Python Requests 库使用指南

简介：Requests 是一个优雅而简单的 HTTP 库，专为人类设计。它让发送 HTTP/1.1 请求变得非常简单。

# 安装 pip install requests # 导入 import requests

# 基本 GET 请求 response = requests.get('https://api.example.com/data') # 带参数的 GET 请求 params = {'key1': 'value1', 'key2': 'value2'} response = requests.get('https://api.example.com/data', params=params)

# 基本 POST 请求（表单数据） data = {'key1': 'value1', 'key2': 'value2'} response = requests.post('https://api.example.com/data', data=data) # JSON 格式的 POST 请求 json_data = {'key1': 'value1', 'key2': 'value2'} response = requests.post('https://api.example.com/data', json=json_data)

requests.put('https://api.example.com/data', data=data) requests.delete('https://api.example.com/data') requests.patch('https://api.example.com/data', data=data) requests.head('https://api.example.com/data') requests.options('https://api.example.com/data')

data vs json vs params 的区别

• data: 放在请求体中，格式为表单数据 (key=value&key2=value2)
• json: 放在请求体中，格式为 JSON ({"key": "value"})
• params: 附加在 URL 后面，无论 GET 还是 POST 都适用 (url?key=value)

# 示例对比 import requests # 1. 使用 data (表单格式) requests.post('https://api.com/login', data={'username': 'admin', 'password': '123456'}) # 请求体: username=admin&password=123456 # Content-Type: application/x-www-form-urlencoded # 2. 使用 json (JSON格式) requests.post('https://api.com/login', json={'username': 'admin', 'password': '123456'}) # 请求体: {"username": "admin", "password": "123456"} # Content-Type: application/json # 3. 使用 params (URL参数) requests.post('https://api.com/login', params={'token': 'xyz123'}) # URL: https://api.com/login?token=xyz123 # 请求体: 空 # 4. 混合使用 requests.post('https://api.com/login', params={'version': 'v1'}, # URL: ?version=v1 json={'username': 'admin'}) # Body: {"username": "admin"}

response = requests.get('https://api.example.com/data') # 状态码 print(response.status_code) # 200, 404, 500 等 # 响应内容 print(response.text) # 字符串格式 print(response.json()) # JSON 格式（自动解析） print(response.content) # 字节格式 # 响应头 print(response.headers) # 检查请求是否成功 if response.status_code == 200: data = response.json() print(data) else: print(f"请求失败: {response.status_code}")

import requests from requests.exceptions import Timeout, ConnectionError, HTTPError try: response = requests.get('https://api.example.com/data', timeout=10) response.raise_for_status() # 如果状态码表示错误，抛出异常 data = response.json() print(data) except Timeout: print("请求超时") except ConnectionError: print("连接错误") except HTTPError as e: print(f"HTTP 错误: {e}") except Exception as e: print(f"其他错误: {e}")

# 标准 OAuth2.0 实现（参数在请求体中） token_params = { 'grant_type': 'authorization_code', 'client_id': 'your_client_id', 'client_secret': 'your_client_secret', 'code': 'authorization_code', 'redirect_uri': 'https://yourapp.com/callback' } response = requests.post('https://oauth.server.com/token', data=token_params, timeout=10) if response.status_code == 200: token_data = response.json() access_token = token_data['access_token']

# 创建资源 new_user = { 'username': 'john_doe', 'email': 'john@example.com', 'age': 30 } headers = { 'Authorization': 'Bearer your_access_token', 'Content-Type': 'application/json' } response = requests.post('https://api.example.com/users', json=new_user, headers=headers)

# 上传文件 files = { 'file': ('report.pdf', open('report.pdf', 'rb'), 'application/pdf') } response = requests.post('https://api.example.com/upload', files=files)

# 使用 Session 保持连接和 Cookie session = requests.Session() # 登录 login_data = {'username': 'admin', 'password': '123456'} session.post('https://api.example.com/login', data=login_data) # 后续请求会自动携带 Cookie response = session.get('https://api.example.com/profile') # 关闭会话 session.close()

headers = { 'User-Agent': 'MyApp/1.0', 'Accept': 'application/json', 'Authorization': 'Bearer token123' } response = requests.get('https://api.example.com/data', headers=headers)

proxies = { 'http': 'http://proxy.example.com:8080', 'https': 'https://proxy.example.com:8080' } response = requests.get('https://api.example.com/data', proxies=proxies)

# 大文件下载 response = requests.get('https://example.com/largefile.zip', stream=True) with open('largefile.zip', 'wb') as f: for chunk in response.iter_content(chunk_size=8192): f.write(chunk)

注意事项：

• 始终设置 timeout 参数，避免请求无限等待
• 生产环境中要妥善处理异常情况
• 敏感信息不要硬编码在代码中，使用环境变量或配置文件
• 对于频繁的请求，考虑使用 Session 来提高性能