如何在Python中使用google.auth.transport.requests进行身份验证和请求

在Python中使用google.auth.transport.requests进行身份验证和请求，需要进行以下步骤：

1. 安装google-auth库和google-auth-httplib2库，可通过以下命令进行安装：

pip install google-auth google-auth-httplib2

2. 导入必要的模块：

import google.auth
from google.auth.transport.requests import Request
from google.auth.transport.requests import AuthorizedSession

3. 创建Google授权会话：

# 如果之前已经授权，则从缓存中获取凭据
credentials, project_id = google.auth.default(
    scopes=["https://www.googleapis.com/auth/cloud-platform"]
)
# 如果没有凭据或者凭据过期，则通过REFRESH_TOKEN进行重新授权
if not credentials or not credentials.valid:
    if credentials and credentials.expired and credentials.refresh_token:
        credentials.refresh(Request())
    else:
        flow = google.auth.OAuth2WebServerFlow(
            client_id="CLIENT_ID",
            client_secret="CLIENT_SECRET",
            redirect_uri="REDIRECT_URI",
            scope="https://www.googleapis.com/auth/cloud-platform",
        )
        # 生成授权URL
        auth_url = flow.step1_get_authorize_url()
        print("Please go to this URL: {}".format(auth_url))
        # 获取用户授权的授权码
        code = input("Enter the authorization code: ")
        # 通过授权码获取凭据
        credentials = flow.step2_exchange(code)
    # 保存凭据至缓存
    google.auth.default(credentials, project_id)

4. 创建AuthorizedSession对象，以便发送授权请求：

session = AuthorizedSession(credentials)

5. 发送请求，并获取返回结果：

# GET请求
response = session.get("https://api.example.com/get_data")
data = response.json()

# POST请求
payload = {"key": "value"}
response = session.post("https://api.example.com/post_data", json=payload)
data = response.json()

完整的使用示例代码如下所示：

import google.auth
from google.auth.transport.requests import Request
from google.auth.transport.requests import AuthorizedSession

# 如果之前已经授权，则从缓存中获取凭据
credentials, project_id = google.auth.default(
    scopes=["https://www.googleapis.com/auth/cloud-platform"]
)
# 如果没有凭据或者凭据过期，则通过REFRESH_TOKEN进行重新授权
if not credentials or not credentials.valid:
    if credentials and credentials.expired and credentials.refresh_token:
        credentials.refresh(Request())
    else:
        flow = google.auth.OAuth2WebServerFlow(
            client_id="CLIENT_ID",
            client_secret="CLIENT_SECRET",
            redirect_uri="REDIRECT_URI",
            scope="https://www.googleapis.com/auth/cloud-platform",
        )
        # 生成授权URL
        auth_url = flow.step1_get_authorize_url()
        print("Please go to this URL: {}".format(auth_url))
        # 获取用户授权的授权码
        code = input("Enter the authorization code: ")
        # 通过授权码获取凭据
        credentials = flow.step2_exchange(code)
    # 保存凭据至缓存
    google.auth.default(credentials, project_id)

# 创建AuthorizedSession对象
session = AuthorizedSession(credentials)

# 发送GET请求
response = session.get("https://api.example.com/get_data")
data = response.json()
print(data)

# 发送POST请求
payload = {"key": "value"}
response = session.post("https://api.example.com/post_data", json=payload)
data = response.json()
print(data)

通过以上步骤，我们可以在Python中使用google.auth.transport.requests进行身份验证和发送授权请求。