蟒蛇:从couchdb端点获取npm包数据

时间:2019-07-03 18:06:33

标签: python npm npmjs

我想获取npm软件包元数据。我发现this端点为我提供了所需的所有元数据。

我制作了以下脚本来获取此数据。我的计划是选择一些特定的键并将该数据添加到某些数据库中(我也可以将其存储在json文件中,但是数据很大)。我制作了以下脚本来获取数据:

import requests
import json
import sys

db = 'https://replicate.npmjs.com';

r = requests.get('https://replicate.npmjs.com/_all_docs', headers={"include_docs" : "true"})

for line in r.iter_lines():
    # filter out keep-alive new lines
    if line:
        print(line)
        decoded_line = line.decode('utf-8')
        print(json.loads(decoded_line))

注意,我什至没有包含all-docs,但它会陷入无限循环。我认为这是因为数据巨大。

看看-https://replicate.npmjs.com/_all_docs

输出的开头

提供以下输出:

{"total_rows":1017703,"offset":0,"rows":[
{"id":"0","key":"0","value":{"rev":"1-5fbff37e48e1dd03ce6e7ffd17b98998"}},
{"id":"0-","key":"0-","value":{"rev":"1-420c8f16ec6584c7387b19ef401765a4"}},
{"id":"0----","key":"0----","value":{"rev":"1-55f4221814913f0e8f861b1aa42b02e4"}},
{"id":"0-1-project","key":"0-1-project","value":{"rev":"1-3cc19950252463c69a5e717d9f8f0f39"}},
{"id":"0-100","key":"0-100","value":{"rev":"1-c4f41a37883e1289f469d5de2a7b505a"}},
{"id":"0-24","key":"0-24","value":{"rev":"1-e595ec3444bc1039f10c062dd86912a2"}},
{"id":"0-60","key":"0-60","value":{"rev":"2-32c17752acfe363fa1be7dbd38212b0a"}},
{"id":"0-9","key":"0-9","value":{"rev":"1-898c1d89f7064e58f052ff492e94c753"}},
{"id":"0-_-0","key":"0-_-0","value":{"rev":"1-d47c142e9460c815c19c4ed3355d648d"}},
{"id":"0.","key":"0.","value":{"rev":"1-11c33605f2e3fd88b5416106fcdbb435"}},
{"id":"0.0","key":"0.0","value":{"rev":"1-5e541d4358c255cbcdba501f45a66e82"}},
{"id":"0.0.1","key":"0.0.1","value":{"rev":"1-ce856c27d0e16438a5849a97f8e9671d"}},
{"id":"0.0.168","key":"0.0.168","value":{"rev":"1-96ab3047e57ca1573405d0c89dd7f3f2"}},
{"id":"0.0.250","key":"0.0.250","value":{"rev":"1-c07ad0ffb7e2dc51bfeae2838b8d8bd6"}}, 

请注意,所有文档均从第二行开始(即,所有文档都是“行”键值的一部分)。现在,我的问题是如何仅获取“行”键的值(即所有文档)。我发现this存储库是出于类似的目的,但是由于我是JavaScript的初学者,所以无法使用/转换它。

2 个答案:

答案 0 :(得分:1)

如果stream=True的参数中没有get(),那么整个数据将被下载到内存中 之前,甚至循环遍历。

然后是一个问题,至少这些行本身不是有效的JSON。为此,您将需要像ijson这样的增量JSON解析器。 ijson想要一个类似对象的文件,而该文件很难从requests.Response获得,因此我将在这里使用Python标准库中的urllib

#!/usr/bin/env python3
from urllib.request import urlopen

import ijson


def main():
    with urlopen('https://replicate.npmjs.com/_all_docs') as json_file:
        for row in ijson.items(json_file, 'rows.item'):
            print(row)


if __name__ == '__main__':
    main()

答案 1 :(得分:0)

您是否有理由在遍历行之前不解码json?

您能尝试一下吗?

import requests
import json
import sys

db = 'https://replicate.npmjs.com';

r = requests.get('https://replicate.npmjs.com/_all_docs', headers={"include_docs" : "true"})

decoded_r = r.decode('utf-8')
data = json.loads(decoded_r)

for row in data.rows:
    print(row.key)