Python爬虫 错误：json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0)

Question

一、问题
练习协程，使用aiohttp.ClientSession().get(url).json()报错，代码如下：

async def aiodownload(bid, cid, title):
    # 异步任务
    data = {
        'book_id': bid,
        'cid': f'{bid}|{cid}',
        'need_bookinfo': 1
    }
    data = json.dumps(data)
    header = {
        'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/98.0.4758.102 Safari/537.36'
    }
    base_url = f'http://dushu.baidu.com/api/pc/getChapterContent/?data={data}'
    async with aiohttp.ClientSession() as session:
        async with session.get(base_url, headers=header) as resp:
            # ！！出错地方
            dic = await resp.json()  #content_type=None
            async with aiofiles.open('.novel/' + title, 'w', newline='', encoding='utf-8') as f:
                await f.write(dic['data']['novel']['content'])
    print('done!')

这段代码是跟着B站的课写的，一样的代码，up跑成功了，俺不成功。
不用协程单独拿出来访问是没有问题的，如下，一加上await就出错，json不成功

# 这样是正常的
bid = '4306063500'
cid = '1569782244'
data = {
         'book_id': bid,
         'cid': f'{bid}|{cid}',
         'need_bookinfo': 1
     }
data = json.dumps(data)
url1 = f'http://dushu.baidu.com/api/pc/getChapterContent?data={data}'
resp = requests.get(url1)
    # print(resp.json())
dic = resp.json()
print(dic['data']['novel']['content'])
resp.close()

二、报错

Task exception was never retrieved
in json raise ContentTypeError(
aiohttp.client_exceptions.ContentTypeError: 0, message='Attempt to decode JSON with unexpected mimetype: text/html; charset=utf-8', 

Process finished with exit code 0

三、尝试解决（全是在网上搜的解决办法
json()里指定类型，dic = await resp.json(content_type=None, encoding='utf-8)
还是报错：json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0)，这个错误没找到解决办法

刚开始学，不知如何下手解决，礼貌求解！

Answer 1

async+await方法的url多了个斜杠，去掉就行了。要不多的那个斜杠接口出错返回的是html代码了，调用json()出错了，内容不是json字符串

测试代码如下

import json
import aiohttp
import asyncio
async def aiodownload(bid, cid, title):
    # 异步任务
    data = {
        'book_id': bid,
        'cid': f'{bid}|{cid}',
        'need_bookinfo': 1
    }
    data = json.dumps(data)
    header = {
        'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/98.0.4758.102 Safari/537.36'
    }
    base_url = f'http://dushu.baidu.com/api/pc/getChapterContent?data={data}'
    
    async with aiohttp.ClientSession() as session:
        async with session.get(base_url, headers=header) as resp:
            # ！！出错地方
            dic = await resp.json()  #content_type=None
            #async with aiofiles.open('.novel/' + title, 'w', newline='', encoding='utf-8') as f:
                #await f.write(dic['data']['novel']['content'])
    print(dic)

loop = asyncio.get_event_loop()
loop.run_until_complete(aiodownload('4306063500','1569782244','xxx'))