Specifying your credentials and default region - AWS SDK for Rust
Specifying a region

This is documentation for the developer preview release of the AWS SDK for Rust. Do not use it in production as it is subject to breaking changes.

Specifying your credentials and default region

To make an API call using the AWS SDK for Rust (the SDK), you must supply credentials. Two values comprise credentials: an Access Key ID and a Secret Access Key. If you haven't created these two values, see the Getting started with the AWS SDK for Rust topic for information on retrieving your credentials.

Once you have your credentials, the SDK can access them from any of the following locations (when it finds credentials, the SDK quits looking further):

  • In the environment variables AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY.

  • In Web Identity Token credentials from the environment or container (including EKS)

  • ECS credentials (IAM roles for tasks)

  • As entries in the credentials file in the .aws directory in your home directory (~/.aws/credentials on Linux, OS X, and Unix; %userprofile%\.aws\credentials on Microsoft Windows):

    [default]
aws_access_key_id=YOUR-ACCESS-KEY
aws_secret_access_key=YOUR-SECRET-KEY

  • Using a named profile specified in the credentials file via the AWS_PROFILE environment variable.

  • From the EC2 Instance Metadata Service (IAM Roles attached to an instance)

Specifying a region

Since most resources live in a specific AWS Region, it's imperative that you supply the correct region for the resource when using the SDK. Much as the SDK searches for credentials in a specific order, so does it search for a region. The SDK looks in the following order for a default region:

  • In the environment variable AWS_REGION.

  • As an entry in the credentials file in the .aws directory in your home directory (~/.aws/credentials on Linux, OS X, and Unix; %userprofile%\.aws\credentials on Microsoft Windows):

    [default]
region=YOUR-DEFAULT-REGION

  • As an entry in the config file in the .aws directory in your home directory (~/.aws/config on Linux, OS X, and Unix; %userprofile%\.aws\config on Microsoft Windows):

    [default]
region=YOUR-DEFAULT-REGION