爬虫实例之爬取今日头条组图

试了一下爬取今日头条的组图。

首先是进入输入关键词后的索引页，使用chrom的开发者工具可以看到这是一个get请求，且包含一些数据，于是在这一步应该构造这个get请求，请求成功则会返回一个json数据。

def get_page_index(offset,keyword):
    data = {
            'offset':offset,
            'format':'json',
            'keyword':keyword,
            'autoload':'true',
            'count':'20',
            'cur_tab':3    
            }

    url = 'https://www.toutiao.com/search_content/?' + urlencode(data)

    try:
        response = requests.get(url)
        if response.status_code == 200:
            return response.text
        else:
            return None

    except RequestException:
        print("请求索引页失败")
        return None

对于上一步返回的数据进行解析，取出需要的article_url字段

def parse_page_index(html):
    data = json.loads(html)
    if data and 'data' in data.keys():
        for item in data.get('data'):
            yield item.get('article_url')

对每个组图的url进行请求：

def get_detail_page(url):
    try:
        response = requests.get(url)
        if response.status_code == 200:
            return response.text
        return None
    except RequestException:
        print("请求详情页面出错")
        return None

进行解析：

def parse_detail_page(html,url):
    pattern = re.compile('BASE_DATA.galleryInfo = (.*?);',re.S)
    result = re.search(pattern,html)
    data = result.group(1)

    pattern_title = re.compile('title:(.*?),',re.S)
    #print(result)
    result2 = re.search(pattern_title,data)
    #print(data)
    title = result2.group(1)

    pattern_image = re.compile('gallery: JSON.parse("(.*?)")')

    result3 = re.search(pattern_image,data)
    #print(result3.group(1))
    jsonStr = re.sub(r'\{1,2}', '',result3.group(1))
    #print(jsonStr)


    if result3:

        data_image = json.loads(jsonStr)

        if data_image and 'sub_images' in data_image.keys():
            sub_images = data_image.get('sub_images')
            images = [item.get('url') for item in sub_images]
            for image in images:
                download_image(image)
            return {"title":title,
                    "url":url,
                    "images":images}

对于解析出的每个图片信息保存至MongoDB：

def save_to_mongo(result):
    if db[MONGO_TABLE].insert(result):
        print("存储到MongoDB成功")
        return True
    return False


def download_image(url):
    try:
        response = requests.get(url)
        if response.status_code == 200:
            save_image(response.content)
        return None
    except RequestException:
        print("下载图片出错")
        return None

将图片保存至本地：

def save_image(content):
    file_path = '{0}/{1}.{2}'.format(os.getcwd(),md5(content).hexdigest(),'jpg')
    if not os.path.exists(file_path):
        with open(file_path,'wb') as f:
            f.write(content)
            f.close()

一部分保存下来的图片：

！！！！

附上完整源码