Compatibility with AWS SDK JS v3 KMS client and X-Ray SDK captureAWSv3Client

[aripalo]

Problem:

Apparently this library should support SDK JS v3 KMS client (see #916), but it seems that constructing one's own client provider with v3 KMS client (that is captured with X-Ray) is not possible? Or what am I missing?

This relates to issue #191 which suggest capturing v2 client like so:

const AWSXRay = require('aws-xray-sdk')
const { getKmsClient, cacheClients } = require('@aws-crypto/client-node')
const clientProvider = cacheClients(region => AWSXRay.captureAWSClient(getKmsClient(region)))

… but one can't utilize captureAWSv3Client as it seems that getKmsClient is only returning v2 SDK (API compatible) client (and v2 has been deprecated):

import { captureAWSv3Client } from "aws-xray-sdk-core";

const clientProvider = cacheClients((region) => captureAWSv3Client(getKmsClient(region)));

Solution:

Unfortunately I don't yet understand the inner architecture of the Encryption SDK, but on a high-level, it should be possible to just use SDK v3 modules (with X-Ray capture/tracing) as v2 has been deprecated.

If this is already supported, it should be somehow covered by the docs or at least by the examples.

[clementallen]

@aripalo I was able to add X-Ray tracing for a Lambda use case without issues:

const clientProvider = cacheClients((region) => tracer.captureAWSv3Client(getKmsClient(region)));

This was using the Lambda Powertools library, docs here: https://docs.powertools.aws.dev/lambda/typescript/latest/core/tracer/#patching-aws-sdk-clients

I can't imagine the implementation under the hood of Powertools is much different to aws-xray-sdk-core.