Can't even get the most basic default credentials to work in Rust

[trevorstr]

I have an access key and secret key, with appropriate permissions. I can use the AWS CLI tool to call APIs that I have policy permissions to (Rekognition).

In the Rust SDK, I can't even get the most basic example, using the default credentials profile, to work.

let region = RegionProviderChain::default_provider().or_else("us-west-2");
let creds = DefaultCredentialsChain::builder().build().await;
let cfg = aws_config::from_env().region(region).credentials_provider(creds).load().await;

This yields:

DispatchFailure(DispatchFailure { source: ConnectorError { kind: Other(None), source: CredentialsNotLoaded(CredentialsNotLoaded { source: "no providers in chain provided credentials" }), connection: Unknown } })

How are you supposed to use the default profile in ~/.aws/credentials?

[trevorstr]

I would expect this to work as well, even more simply.

let cfg = aws_config::load_from_env().await;
let rek_client = rek::client::Client::new(&cfg);

However, this tells me that the Region is missing, even though I specified REGION in my ~/.aws/credentials file, under the [default] profile, just like every other SDK uses.

DispatchFailure(DispatchFailure { source: ConnectorError { kind: Other(None), source: ResolveEndpointError { message: "Invalid Configuration: Missing Region", source: None }, connection: Unknown } })

In fact, when I run aws configure list, I can see the correct credentials and region being used, from the credentials file. Only the Rust SDK exhibits this problem.

[trevorstr]

I figured out the problem. It's another inconsistency in AWS, related to case insensitivity. #1020