requests 是一个用于 HTTP 请求的简单且强大的 Python 库，以下是 requests 常用操作示例。

1. 安装 requests

bash
pip install requests

2. 导入 requests 模块

python
import requests

---

常用请求操作

GET 请求

python
response = requests.get("https://api.example.com/data")
print(response.status_code)  # 状态码
print(response.json())       # 获取 JSON 格式响应数据
print(response.text)         # 获取文本格式响应数据

POST 请求

python
payload = {"key": "value"}
response = requests.post("https://api.example.com/data", json=payload)
print(response.json())

其他 HTTP 方法

python
# PUT 请求
response = requests.put("https://api.example.com/data", json={"update": "value"})

# DELETE 请求
response = requests.delete("https://api.example.com/data")

---

设置请求参数、头部和超时

URL 参数

python
params = {"query": "test"}
response = requests.get("https://api.example.com/data", params=params)
print(response.url)  # 完整的请求 URL

自定义请求头

python
headers = {"Authorization": "Bearer token"}
response = requests.get("https://api.example.com/data", headers=headers)

超时设置

python
response = requests.get("https://api.example.com/data", timeout=10)

---

上传文件

python
files = {"file": ("filename.txt", open("filename.txt", "rb"), "text/plain")}
response = requests.post("https://api.example.com/upload", files=files)
print(response.status_code)

---

会话管理

使用 requests.Session() 进行会话管理，可以在同一会话中共享 cookie 和 headers。

python
with requests.Session() as session:
    session.headers.update({"Authorization": "Bearer token"})
    response = session.get("https://api.example.com/data")
    print(response.json())

---

常见配置选项

JSON 数据

• 可以直接发送和解析 JSON 数据：

python
response = requests.post("https://api.example.com/data", json={"key": "value"})
print(response.json())  # 自动解析 JSON 响应

重试机制

虽然 requests 没有内置重试机制，但可以借助 urllib3 提供的 Retry 类：

python
from requests.adapters import HTTPAdapter
from requests.packages.urllib3.util.retry import Retry

session = requests.Session()
retry = Retry(connect=3, backoff_factor=0.5)
adapter = HTTPAdapter(max_retries=retry)
session.mount("http://", adapter)
session.mount("https://", adapter)

response = session.get("https://api.example.com")

---

获取响应内容

获取响应状态码和内容

python
print(response.status_code)  # 获取状态码
print(response.text)         # 获取文本内容
print(response.content)      # 获取二进制内容
print(response.json())       # 解析 JSON 响应

获取响应头

python
print(response.headers)      # 所有响应头
print(response.headers["Content-Type"])  # 特定响应头

---

代理设置

python
proxies = {
    "http": "http://proxyserver:port",
    "https": "https://proxyserver:port",
}
response = requests.get("https://api.example.com", proxies=proxies)

---

Cookie 管理

设置和获取 Cookie

python
# 设置请求中的 Cookie
cookies = {"session_id": "123456"}
response = requests.get("https://api.example.com", cookies=cookies)

# 获取响应中的 Cookie
print(response.cookies)

---

下载文件

python
url = "https://example.com/file.zip"
response = requests.get(url, stream=True)
with open("file.zip", "wb") as file:
    for chunk in response.iter_content(chunk_size=1024):
        file.write(chunk)

---

SSL 证书验证

禁用 SSL 证书验证（不推荐）

python
response = requests.get("https://example.com", verify=False)

自定义证书路径

python
response = requests.get("https://example.com", verify="/path/to/cert.pem")