FIX: extract reason from error in AWSSdk2Transport

[chenqi0805]

Description

This is for resolving missing cause message when there is no proper permission to access Fine grained Access Control Amazon Opensearch domain.

Exception in thread "main" org.opensearch.client.opensearch._types.OpenSearchException: Request failed: [security_exception] authentication/authorization failure
	at org.opensearch.client.transport.aws.AwsSdk2Transport.parseResponse(AwsSdk2Transport.java:517)
	at org.opensearch.client.transport.aws.AwsSdk2Transport.executeSync(AwsSdk2Transport.java:438)
	at org.opensearch.client.transport.aws.AwsSdk2Transport.performRequest(AwsSdk2Transport.java:241)
	at org.opensearch.client.opensearch.OpenSearchClient.bulk(OpenSearchClient.java:211)
	at org.opensearch.dataprepper.plugins.sink.opensearch.index.TestClient.testBulk(TestClient.java:215)
	at org.opensearch.dataprepper.plugins.sink.opensearch.index.TestClient.main(TestClient.java:80)

Issues Resolved

Closes #473

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.
For more information on following Developer Certificate of Origin and signing off your commits, please check here.

[wbeckler]

Thank you for submitting this! Can you think of a scenario in which an application might be relying on the previous behavior? As in, could this possibly be a breaking change?

[chenqi0805]

@wbeckler The only scenario I can think of is when both reason and message is present but so far it is hypothetical as I have not found such case. Do you have other scenario in your head?

[wbeckler]

@wbeckler The only scenario I can think of is when both reason and message is present but so far it is hypothetical as I have not found such case. Do you have other scenario in your head?

Not really. What you're saying makes sense, but I ask the question in case there's something I'm not thinking of.

[VachaShah]

LGTM! Just a minor comment.

[VachaShah]

Nit: Remove this line.

[dblock]

Looks good, but needs tests please.

[chenqi0805]

@dblock Thanks for the suggestion. I do not find a good strategy to unit test so I put a AwsSdk2SecurityIT that needs to be run against a FGAC without proper permission.

[dblock]

Without looking at the code, do we not have a way to mock a response? If it's really hard, care to open an issue to add tests that exercise all these paths and we'll merge as is? Also @reta wdyt?

[chenqi0805]

@dblock I agree we should open issue to use unit test to cover paths in Awssdk2Transport. ref: #503

[reta]

Without looking at the code, do we not have a way to mock a response? If it's really hard, care to open an issue to add tests that exercise all these paths and we'll merge as is? Also @reta wdyt?

Sounds reasonable @dblock , we may need to come up with some mocks (like test fixtures we do in core) but it may take some efforts.

[reta]

LGMT! @chenqi0805 there are conflicts, could you please resolve them? thank you

[chenqi0805]

@reta resolved conflict

[reta]

@dblock LGTY? thanks!

[chenqi0805]

@dblock Need your approval for unblocking merge