Question

我有存储桶 URL、名称和文件列表对象键，需要下载文件。

我尝试了什么：

import boto3
import botocore

BUCKET_NAME = 'my-bucket' 
KEY = 'my_file' 

s3 = boto3.resource('s3')

try:
    s3.Bucket(BUCKET_NAME).download_file(KEY, 'my_local_file')
except botocore.exceptions.ClientError as e:
    if e.response['Error']['Code'] == "404":
        print("The object does not exist.")
    else:
        raise

并发现错误：

Traceback (most recent call last):
  File "D:\me\work\Mackpaw Data Engeneering test tsk\main.py", line 10, in <module>
    s3.Bucket(BUCKET_NAME).download_file(KEY, 'data.json')
  File "C:\Users\Katherine\AppData\Local\Programs\Python\Python39\lib\site-packages\boto3\s3\inject.py", line 244, in bucket_download_file
    return self.meta.client.download_file(
  File "C:\Users\Katherine\AppData\Local\Programs\Python\Python39\lib\site-packages\boto3\s3\inject.py", line 170, in download_file
    return transfer.download_file(
  File "C:\Users\Katherine\AppData\Local\Programs\Python\Python39\lib\site-packages\boto3\s3\transfer.py", line 307, in download_file
    future.result()
  File "C:\Users\Katherine\AppData\Local\Programs\Python\Python39\lib\site-packages\s3transfer\futures.py", line 106, in result
    return self._coordinator.result()
  File "C:\Users\Katherine\AppData\Local\Programs\Python\Python39\lib\site-packages\s3transfer\futures.py", line 265, in result
    raise self._exception
  File "C:\Users\Katherine\AppData\Local\Programs\Python\Python39\lib\site-packages\s3transfer\tasks.py", line 255, in _main
    self._submit(transfer_future=transfer_future, **kwargs)
  File "C:\Users\Katherine\AppData\Local\Programs\Python\Python39\lib\site-packages\s3transfer\download.py", line 340, in _submit
    response = client.head_object(
  File "C:\Users\Katherine\AppData\Local\Programs\Python\Python39\lib\site-packages\botocore\client.py", line 357, in _api_call
    return self._make_api_call(operation_name, kwargs)
  File "C:\Users\Katherine\AppData\Local\Programs\Python\Python39\lib\site-packages\botocore\client.py", line 662, in _make_api_call
    http, parsed_response = self._make_request(
  File "C:\Users\Katherine\AppData\Local\Programs\Python\Python39\lib\site-packages\botocore\client.py", line 682, in _make_request
    return self._endpoint.make_request(operation_model, request_dict)
  File "C:\Users\Katherine\AppData\Local\Programs\Python\Python39\lib\site-packages\botocore\endpoint.py", line 102, in make_request
    return self._send_request(request_dict, operation_model)
  File "C:\Users\Katherine\AppData\Local\Programs\Python\Python39\lib\site-packages\botocore\endpoint.py", line 132, in _send_request
    request = self.create_request(request_dict, operation_model)
  File "C:\Users\Katherine\AppData\Local\Programs\Python\Python39\lib\site-packages\botocore\endpoint.py", line 115, in create_request
    self._event_emitter.emit(event_name, request=request,
  File "C:\Users\Katherine\AppData\Local\Programs\Python\Python39\lib\site-packages\botocore\hooks.py", line 356, in emit
    return self._emitter.emit(aliased_event_name, **kwargs)
  File "C:\Users\Katherine\AppData\Local\Programs\Python\Python39\lib\site-packages\botocore\hooks.py", line 228, in emit
    return self._emit(event_name, kwargs)
  File "C:\Users\Katherine\AppData\Local\Programs\Python\Python39\lib\site-packages\botocore\hooks.py", line 211, in _emit
    response = handler(**kwargs)
  File "C:\Users\Katherine\AppData\Local\Programs\Python\Python39\lib\site-packages\botocore\signers.py", line 90, in handler
    return self.sign(operation_name, request)
  File "C:\Users\Katherine\AppData\Local\Programs\Python\Python39\lib\site-packages\botocore\signers.py", line 162, in sign
    auth.add_auth(request)
  File "C:\Users\Katherine\AppData\Local\Programs\Python\Python39\lib\site-packages\botocore\auth.py", line 373, in add_auth
    raise NoCredentialsError()
botocore.exceptions.NoCredentialsError: Unable to locate credentials

似乎我正在尝试下载文件，就好像存储桶是私有的一样，它需要一些配置。但是这个存储桶是公开的，我还没有找到在这种情况下如何访问文件的信息。

Answer 1

如果存储桶及其对象是公开的，您可以只使用对象的公开 URL 来检索所需的对象。公开网址格式如下：

https://.s3-.amazonaws.com/

Answer 2

我猜您还没有设置 aws 凭据 - 秘密和访问密钥。您可以按照以下链接进行操作：

https://boto3.amazonaws.com/v1/documentation/api/latest/guide/credentials.html

如何使用 Python 从公共 AWS S3 存储桶中提取文件

2 个答案: