Generate the AWS HTTP signature from boto3

Question

I am working with the AWS Transcribe streaming service that boto3 does not support yet, so to make HTTP/2 requests, I need to manually setup the authorization header with the "AWS Signature Version 4"

I've found some example implementation, but I was hoping to just call whatever function boto3/botocore have implemented using the same configuration object.

Something like

    session = boto3.Session(...)
    auth = session.generate_signature('POST', '/stream-transcription', ...)

Any pointers in that direction?

user_4779904 · Answer

Contrary to the AWS SDKs for most other programming languages, boto3/botocore don't offer the functionality to sign arbitrary requests using "AWS Signature Version 4" yet. However there is at least already an open feature request for that: https://github.com/boto/botocore/issues/1784

In this feature request, existing alternatives are discussed as well. One is the third-party Python library aws-requests-auth, which provides a thin wrapper around botocore and requests to sign HTTP-requests. That looks like the following:

import requests
from aws_requests_auth.boto_utils import BotoAWSRequestsAuth

auth = BotoAWSRequestsAuth(aws_host="your-service.domain.tld",
                           aws_region="us-east-1",
                           aws_service="execute-api")
response = requests.get("https://your-service.domain.tld",
                        auth=auth)

Another alternative presented in the feature request is to implement the necessary glue-code on your own, as shown in the following gist: https://gist.github.com/rhboyd/1e01190a6b27ca4ba817bf272d5a5f9a.

user_3335508 · Answer

Did you check this SDK? Seems very recent but might do what you need.

https://github.com/awslabs/amazon-transcribe-streaming-sdk/tree/master

It looks like it handles the signing: https://github.com/awslabs/amazon-transcribe-streaming-sdk/blob/master/amazon_transcribe/signer.py

user_87858 · Answer

I have not tested this, but you can likely accomplish this by following along with with this SigV4 unit test:

https://github.com/boto/botocore/blob/master/tests/unit/test_auth_sigv4.py

Note, this constructs a request using the botocore.awsrequest.AWSRequest helper. You'll likely need to dig around to figure out how to send the actual HTTP request (perhaps with httpsession.py)

Generate the AWS HTTP signature from boto3

3 Answers