NoCredentialProviders/UnknownOperationException when using --region

[cjbradfield]

In some (all?) regions, if you use the --region flag, kiam-server will fail to get credentials from the EC2 Metadata server to make the STS call.

You'll see errors like the following:

{"generation.metadata":0,"level":"error","msg":"error warming credentials: NoCredentialProviders: no valid providers in chain\ncaused by: EnvAccessKeyNotFound: failed to find credentials in the environment.\nSharedCredsLoad: failed to load profile, .\nEC2RoleRequestError: no EC2 instance role found\ncaused by
: EC2MetadataError: failed to make EC2Metadata request\ncaused by: \u003cUnknownOperationException/\u003e\n...

The reason is the --region flag defines an endpoint resolver, but doesn't constrain the resolver to the sts service. Fix is incoming.

[cjbradfield]

#344 is possibly related