Serveral implemented services seems to return errors in a format that AWS Java SDK 2 can't handle

[Code and such]

TLDR/Summary

It seems like a number of the implemented services return responses with errors that the AWS Java SDK v2 clients can't/won't parse.

Moto places many errors in ErrorResponse.Errors[].Error and the SDK expects one error, at ErrorResponse.Error

The reason I say "a number of services" is that I've reported an error like this for SES, and now encountered exactly the same thing in IAM.

Comparing a moto response and an AWS response:

Moto:

<?xml version="1.0" encoding="UTF-8"?>
  <ErrorResponse>
    <Errors>
      <Error>
        <Code>InvalidParameterValue</Code>
        <Message><![CDATA[Value ({"Version": "2012-10-17","Statement": [{"Effect": "Allow","Action": ["ses:SendRawEmail","ses:SendEmail"],"Resource": "*"}]}) for parameter PermissionsBoundary is invalid.]]></Message> 
      </Error>
    </Errors>
  <RequestId>uVSbWjsjxHXHgOz6bM0K4QqKE3vMn6D5U0KWe2nG0z9pbfJn32Q8</RequestId>
</ErrorResponse>

AWS:

<ErrorResponse xmlns="https://sts.amazonaws.com/doc/2011-06-15/">
  <Error>
    <Type>Sender</Type>
    <Code>ValidationError</Code>
    <Message>1 validation error detected: Value 'non-existing' at 'roleArn' failed to satisfy constraint: Member must have length greater than or equal to 20</Message>
  </Error>
  <RequestId>a77221e6-f9fa-41a5-9b84-ccdeb7c2b0da</RequestId>
</ErrorResponse>

Versions:

Moto image version motoserver/moto:5.0.6
Java SDK version: 2.25.40

Notes

It's worth pointing out that all AWS v2 clients I've seen so far use a common library to parse errors (and a bunch more). It's thus likely that most (all?) services will return errors in this format.

Like mentioned I use the AWS v2 clients. That is information is sent in the user agent header and it is possible that the server acts on that, and use a different response format. But I haven't confirmed this. Just a thought.

Refs:

The issue I reported on SES:
#7339

[Bert Blommers]

Hi @code-and-such, can you share an example call that fails for you? I've just tested it out with the get_role-method, and the exception that we throw there is handled just fine by the Java SDK:

GetRoleRequest getRequest = GetRoleRequest.builder().roleName("unknown").build();

try {
    iam.getRole(getRequest);
    assertTrue("This should fail, as the rolename is invalid", false);
} catch (NoSuchEntityException e) {
    assertTrue(e.getMessage().contains("Role unknown not found"));
}