如何轻松确定Boto 3 S3存储桶资源是否存在?

时间:2014-11-11 18:29:17

标签: python amazon-web-services amazon-s3 boto3

例如,我有这段代码:

import boto3

s3 = boto3.resource('s3')

bucket = s3.Bucket('my-bucket-name')

# Does it exist???

6 个答案:

答案 0 :(得分:47)

在撰写本文时,没有高级方法可以快速检查存储桶是否存在并且您可以访问它,但是您可以对HeadBucket操作进行低级调用。这是执行此检查的最便宜的方式:

from botocore.client import ClientError

try:
    s3.meta.client.head_bucket(Bucket=bucket.name)
except ClientError:
    # The bucket does not exist or you have no access.

或者,您也可以反复拨打create_bucket。该操作是幂等的,因此它将创建或仅返回现有存储桶,如果您检查是否存在以了解是否应创建存储桶,这将非常有用:

bucket = s3.create_bucket(Bucket='my-bucket-name')

与往常一样,请务必查看official documentation

注意:在0.0.7版本之前,meta是一个Python字典。

答案 1 :(得分:21)

>>> import boto3
>>> s3 = boto3.resource('s3')
>>> s3.Bucket('Hello') in s3.buckets.all()
False
>>> s3.Bucket('some-docs') in s3.buckets.all()
True
>>> 

答案 2 :(得分:8)

我尝试了Daniel's示例,这真的很有帮助。跟进了boto3文档,这是我的干净测试代码。当存储桶是私有的并且返回'禁止'时,我已经添加了对'403'错误的检查错误。

import boto3, botocore
s3 = boto3.resource('s3')
bucket_name = 'some-private-bucket'
#bucket_name = 'bucket-to-check'

bucket = s3.Bucket(bucket_name)
def check_bucket(bucket):
    try:
        s3.meta.client.head_bucket(Bucket=bucket_name)
        print("Bucket Exists!")
        return True
    except botocore.exceptions.ClientError as e:
        # If a client error is thrown, then check that it was a 404 error.
        # If it was a 404 error, then the bucket does not exist.
        error_code = int(e.response['Error']['Code'])
        if error_code == 403:
            print("Private Bucket. Forbidden Access!")
            return True
        elif error_code == 404:
            print("Bucket Does Not Exist!")
            return False

check_bucket(bucket)

希望这会像我一样帮助一些新人进入boto3。

答案 3 :(得分:4)

我已经成功了:

import boto3

s3 = boto3.resource('s3')
bucket = s3.Bucket('my-bucket-name')

if bucket.creation_date:
   print("The bucket exists")
else:
   print("The bucket does not exist")

答案 4 :(得分:-1)

使用查找功能 - >如果存在桶存在

,则返回None
if s3.lookup(bucketName) is None:
    bucket=s3.create_bucket(bucketName) # Bucket Don't Exist
else:
    bucket = s3.get_bucket(bucketName) #Bucket Exist

答案 5 :(得分:-2)

你可以使用conn.get_bucket

from boto.s3.connection import S3Connection
from boto.exception import S3ResponseError    

conn = S3Connection(aws_access_key, aws_secret_key)

try:
    bucket = conn.get_bucket(unique_bucket_name, validate=True)
except S3ResponseError:
    bucket = conn.create_bucket(unique_bucket_name)

引用http://boto.readthedocs.org/en/latest/s3_tut.html

上的文档
  

从Boto v2.25.0开始,现在执行HEAD请求(更便宜但更糟糕的错误消息)。