如何使用Boto3（Python）列出可用区域

Question

As AWS expands and adds new regions, I'd like to have my code automatically detect that. Currently, the "Select your region" is hard coded but I would like to parse the following for just the RegionName .

import boto3

ec2 = boto3.client('ec2')
regions = ec2.describe_regions()
print(regions)

My output is JSON like so:

{'Regions': [{'Endpoint': 'ec2.ap-south-1.amazonaws.com', 'RegionName': 'ap-south-1'}, {'Endpoint': 'ec2.eu-west-1.amazonaws.com', 'RegionName': 'eu-west-1'}, {'Endpoint': 'ec2.ap-southeast-1.amazonaws.com', 'RegionName': 'ap-southeast-1'}]}

I've trimmed off the repeating data and the ResponseMetadata for the sake of space.

How can I parse the RegionName into a list?

Answer 1

In addition to Frédéric's answer, you can also get known regions for each service without making any service calls. I will caution you, however, that since this is pulling from botocore's local models rather than hitting an endpoint, it will not always be exhaustive since you need to update botocore to update the list.

from boto3.session import Session

s = Session()
dynamodb_regions = s.get_available_regions('dynamodb')

Additionally, you are not restricted to the regions in this list. If you are using an older version of botocore you can still use new regions by specifying them. They just won't appear in this list.

Answer 2

The following will return you the RegionName and Endpoint for each region.

# List all regions
client = boto3.client('ec2')
regions = [region['RegionName'] for region in client.describe_regions()['Regions']]