使用Python Office365客户端下载SharePoint文件时遇400/404错误

问题现象 #

使用Office 365 Python客户端通过用户凭证访问SharePoint，可以正常列出文件，但下载操作报错：

1. 使用完整文件URL调用File.open_binary时，返回400错误（无详细响应内容）
2. 改用站点相对路径写法时，返回404错误，响应提示文件不存在

报错代码示例 #

示例1：完整URL写法（报400） #

from office365.runtime.auth.authentication_context import AuthenticationContext,UserCredential
from office365.sharepoint.client_context import ClientContext
from office365.sharepoint.files.file import File
import logging

url = "https://xxxxxx.sharepoint.com/"
username= "xxxxxx@xxxxxx.org"
password= "xxxxxxxx"

ctx = ClientContext(url).with_user_credentials(username, password)

file_url = "https://xxxxxxx.sharepoint.com/sites/xxxxxxx/Shared Documents/Public/xxxxxx.pdf"
response = File.open_binary(ctx, file_url)

print(response)
with open("./xxxxxx.pdf", "wb") as local_file:
    local_file.write(response.content)

示例2：相对路径写法（报404） #

context = ClientContext(url).with_user_credentials(username, password)

response = File.open_binary(context, '/'.join(['/sites/xxxxx/Shared Documents/Public', 
                                           'xxxxx.pdf']))

print(response)

404错误响应内容 #

b'{"error":{"code":"-2130575338, Microsoft.SharePoint.SPException","message":{"lang":"en-US","value":"The file /sites/xxxx/Shared Documents/Public/xxxxxx.pdf does not exist."}}}'

解决方法 #

1. 修正ClientContext的站点指向 #

当前代码中ClientContext初始化用的是SharePoint根站点URL，但目标文件位于子站点/sites/xxxxxxx/下，必须将上下文指向子站点：

site_url = "https://xxxxxx.sharepoint.com/sites/xxxxxxx/"
ctx = ClientContext(site_url).with_user_credentials(username, password)

2. 使用正确的相对路径 #

当上下文指向子站点后，文件路径需使用相对于该子站点的路径，无需包含/sites/xxxxxxx/前缀：

file_relative_path = "Shared Documents/Public/xxxxxx.pdf"
response = File.open_binary(ctx, file_relative_path)

3. 前置验证文件状态（可选） #

可以先通过API验证文件是否存在、权限是否正常，避免直接下载时报错：

try:
    file = ctx.web.get_file_by_server_relative_url(file_relative_path).get().execute_query()
    print(f"文件存在：{file.name}")
except Exception as e:
    print(f"验证失败：{e}")

完整可运行代码 #

from office365.sharepoint.client_context import ClientContext
from office365.sharepoint.files.file import File
from office365.runtime.auth.user_credential import UserCredential

# 子站点完整URL
site_url = "https://xxxxxx.sharepoint.com/sites/xxxxxxx/"
username = "xxxxxx@xxxxxx.org"
password = "xxxxxxxx"

# 初始化上下文
ctx = ClientContext(site_url).with_credentials(UserCredential(username, password))

# 文件相对于子站点的路径
file_relative_path = "Shared Documents/Public/xxxxxx.pdf"

# 验证文件存在性
try:
    file = ctx.web.get_file_by_server_relative_url(file_relative_path).get().execute_query()
except Exception as e:
    print(f"文件不存在或权限不足：{str(e)}")
    exit()

# 下载文件
response = File.open_binary(ctx, file_relative_path)
with open("./xxxxxx.pdf", "wb") as local_file:
    local_file.write(response.content)
print("文件下载成功")

内容的提问来源于stack exchange，提问作者Axen_Rangs