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Object Storage Service:Determine whether a bucket exists

Last Updated:Nov 01, 2024

A bucket is a container used to store objects in Object Storage Service (OSS). This topic describes how to determine whether a bucket exists.

Usage notes

  • In this topic, the public endpoint of the China (Hangzhou) region is used. If you want to access OSS from other Alibaba Cloud services in the same region as OSS, use an internal endpoint. For more information about OSS regions and endpoints, see Regions, endpoints and open ports.

  • In this topic, access credentials are obtained from environment variables. For more information about how to configure access credentials, see Configure access credentials.

  • In this topic, an OSSClient instance is created by using an OSS endpoint. If you want to create an OSSClient instance by using custom domain names or Security Token Service (STS), see Initialization.

  • To determine whether a bucket exists, you must have the oss:GetBucketAcl permission. For more information, see Attach a custom policy to a RAM user.

Examples

The following code provides an example on how to determine whether a specified bucket exists:

# -*- coding: utf-8 -*-
import oss2
from oss2.credentials import EnvironmentVariableCredentialsProvider
# Obtain access credentials from environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured. 
auth = oss2.ProviderAuthV4(EnvironmentVariableCredentialsProvider())

# Specify the endpoint of the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the endpoint to https://oss-cn-hangzhou.aliyuncs.com. 
endpoint = "https://oss-cn-hangzhou.aliyuncs.com"

# Specify the ID of the region that maps to the endpoint. Example: cn-hangzhou. This parameter is required if you use the signature algorithm V4.
region = "cn-hangzhou"

# Specify the name of your bucket.
bucket = oss2.Bucket(auth, endpoint, "yourBucketName", region=region)

def does_bucket_exist(bucket):
    try:
        bucket.get_bucket_info()
    except oss2.exceptions.NoSuchBucket:
        return False
    except:
        raise
    return True

# Determine whether the specified bucket exists. If the bucket exists, true is returned. Otherwise, false is returned. 
exist = does_bucket_exist(bucket)
if exist:
    print('bucket exist')
else:
    print('bucket not exist')

References

For the complete sample code that is used to determine whether a bucket exists, visit GitHub.