Add SharedAsyncSleep wrapping Arc<dyn AsyncSleep> (#2742)

## Motivation and Context
Add `SharedAsyncSleep` wrapping `Arc<dyn AsyncSleep>` and update call
sites of `Arc<dyn AsyncSleep>` to use `SharedAsyncSleep`

## Description
Public APIs that take/return a trait object for `AsyncSleep` have been
using `Arc<dyn AsyncSleep>` in the codebase. This has a downside of
exposing a bare `Arc`, making it difficult to change the APIs in the
future without breaking backwards compatibility. This PR adds a newtype
wrapper `SharedAsyncSleep` that hides `Arc<dyn AsyncSleep>` to alleviate
the said issue (the idiom of having `SharedXXX` has been seen in the
codebase, e.g. `SharedTimeSource`, `SharedCredentialsProvider`, and so
on).

## Testing
- [x] Passed tests in CI

## Checklist
<!--- If a checkbox below is not applicable, then please DELETE it
rather than leaving it unchecked -->
- [x] I have updated `CHANGELOG.next.toml` if I made changes to the
smithy-rs codegen or runtime crates
- [x] I have updated `CHANGELOG.next.toml` if I made changes to the AWS
SDK, generated SDK code, or SDK runtime crates

----

_By submitting this pull request, I confirm that you can use, modify,
copy, and redistribute this contribution, under the terms of your
choice._

---------

Co-authored-by: Yuki Saito <awsaito@amazon.com>
Co-authored-by: John DiSanti <jdisanti@amazon.com>

Author: ysaito1001

CHANGELOG.next.toml

@@ -121,3 +121,15 @@ message = "The SDK has added support for timestreamwrite and timestreamquery. Su
 meta = { "breaking" = false, "tada" = true, "bug" = false }
 references = ["smithy-rs#2707", "aws-sdk-rust#114"]
 author = "rcoh"
+
+[[smithy-rs]]
+message = "A newtype wrapper `SharedAsyncSleep` has been introduced and occurrences of `Arc<dyn AsyncSleep>` that appear in public APIs have been replaced with it."
+references = ["smithy-rs#2742"]
+meta = { "breaking" = true, "tada" = false, "bug" = false, "target" = "client" }
+author = "ysaito1001"
+
+[[aws-sdk-rust]]
+message = "A newtype wrapper `SharedAsyncSleep` has been introduced and occurrences of `Arc<dyn AsyncSleep>` that appear in public APIs have been replaced with it."
+references = ["smithy-rs#2742"]
+meta = { "breaking" = true, "tada" = false, "bug" = false }
+author = "ysaito1001"

aws/rust-runtime/aws-config/src/connector.rs

@@ -19,11 +19,11 @@ pub use aws_smithy_client::conns::default_connector;
 #[cfg(all(feature = "native-tls", not(feature = "allow-compilation")))]
 compile_error!("Feature native-tls has been removed. For upgrade instructions, see: https://awslabs.github.io/smithy-rs/design/transport/connector.html");
 
-/// Given `ConnectorSettings` and an `AsyncSleep`, create a `DynConnector` from defaults depending on what cargo features are activated.
+/// Given `ConnectorSettings` and a [`SharedAsyncSleep`](aws_smithy_async::rt::sleep::SharedAsyncSleep), create a `DynConnector` from defaults depending on what cargo features are activated.
 #[cfg(not(feature = "client-hyper"))]
 pub fn default_connector(
     _settings: &aws_smithy_client::http_connector::ConnectorSettings,
-    _sleep: Option<std::sync::Arc<dyn aws_smithy_async::rt::sleep::AsyncSleep>>,
+    _sleep: Option<aws_smithy_async::rt::sleep::SharedAsyncSleep>,
 ) -> Option<DynConnector> {
     None
 }

aws/rust-runtime/aws-config/src/imds/client/token.rs

@@ -18,7 +18,7 @@ use crate::imds::client::error::{ImdsError, TokenError, TokenErrorKind};
 use crate::imds::client::ImdsResponseRetryClassifier;
 use aws_credential_types::cache::ExpiringCache;
 use aws_http::user_agent::UserAgentStage;
-use aws_smithy_async::rt::sleep::AsyncSleep;
+use aws_smithy_async::rt::sleep::SharedAsyncSleep;
 use aws_smithy_async::time::SharedTimeSource;
 use aws_smithy_client::erase::DynConnector;
 use aws_smithy_client::retry;
@@ -84,7 +84,7 @@ impl TokenMiddleware {
         token_ttl: Duration,
         retry_config: retry::Config,
         timeout_config: TimeoutConfig,
-        sleep_impl: Option<Arc<dyn AsyncSleep>>,
+        sleep_impl: Option<SharedAsyncSleep>,
     ) -> Self {
         let mut inner_builder = aws_smithy_client::Client::builder()
             .connector(connector)

aws/rust-runtime/aws-config/src/lib.rs

@@ -154,7 +154,7 @@ mod loader {
 
     use aws_credential_types::cache::CredentialsCache;
     use aws_credential_types::provider::{ProvideCredentials, SharedCredentialsProvider};
-    use aws_smithy_async::rt::sleep::{default_async_sleep, AsyncSleep};
+    use aws_smithy_async::rt::sleep::{default_async_sleep, AsyncSleep, SharedAsyncSleep};
     use aws_smithy_async::time::{SharedTimeSource, TimeSource};
     use aws_smithy_client::http_connector::HttpConnector;
     use aws_smithy_types::retry::RetryConfig;
@@ -185,7 +185,7 @@ mod loader {
         endpoint_url: Option<String>,
         region: Option<Box<dyn ProvideRegion>>,
         retry_config: Option<RetryConfig>,
-        sleep: Option<Arc<dyn AsyncSleep>>,
+        sleep: Option<SharedAsyncSleep>,
         timeout_config: Option<TimeoutConfig>,
         provider_config: Option<ProviderConfig>,
         http_connector: Option<HttpConnector>,
@@ -260,7 +260,7 @@ mod loader {
         /// is used to create timeout futures.
         pub fn sleep_impl(mut self, sleep: impl AsyncSleep + 'static) -> Self {
             // it's possible that we could wrapping an `Arc in an `Arc` and that's OK
-            self.sleep = Some(Arc::new(sleep));
+            self.sleep = Some(SharedAsyncSleep::new(sleep));
             self
         }
 

aws/rust-runtime/aws-config/src/provider_config.rs

@@ -6,7 +6,7 @@
 //! Configuration Options for Credential Providers
 
 use aws_credential_types::time_source::TimeSource;
-use aws_smithy_async::rt::sleep::{default_async_sleep, AsyncSleep};
+use aws_smithy_async::rt::sleep::{default_async_sleep, AsyncSleep, SharedAsyncSleep};
 use aws_smithy_async::time::SharedTimeSource;
 use aws_smithy_client::erase::DynConnector;
 use aws_smithy_types::error::display::DisplayErrorContext;
@@ -41,7 +41,7 @@ pub struct ProviderConfig {
     fs: Fs,
     time_source: SharedTimeSource,
     connector: HttpConnector,
-    sleep: Option<Arc<dyn AsyncSleep>>,
+    sleep: Option<SharedAsyncSleep>,
     region: Option<Region>,
     /// An AWS profile created from `ProfileFiles` and a `profile_name`
     parsed_profile: Arc<OnceCell<Result<ProfileSet, ProfileFileLoadError>>>,
@@ -65,7 +65,7 @@ impl Debug for ProviderConfig {
 impl Default for ProviderConfig {
     fn default() -> Self {
         let connector = HttpConnector::ConnectorFn(Arc::new(
-            |settings: &ConnectorSettings, sleep: Option<Arc<dyn AsyncSleep>>| {
+            |settings: &ConnectorSettings, sleep: Option<SharedAsyncSleep>| {
                 default_connector(settings, sleep)
             },
         ));
@@ -195,7 +195,7 @@ impl ProviderConfig {
     }
 
     #[allow(dead_code)]
-    pub(crate) fn sleep(&self) -> Option<Arc<dyn AsyncSleep>> {
+    pub(crate) fn sleep(&self) -> Option<SharedAsyncSleep> {
         self.sleep.clone()
     }
 
@@ -332,8 +332,7 @@ impl ProviderConfig {
         C::Future: Unpin + Send + 'static,
         C::Error: Into<Box<dyn std::error::Error + Send + Sync + 'static>>,
     {
-        let connector_fn = move |settings: &ConnectorSettings,
-                                 sleep: Option<Arc<dyn AsyncSleep>>| {
+        let connector_fn = move |settings: &ConnectorSettings, sleep: Option<SharedAsyncSleep>| {
             let mut builder = aws_smithy_client::hyper_ext::Adapter::builder()
                 .connector_settings(settings.clone());
             if let Some(sleep) = sleep {
@@ -350,7 +349,7 @@ impl ProviderConfig {
     /// Override the sleep implementation for this configuration
     pub fn with_sleep(self, sleep: impl AsyncSleep + 'static) -> Self {
         ProviderConfig {
-            sleep: Some(Arc::new(sleep)),
+            sleep: Some(SharedAsyncSleep::new(sleep)),
             ..self
         }
     }

aws/rust-runtime/aws-credential-types/external-types.toml

@@ -1,3 +1,3 @@
 allowed_external_types = [
-    "aws_smithy_async::rt::sleep::AsyncSleep",
+    "aws_smithy_async::rt::sleep::SharedAsyncSleep",
 ]

aws/rust-runtime/aws-credential-types/src/cache/lazy_caching.rs

@@ -5,11 +5,10 @@
 
 //! Lazy, credentials cache implementation
 
-use std::sync::Arc;
 use std::time::{Duration, Instant};
 
 use aws_smithy_async::future::timeout::Timeout;
-use aws_smithy_async::rt::sleep::AsyncSleep;
+use aws_smithy_async::rt::sleep::{AsyncSleep, SharedAsyncSleep};
 use tracing::{debug, info, info_span, Instrument};
 
 use crate::cache::{ExpiringCache, ProvideCachedCredentials};
@@ -25,7 +24,7 @@ const DEFAULT_BUFFER_TIME_JITTER_FRACTION: fn() -> f64 = fastrand::f64;
 #[derive(Debug)]
 pub(crate) struct LazyCredentialsCache {
     time: TimeSource,
-    sleeper: Arc<dyn AsyncSleep>,
+    sleeper: SharedAsyncSleep,
     cache: ExpiringCache<Credentials, CredentialsError>,
     provider: SharedCredentialsProvider,
     load_timeout: Duration,
@@ -37,7 +36,7 @@ pub(crate) struct LazyCredentialsCache {
 impl LazyCredentialsCache {
     fn new(
         time: TimeSource,
-        sleeper: Arc<dyn AsyncSleep>,
+        sleeper: SharedAsyncSleep,
         provider: SharedCredentialsProvider,
         load_timeout: Duration,
         buffer_time: Duration,
@@ -133,12 +132,11 @@ use crate::Credentials;
 pub use builder::Builder;
 
 mod builder {
-    use std::sync::Arc;
     use std::time::Duration;
 
     use crate::cache::{CredentialsCache, Inner};
     use crate::provider::SharedCredentialsProvider;
-    use aws_smithy_async::rt::sleep::{default_async_sleep, AsyncSleep};
+    use aws_smithy_async::rt::sleep::{default_async_sleep, SharedAsyncSleep};
 
     use super::TimeSource;
     use super::{
@@ -160,7 +158,7 @@ mod builder {
     /// `build` to create a `LazyCredentialsCache`.
     #[derive(Clone, Debug, Default)]
     pub struct Builder {
-        sleep: Option<Arc<dyn AsyncSleep>>,
+        sleep: Option<SharedAsyncSleep>,
         time_source: Option<TimeSource>,
         load_timeout: Option<Duration>,
         buffer_time: Option<Duration>,
@@ -174,22 +172,22 @@ mod builder {
             Default::default()
         }
 
-        /// Implementation of [`AsyncSleep`] to use for timeouts.
+        /// Implementation of [`AsyncSleep`](aws_smithy_async::rt::sleep::AsyncSleep) to use for timeouts.
         ///
         /// This enables use of the `LazyCredentialsCache` with other async runtimes.
         /// If using Tokio as the async runtime, this should be set to an instance of
         /// [`TokioSleep`](aws_smithy_async::rt::sleep::TokioSleep).
-        pub fn sleep(mut self, sleep: Arc<dyn AsyncSleep>) -> Self {
+        pub fn sleep(mut self, sleep: SharedAsyncSleep) -> Self {
             self.set_sleep(Some(sleep));
             self
         }
 
-        /// Implementation of [`AsyncSleep`] to use for timeouts.
+        /// Implementation of [`AsyncSleep`](aws_smithy_async::rt::sleep::AsyncSleep) to use for timeouts.
         ///
         /// This enables use of the `LazyCredentialsCache` with other async runtimes.
         /// If using Tokio as the async runtime, this should be set to an instance of
         /// [`TokioSleep`](aws_smithy_async::rt::sleep::TokioSleep).
-        pub fn set_sleep(&mut self, sleep: Option<Arc<dyn AsyncSleep>>) -> &mut Self {
+        pub fn set_sleep(&mut self, sleep: Option<SharedAsyncSleep>) -> &mut Self {
             self.sleep = sleep;
             self
         }
@@ -347,7 +345,7 @@ mod tests {
     use std::sync::{Arc, Mutex};
     use std::time::{Duration, SystemTime, UNIX_EPOCH};
 
-    use aws_smithy_async::rt::sleep::TokioSleep;
+    use aws_smithy_async::rt::sleep::{SharedAsyncSleep, TokioSleep};
     use tracing::info;
     use tracing_test::traced_test;
 
@@ -372,7 +370,7 @@ mod tests {
         let load_list = Arc::new(Mutex::new(load_list));
         LazyCredentialsCache::new(
             time,
-            Arc::new(TokioSleep::new()),
+            SharedAsyncSleep::new(TokioSleep::new()),
             SharedCredentialsProvider::new(provide_credentials_fn(move || {
                 let list = load_list.clone();
                 async move {
@@ -414,7 +412,7 @@ mod tests {
         }));
         let credentials_cache = LazyCredentialsCache::new(
             TimeSource::testing(&time),
-            Arc::new(TokioSleep::new()),
+            SharedAsyncSleep::new(TokioSleep::new()),
             provider,
             DEFAULT_LOAD_TIMEOUT,
             DEFAULT_BUFFER_TIME,
@@ -534,7 +532,7 @@ mod tests {
         let time = TestingTimeSource::new(epoch_secs(100));
         let credentials_cache = LazyCredentialsCache::new(
             TimeSource::testing(&time),
-            Arc::new(TokioSleep::new()),
+            SharedAsyncSleep::new(TokioSleep::new()),
             SharedCredentialsProvider::new(provide_credentials_fn(|| async {
                 aws_smithy_async::future::never::Never::new().await;
                 Ok(credentials(1000))

aws/rust-runtime/aws-inlineable/src/endpoint_discovery.rs

@@ -5,8 +5,8 @@
 
 //! Maintain a cache of discovered endpoints
 
-use aws_smithy_async::rt::sleep::AsyncSleep;
-use aws_smithy_async::time::TimeSource;
+use aws_smithy_async::rt::sleep::{AsyncSleep, SharedAsyncSleep};
+use aws_smithy_async::time::SharedTimeSource;
 use aws_smithy_client::erase::boxclone::BoxFuture;
 use aws_smithy_http::endpoint::{ResolveEndpoint, ResolveEndpointError};
 use aws_smithy_types::endpoint::Endpoint;
@@ -24,8 +24,8 @@ pub struct ReloadEndpoint {
     endpoint: Arc<Mutex<Option<ExpiringEndpoint>>>,
     error: Arc<Mutex<Option<ResolveEndpointError>>>,
     rx: Receiver<()>,
-    sleep: Arc<dyn AsyncSleep>,
-    time: Arc<dyn TimeSource>,
+    sleep: SharedAsyncSleep,
+    time: SharedTimeSource,
 }
 
 impl Debug for ReloadEndpoint {
@@ -106,8 +106,8 @@ impl ExpiringEndpoint {
 
 pub(crate) async fn create_cache<F>(
     loader_fn: impl Fn() -> F + Send + Sync + 'static,
-    sleep: Arc<dyn AsyncSleep>,
-    time: Arc<dyn TimeSource>,
+    sleep: SharedAsyncSleep,
+    time: SharedTimeSource,
 ) -> Result<(EndpointCache, ReloadEndpoint), ResolveEndpointError>
 where
     F: Future<Output = Result<(Endpoint, SystemTime), ResolveEndpointError>> + Send + 'static,
@@ -155,9 +155,9 @@ impl EndpointCache {
 #[cfg(test)]
 mod test {
     use crate::endpoint_discovery::create_cache;
-    use aws_smithy_async::rt::sleep::TokioSleep;
+    use aws_smithy_async::rt::sleep::{SharedAsyncSleep, TokioSleep};
     use aws_smithy_async::test_util::controlled_time_and_sleep;
-    use aws_smithy_async::time::SystemTimeSource;
+    use aws_smithy_async::time::{SharedTimeSource, SystemTimeSource};
     use aws_smithy_types::endpoint::Endpoint;
     use std::sync::atomic::{AtomicUsize, Ordering};
     use std::sync::Arc;
@@ -178,8 +178,8 @@ mod test {
                     SystemTime::now(),
                 ))
             },
-            Arc::new(TokioSleep::new()),
-            Arc::new(SystemTimeSource::new()),
+            SharedAsyncSleep::new(TokioSleep::new()),
+            SharedTimeSource::new(SystemTimeSource::new()),
         )
         .await
         .unwrap();
@@ -204,8 +204,8 @@ mod test {
                     ))
                 }
             },
-            Arc::new(TokioSleep::new()),
-            Arc::new(SystemTimeSource::new()),
+            SharedAsyncSleep::new(TokioSleep::new()),
+            SharedTimeSource::new(SystemTimeSource::new()),
         )
         .await
         .expect("returns an endpoint");
@@ -248,8 +248,8 @@ mod test {
                     ))
                 }
             },
-            Arc::new(sleep.clone()),
-            Arc::new(time.clone()),
+            SharedAsyncSleep::new(sleep.clone()),
+            SharedTimeSource::new(time.clone()),
         )
         .await
         .expect("first load success");

aws/rust-runtime/aws-types/external-types.toml

@@ -1,7 +1,7 @@
 allowed_external_types = [
     "aws_credential_types::cache::CredentialsCache",
     "aws_credential_types::provider::SharedCredentialsProvider",
-    "aws_smithy_async::rt::sleep::AsyncSleep",
+    "aws_smithy_async::rt::sleep::SharedAsyncSleep",
     "aws_smithy_async::time::TimeSource",
     "aws_smithy_async::time::SharedTimeSource",
     "aws_smithy_client::http_connector",