Python API 第一次尝试

Question

我从 API 和 Python 开始。下面的代码可以正常工作。

import requests
import json

def jprint(obj):
    # create a formatted string of the Python JSON object
    text = json.dumps(obj, sort_keys=True, indent=4)
    print(text)

response = requests.get("http://api.open-notify.org/astros.json")
print(response.status_code)
print(response.json())
print()
jprint(response.json())

但是当我尝试做一些更可重用的事情以供以后使用时，我错过了一些东西......如何解决错误？

raise TypeError(f'Object of type {o.class.name} ' TypeError：DataFeed 类型的对象不是 JSON 可序列化的

感谢您的帮助。

import requests
import json

"""Open APIs From Space: https://www.dataquest.io/blog/python-api-tutorial/
"""

class DataFeed:

    base_url = "http://api.open-notify.org/"
    number_of_people_in_space = "astros.json"

    def __init__(self):
        pass

    def _build_url(self):
        url = f"{self.base_url}" \
              f"{self.number_of_people_in_space}"
        return url

    def get(self, url):
        response = requests.get(url)
        content = response.json()
        print(url)
        print(response.status_code)
        print(response.json())

    def get_data_feed(self):
        url = self._build_url()
        self.get(url)

    def jprint(obj):
        # create a formatted string of the Python JSON object
        text = json.dumps(obj, sort_keys=True, indent=4)
        print(text)

message = DataFeed()
message.get_data_feed()
message.jprint()

Answer 1

不要忘记传递给类方法的任何第一个参数总是引用自身self。

所以当你将obj, 传递给 json.dumps(obj, ...) 时，它会将DataFeed 的实例传递给json.dumps 函数。你想要的是通过response.json()。

class DataFeed:

    base_url = "http://api.open-notify.org/"
    number_of_people_in_space = "astros.json"

    def __init__(self):
        pass

    def _build_url(self):
        url = f"{self.base_url}" \
              f"{self.number_of_people_in_space}"
        return url

    def get(self, url):
        response = requests.get(url)
        self.content = response.json()  #changes made here
        print(url)
        print(response.status_code)
        print(response.json())

    def get_data_feed(self):
        url = self._build_url()
        self.get(url)

    def jprint(self): #changes made here

        # create a formatted string of the Python JSON object
        text = json.dumps(self.content, sort_keys=True, indent=4) #changes made here
        print(text)

message = DataFeed()
message.get_data_feed()
message.jprint()