v0.22 (September 2nd, 2021)

[jdisanti]

This release adds support for three commonly requested features:

• More powerful credential chain
• Support for constructing multiple clients from the same configuration
• Support for Transcribe streaming and S3 Select

In addition, this overhauls client configuration which lead to a number of breaking changes. Detailed changes are inline.

Current Credential Provider Support:

• Environment variables
• Web Identity Token Credentials
• Profile file support (partial)
  • Credentials
    • SSO
    • ECS Credential source
    • IMDS credential source
    • Assume role from source profile
    • Static credentials source profile
    • WebTokenIdentity provider
  • Region
• IMDS
• ECS

Upgrade Guide

If you use <sdk>::Client::from_env

from_env loaded region & credentials from environment variables only. Default sources have been removed from the generated
SDK clients and moved to the aws-config package. Note that the aws-config package default chain adds support for
profile file and web identity token profiles.

1. Add a dependency on aws-config:

   [dependencies]
   aws-config = { git = "https://github.com/awslabs/aws-sdk-rust", tag = "v0.0.17-alpha" }

2. Update your client creation code:

   // `shared_config` can be used to construct multiple different service clients!
   let shared_config = aws_config::load_from_env().await;
   // before: <service>::Client::from_env();
   let client = <service>::Client::new(&shared_config)

If you used <client>::Config::builder()

Config::build() has been modified to not fallback to a default provider. Instead, use aws-config to load and modify
the default chain. Note that when you switch to aws-config, support for profile files and web identity tokens will be added.

1. Add a dependency on aws-config:

   [dependencies]
   aws-config = { git = "https://github.com/awslabs/aws-sdk-rust", tag = "v0.0.17-alpha" }

2. Update your client creation code:

   fn before() {
     let region = aws_types::region::ChainProvider::first_try(<1 provider>).or_default_provider();
     let config = <service>::Config::builder().region(region).build();
     let client = <service>::Client::from_conf(&config);
   }
   
   async fn after() {
     use aws_config::meta::region::RegionProviderChain;
     let region_provider = RegionProviderChain::first_try(<1 provider>).or_default_provider();
     // `shared_config` can be used to construct multiple different service clients!
     let shared_config = aws_config::from_env().region(region_provider).load().await;
     let client = <service>::Client::new(&shared_config)
   }

If you used aws-auth-providers

All credential providers that were in aws-auth-providers have been moved to aws-config. Unless you have a specific use case
for a specific credential provider, you should use the default provider chain:

 let shared_config = aws_config::load_from_env().await;
 let client = <service>::Client::new(&shared_config);

If you maintain your own credential provider

AsyncProvideCredentials has been renamed to ProvideCredentials. The trait has been moved from aws-auth to aws-types.
The original ProvideCredentials trait has been removed. The return type has been changed to by a custom future.

For synchronous use cases:

use aws_types::credentials::{ProvideCredentials, future};

#[derive(Debug)]
struct CustomCreds;
impl ProvideCredentials for CustomCreds {
  fn provide_credentials<'a>(&'a self) -> future::ProvideCredentials<'a>
    where
            Self: 'a,
  {
    // if your credentials are synchronous, use `::ready`
    // if your credentials are loaded asynchronously, use `::new`
    future::ProvideCredentials::ready(todo!()) // your credentials go here
  }
}

For asynchronous use cases:

use aws_types::credentials::{ProvideCredentials, future, Result};

#[derive(Debug)]
struct CustomAsyncCreds;
impl CustomAsyncCreds {
  async fn load_credentials(&self) -> Result {
    Ok(Credentials::from_keys("my creds...", "secret", None))
  }
}

impl ProvideCredentials for CustomCreds {
  fn provide_credentials<'a>(&'a self) -> future::ProvideCredentials<'a>
    where
            Self: 'a,
  {
    future::ProvideCredentials::new(self.load_credentials())
  }
}

Changes

Breaking Changes

• Credential providers from aws-auth-providers have been moved to aws-config (Add Credentials to aws-config #678)

• AsyncProvideCredentials has been renamed to ProvideCredentials. The original non-async provide credentials has been
  removed. See the migration guide above.

• <sevicename>::from_env() has been removed (Minimal Support for Shared Config Loading #675). A drop-in replacement is available:

  1. Add a dependency on aws-config:

     [dependencies]
     aws-config = { git = "https://github.com/awslabs/aws-sdk-rust", tag = "v0.0.17-alpha" }

  2. Update your client creation code:

     let client = <service>>::Client::new(&aws_config::load_from_env().await)

• ProvideRegion has been moved to aws_config::meta::region::ProvideRegion. (Minimal Support for Shared Config Loading #675)

• aws_types::region::ChainProvider has been moved to aws_config::meta::region::RegionProviderChain (Minimal Support for Shared Config Loading #675).

• ProvideRegion is now asynchronous. Code that called provider.region() must be changed to provider.region().await.

• <awsservice>::Config::builder() will not load a default region. To preserve previous behavior:

  1. Add a dependency on aws-config:

     [dependencies]
     aws-config = { git = "https://github.com/awslabs/aws-sdk-rust", tag = "v0.0.17-alpha" }

  2. let shared_config = aws_config::load_from_env().await;
     let config = <service>::config::Builder::from(&shared_config).<other builder modifications>.build();

• Request and Response in smithy_http::operation now use SharedPropertyBag instead of Arc<Mutex<PropertyBag>>. Use the acquire and acquire_mut methods to get a reference to the underlying PropertyBag to access properties. (Add full Event Stream marshalling support and working S3 example #667)

New this week

• 🎉 Add profile file provider for region (Implement the "source" side of profile parsing #594, Create Profile File Provider for Region #682)
• 🎉 Add support for shared configuration between multiple services (Add a minimal implementation of shared config #673)
• 🎉 Add support for Transcribe StartStreamTranscription and S3 SelectObjectContent operations (Add full Event Stream marshalling support and working S3 example #667)
• 🎉 Add support for new MemoryDB service (Update AWS service models #677)
• Improve documentation on collection-aware builders (Improve documentation on collection builders #664)
• Update AWS SDK models (Update AWS service models #677)
• 🐛 Fix sigv4 signing when request ALPN negotiates to HTTP/2. (Fix signing when Hyper ALPN negotiates to h2 #674)
• 🐛 Fix integer size on S3 Size (Customize S3 Size to use correct integer size #679, aws-sdk-rust#209)
• 🐛 Fix JSON parsing issue for modeled empty structs (Fix JSON parsing bug for modeled empty structs #683, aws-sdk-rust#212)
• 🐛 Fix acronym case disagreement between FluentClientGenerator and HttpProtocolGenerator type aliasing (Consolidate fluent client builder implementations #668)

Internal Changes

• Add Event Stream support for restJson1 and restXml (Add incomplete Event Stream support with working Amazon Transcribe example #653, Add full Event Stream marshalling support and working S3 example #667)
• Add NowOrLater future to smithy-async (Add now_or_later future #672)

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This discussion was created from the release v0.22 (September 2nd, 2021).