如何从 boto3 的配置文件中检索 mfa_serial？

Question

In my ~/.aws/config file I have:

[dev]
region = us-east-1
output = json
mfa_serial = arn:aws:iam::1111:mfa/user

How do I retrieve that mfa_serial from the config in boto3 so I don't have to specify the arn in the py script?

sts = session.client('sts')
mfa_code = input("Enter the MFA code: ")
mfa_session = sts.get_session_token(
    DurationSeconds=3600,
    SerialNumber=mfa_serial,
    TokenCode=mfa_code
)

Answer 1

You can get the mfa_serial defined in the current config file using botocore.session.get_scoped_config

from botocore.session import Session
Session().get_scoped_config().get('mfa_serial')

Answer 2

If you're okay getting username input you can get the MFA arn programmatically using list_mfa_devices .

This snippet requests the User's IAM name and then retrieves the MFA information.

import boto3

iam = session.client('iam')
user = input("Username: ")
response = iam.list_mfa_devices(UserName=user)['MFADevices']
mfa = next(iter(response))['SerialNumber']
print(mfa)

The output will be this format:

arn:aws:iam::123456789123:mfa/amandahugginkiss

References

https://boto3.amazonaws.com/v1/documentation/api/latest/reference/services/iam.html#IAM.Client.list_mfa_devices