Boto3 get only S3 buckets of specific region

Question

The following code sadly lists all buckets of all regions and not only from "eu-west-1" as specified. How can I change that?

import boto3

s3 = boto3.client("s3", region_name="eu-west-1")

for bucket in s3.list_buckets()["Buckets"]:

    bucket_name = bucket["Name"]
    print(bucket["Name"])

Answer 1

s3 = boto3.client("s3", region_name="eu-west-1")

connects to S3 API endpoint in eu-west-1. It doesn't limit the listing to eu-west-1 buckets. One solution is to query the bucket location and filter.

s3 = boto3.client("s3")

for bucket in s3.list_buckets()["Buckets"]:
    if s3.get_bucket_location(Bucket=bucket['Name'])['LocationConstraint'] == 'eu-west-1':
        print(bucket["Name"])

If you need a one liner using Python's list comprehension:

region_buckets = [bucket["Name"] for bucket in s3.list_buckets()["Buckets"] if s3.get_bucket_location(Bucket=bucket['Name'])['LocationConstraint'] == 'eu-west-1']
print(region_buckets)

Answer 2

The solution above does not always work for buckets in some US regions because the 'LocationConstraint' can be null. Here is another solution:

s3 = boto3.client("s3")

for bucket in s3.list_buckets()["Buckets"]:
    if s3.head_bucket(Bucket=bucket['Name'])['ResponseMetadata']['HTTPHeaders']['x-amz-bucket-region'] == 'us-east-1':
        print(bucket["Name"])

The SDK method:

s3.head_bucket(Bucket=[INSERT_BUCKET_NAME_HERE])['ResponseMetadata']['HTTPHeaders']['x-amz-bucket-region']

... should always give you the bucket region. Thanks to sd65 for the tip: https://github.com/boto/boto3/issues/292