access IBM COS with aws-rust-sdk

from_env.rs

use aws_sdk_s3::Client;

// sample bucket name of an existing bucket
const BUCKET_NAME: &str = "sweap-ui-test-dev";

/// create a service-key with HMAC enabled,
/// get the content like this: `ibmcloud resource service-key my-key`
///
/// set the environment-variables:
/// AWS_ACCESS_KEY_ID= the cos_hmac_keys.access_key_id
/// AWS_SECRET_ACCESS_KEY = the cos_hmac_keys.secret_access_key
/// AWS_REGION = "dummy"
#[tokio::main]
async fn main() -> anyhow::Result<()> {
    let config = aws_config::from_env()
        // get this from the endpoints section of the Cloud Object Storage resource
        .endpoint_url("https://s3.eu-de.cloud-object-storage.appdomain.cloud")
        // .region("dummy")
        .load()
        .await;

    let client = Client::new(&config);

    let response = client.list_objects_v2().bucket(BUCKET_NAME).send().await?;

    for object in response.contents() {
        println!("{}", object.key().unwrap_or_default());
    }

    Ok(())
}

hardcoded.rs

use aws_config::Region;
use aws_credential_types::provider::SharedCredentialsProvider;
use aws_credential_types::Credentials;
use aws_sdk_s3::Client;

/// create a service-key with HMAC enabled,
/// get the content like this: `ibmcloud resource service-key my-key`

const AWS_ACCESS_KEY_ID: &str = "this is cos_hmac_keys.access_key_id";
const AWS_SECRET_ACCESS_KEY: &str = "this is cos_hmac_keys.secret_access_key";
// get this from the endpoints section of the Cloud Object Storage resource
const ENDPOINT_URL: &str = "https://s3.eu-de.cloud-object-storage.appdomain.cloud";
const BUCKET_NAME: &str = "sample bucket name to list";

#[tokio::main]
async fn main() -> anyhow::Result<()> {
    let c = Credentials::new(
        AWS_ACCESS_KEY_ID,
        AWS_SECRET_ACCESS_KEY,
        None,
        None,
        "hardcoded-credentials",
    );
    let c = SharedCredentialsProvider::new(c);
    let config = aws_config::SdkConfig::builder()
        .credentials_provider(c)
        .endpoint_url(ENDPOINT_URL)
        // if not set, will error with "A region must be set when sending requests to S3."
        .region(Some(Region::new("dummy")))
        .build();

    let client = Client::new(&config);

    let response = client.list_objects_v2().bucket(BUCKET_NAME).send().await?;

    for object in response.contents() {
        println!("{}", object.key().unwrap_or_default());
    }

    Ok(())
}