一文掌握Python中的request库（一文掌握python中的request库有哪些）

liuian 2025-03-20 16:25 40 浏览

为什么使用 requests 模块？
在深入研究细节之前，重要的是要了解为什么 Requests 模块比 urllib 等替代方案更受欢迎：

单纯：Requests 模块具有更直接的 API，需要更少的代码行来有效执行 HTTP 请求。
会话功能：它支持请求之间的持久会话，这对于涉及同一服务器多个事务的任务至关重要。
表单处理：通过其直观的方法，提交表单数据变得简单。
JSON 响应处理：该库允许轻松检索和管理 JSON 数据，JSON 数据是 Web 数据交换的常用格式。
异常处理：它会自动为错误状态代码引发异常，从而促进更好的错误管理和更顺畅的调试过程。

安装request模块

如果你还没有安装 requests 模块，你可以使用 pip 轻松完成：

pip install requests

基本用法

要开始使用 requests 模块，您需要导入它，然后您可以使用其函数发送各种类型的 HTTP 请求。

import requests

发送 GET 请求

以下是发送简单的 GET 请求以从服务器获取数据的方法：

import requests

# The URL to which the GET request will be sent.
url = 'https://api.example.com/data'

# Sending a GET request to the specified URL.
# The 'requests.get' function makes an HTTP GET request to the provided URL and stores the response in the 'response' variable.
response = requests.get(url)

# Printing the text content of the response.
# 'response.text' contains the body of the response from the server, typically in string format.
# This is useful for checking what data the server returned in response to the GET request.
print(response.text)

检查响应

发送请求后，检查响应至关重要：

# Check the HTTP status code of the response.
if response.status_code == 200:
    # If the status code is 200, it indicates that the request was successful.
    print('The request was successful!')
else:
    # If the status code is not 200, the request failed.
    # Print the status code to help diagnose the issue.
    print('The request failed with status code:', response.status_code)

GET 请求中的查询参数

如果需要使用 GET 请求发送查询参数：

# A dictionary containing query parameters for an HTTP GET request.
# These parameters will be appended to the URL as query strings.
params = {
    'key1': 'value1',
    'key2': 'value2'
}

# Sending a GET request to the specified URL. The 'params' dictionary is converted into query parameters.
# The Requests library automatically encodes these parameters and appends them to the URL.
response = requests.get(url, params=params)

# Printing the final URL after the query parameters have been appended.
# This is useful for debugging to verify that the URL has been constructed correctly.
print(response.url)  # This will show the URL with the appended query parameters.

POST 请求

向服务器发送数据通常是使用 POST 请求完成的。以下是对请求执行此操作的方法：

import requests 

# A dictionary containing the login credentials, typically a username and password.
data = {
    'username': 'john',
    'password': 'secret'
}

# Sending a POST request to the login endpoint of the API. 
# The 'data' dictionary is passed as form-encoded data to the server.
response = requests.post('https://api.example.com/login', data=data)

# Printing the text of the response from the server, which might include details like login status or tokens.
print(response.text)

# A dictionary representing the data of a new article, including its title, content and associated tags.
json_data = {
    'title': 'New Article',
    'content': 'This is a new article',
    'tags': ['python', 'requests']
}

# Sending a POST request to create a new article on the API.
# The 'json_data' dictionary is passed as JSON. The Requests library automatically sets the appropriate headers.
response = requests.post('https://api.example.com/articles', json=json_data)

# Printing the text of the response from the server, which could be details of the newly created article or an error message.
print(response.text)

处理响应内容

了解如何处理不同类型的响应内容至关重要：

# Printing the text content of the response.
# 'response.text' contains the raw string response received from the server.
print(response.text)

# Parsing the JSON response.
# 'response.json()' converts the JSON formatted string in the response to a Python dictionary.
# This method is convenient for handling JSON data, which is common in REST APIs.
data = response.json()

# Printing the converted Python dictionary.
# This displays the JSON data structured as a dictionary, making it easier to access and manipulate specific data fields.
print(data)