        try:
            self.writer.writerow((
                item["nickName"],
                item["cityName"],
                item["content"],
                item["approve"],
                item["reply"],
                item["startTime"],
                item["avatarurl"],
                item["score"]
            ))

        except Exception as e:
            print(e.args)

        def close_spider(self, spider):
            self.file.close()

begin.py
編寫執行指令碼

from scrapy import cmdline
cmdline.execute(("scrapy crawl Haiwang").split())

走起，搞定，等著資料來到，就可以了