Add lifetimes to async traits that take args by reference

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

@@ -50,7 +50,7 @@ use crate::http_credential_provider::HttpCredentialProvider;
 use crate::provider_config::ProviderConfig;
 use aws_credential_types::provider::{self, error::CredentialsError, future, ProvideCredentials};
 use aws_smithy_http::endpoint::apply_endpoint;
-use aws_smithy_runtime_api::client::dns::{DnsResolver, ResolveDnsError, SharedDnsResolver};
+use aws_smithy_runtime_api::client::dns::{ResolveDns, ResolveDnsError, SharedDnsResolver};
 use aws_smithy_runtime_api::client::http::HttpConnectorSettings;
 use aws_smithy_runtime_api::shared::IntoShared;
 use aws_smithy_types::error::display::DisplayErrorContext;
@@ -272,9 +272,9 @@ impl Builder {
 
     /// Override the DNS resolver used to validate URIs
     ///
-    /// URIs must refer to loopback addresses. The [`DnsResolver`](aws_smithy_runtime_api::client::dns::DnsResolver)
-    /// is used to retrieve IP addresses for a given domain.
-    pub fn dns(mut self, dns: impl DnsResolver + 'static) -> Self {
+    /// URIs must refer to loopback addresses. The [`ResolveDns`](aws_smithy_runtime_api::client::dns::ResolveDns)
+    /// implementation is used to retrieve IP addresses for a given domain.
+    pub fn dns(mut self, dns: impl ResolveDns + 'static) -> Self {
         self.dns = Some(dns.into_shared());
         self
     }
@@ -399,7 +399,7 @@ async fn validate_full_uri(
         Ok(addr) => addr.is_loopback(),
         Err(_domain_name) => {
             let dns = dns.ok_or(InvalidFullUriErrorKind::NoDnsResolver)?;
-            dns.resolve_dns(host.to_owned())
+            dns.resolve_dns(host)
                 .await
                 .map_err(|err| InvalidFullUriErrorKind::DnsLookupFailed(ResolveDnsError::new(err)))?
                 .iter()
@@ -751,16 +751,22 @@ mod test {
         }
     }
 
-    impl DnsResolver for TestDns {
-        fn resolve_dns(&self, name: String) -> DnsFuture {
-            DnsFuture::ready(Ok(self.addrs.get(&name).unwrap_or(&self.fallback).clone()))
+    impl ResolveDns for TestDns {
+        fn resolve_dns<'a>(&'a self, name: &'a str) -> DnsFuture<'a>
+        where
+            Self: 'a,
+        {
+            DnsFuture::ready(Ok(self.addrs.get(name).unwrap_or(&self.fallback).clone()))
         }
     }
 
     #[derive(Debug)]
     struct NeverDns;
-    impl DnsResolver for NeverDns {
-        fn resolve_dns(&self, _name: String) -> DnsFuture {
+    impl ResolveDns for NeverDns {
+        fn resolve_dns<'a>(&'a self, _name: &'a str) -> DnsFuture<'a>
+        where
+            Self: 'a,
+        {
             DnsFuture::new(async {
                 Never::new().await;
                 unreachable!()

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

@@ -524,11 +524,13 @@ struct ImdsEndpointResolver {
 }
 
 impl EndpointResolver for ImdsEndpointResolver {
-    fn resolve_endpoint(&self, _: &EndpointResolverParams) -> EndpointFuture {
-        let this = self.clone();
+    fn resolve_endpoint<'a>(&'a self, _: &'a EndpointResolverParams) -> EndpointFuture<'a>
+    where
+        Self: 'a,
+    {
         EndpointFuture::new(async move {
-            this.endpoint_source
-                .endpoint(this.mode_override)
+            self.endpoint_source
+                .endpoint(self.mode_override.clone())
                 .await
                 .map(|uri| Endpoint::builder().url(uri.to_string()).build())
                 .map_err(|err| err.into())

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

@@ -192,23 +192,22 @@ fn parse_token_response(response: &HttpResponse, now: SystemTime) -> Result<Toke
 }
 
 impl IdentityResolver for TokenResolver {
-    fn resolve_identity(&self, _config_bag: &ConfigBag) -> IdentityFuture {
-        let this = self.clone();
-        IdentityFuture::new(async move {
-            let preloaded_token = this
+    fn resolve_identity<'a>(&'a self, _config_bag: &'a ConfigBag) -> IdentityFuture<'a>
+    where
+        Self: 'a,
+    {
+        IdentityFuture::new(async {
+            let preloaded_token = self
                 .inner
                 .cache
-                .yield_or_clear_if_expired(this.inner.time_source.now())
+                .yield_or_clear_if_expired(self.inner.time_source.now())
                 .await;
             let token = match preloaded_token {
                 Some(token) => Ok(token),
                 None => {
-                    this.inner
+                    self.inner
                         .cache
-                        .get_or_load(|| {
-                            let this = this.clone();
-                            async move { this.get_token().await }
-                        })
+                        .get_or_load(|| async { self.get_token().await })
                         .await
                 }
             }?;

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

@@ -20,7 +20,9 @@ use tokio::sync::oneshot::{Receiver, Sender};
 /// Endpoint reloader
 #[must_use]
 pub struct ReloadEndpoint {
-    loader: Box<dyn Fn() -> BoxFuture<(Endpoint, SystemTime), ResolveEndpointError> + Send + Sync>,
+    loader: Box<
+        dyn Fn() -> BoxFuture<'static, (Endpoint, SystemTime), ResolveEndpointError> + Send + Sync,
+    >,
     endpoint: Arc<Mutex<Option<ExpiringEndpoint>>>,
     error: Arc<Mutex<Option<ResolveEndpointError>>>,
     rx: Receiver<()>,

aws/rust-runtime/aws-runtime/src/identity.rs

@@ -23,7 +23,10 @@ pub mod credentials {
     }
 
     impl IdentityResolver for CredentialsIdentityResolver {
-        fn resolve_identity(&self, _config_bag: &ConfigBag) -> IdentityFuture {
+        fn resolve_identity<'a>(&'a self, _config_bag: &'a ConfigBag) -> IdentityFuture<'a>
+        where
+            Self: 'a,
+        {
             let cache = self.credentials_cache.clone();
             IdentityFuture::new(async move {
                 let credentials = cache.as_ref().provide_cached_credentials().await?;

rust-runtime/aws-smithy-async/src/future/mod.rs

@@ -15,4 +15,4 @@ pub mod rendezvous;
 pub mod timeout;
 
 /// A boxed future that outputs a `Result<T, E>`.
-pub type BoxFuture<T, E> = Pin<Box<dyn Future<Output = Result<T, E>> + Send>>;
+pub type BoxFuture<'a, T, E> = Pin<Box<dyn Future<Output = Result<T, E>> + Send + 'a>>;

rust-runtime/aws-smithy-runtime-api/src/client.rs

@@ -3,28 +3,54 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
+/// Declares a new-type for a future that is returned from an async trait (prior to stable async trait).
+///
+/// To declare a future with a static lifetime:
+/// ```ignore
+/// new_type_future! {
+///     doc = "some rustdoc for the future's struct",
+///     pub struct NameOfFuture<'static, OutputType, ErrorType>;
+/// }
+/// ```
+///
+/// To declare a future with a non-static lifetime:
+/// ```ignore
+/// new_type_future! {
+///     doc = "some rustdoc for the future's struct",
+///     pub struct NameOfFuture<'a, OutputType, ErrorType>;
+/// }
+/// ```
 macro_rules! new_type_future {
     (
-        doc = $type_docs:literal,
-        pub struct $future_name:ident<$output:ty, $err:ty>,
+        #[doc = $type_docs:literal]
+        pub struct $future_name:ident<'static, $output:ty, $err:ty>;
     ) => {
+        new_type_future!(@internal, $type_docs, $future_name, $output, $err, 'static,);
+    };
+    (
+        #[doc = $type_docs:literal]
+        pub struct $future_name:ident<$lifetime:lifetime, $output:ty, $err:ty>;
+    ) => {
+        new_type_future!(@internal, $type_docs, $future_name, $output, $err, $lifetime, <$lifetime>);
+    };
+    (@internal, $type_docs:literal, $future_name:ident, $output:ty, $err:ty, $lifetime:lifetime, $($decl_lifetime:tt)*) => {
         pin_project_lite::pin_project! {
             #[allow(clippy::type_complexity)]
             #[doc = $type_docs]
-            pub struct $future_name {
+            pub struct $future_name$($decl_lifetime)* {
                 #[pin]
                 inner: aws_smithy_async::future::now_or_later::NowOrLater<
                     Result<$output, $err>,
-                    aws_smithy_async::future::BoxFuture<$output, $err>
+                    aws_smithy_async::future::BoxFuture<$lifetime, $output, $err>
                 >,
             }
         }
 
-        impl $future_name {
+        impl$($decl_lifetime)* $future_name$($decl_lifetime)* {
             #[doc = concat!("Create a new `", stringify!($future_name), "` with the given future.")]
             pub fn new<F>(future: F) -> Self
             where
-                F: std::future::Future<Output = Result<$output, $err>> + Send + 'static,
+                F: std::future::Future<Output = Result<$output, $err>> + Send + $lifetime,
             {
                 Self {
                     inner: aws_smithy_async::future::now_or_later::NowOrLater::new(Box::pin(future)),
@@ -38,7 +64,7 @@ macro_rules! new_type_future {
             ")]
             pub fn new_boxed(
                 future: std::pin::Pin<
-                    Box<dyn std::future::Future<Output = Result<$output, $err>> + Send>,
+                    Box<dyn std::future::Future<Output = Result<$output, $err>> + Send + $lifetime>,
                 >,
             ) -> Self {
                 Self {
@@ -54,7 +80,7 @@ macro_rules! new_type_future {
             }
         }
 
-        impl std::future::Future for $future_name {
+        impl$($decl_lifetime)* std::future::Future for $future_name$($decl_lifetime)* {
             type Output = Result<$output, $err>;
 
             fn poll(self: std::pin::Pin<&mut Self>, cx: &mut std::task::Context<'_>) -> std::task::Poll<Self::Output> {

rust-runtime/aws-smithy-runtime-api/src/client/dns.rs

@@ -7,14 +7,10 @@
 
 use crate::box_error::BoxError;
 use crate::impl_shared_conversions;
-use aws_smithy_async::future::now_or_later::NowOrLater;
 use std::error::Error as StdError;
 use std::fmt;
-use std::future::Future;
 use std::net::IpAddr;
-use std::pin::Pin;
 use std::sync::Arc;
-use std::task::{Context, Poll};
 
 /// Error that occurs when failing to perform a DNS lookup.
 #[derive(Debug)]
@@ -43,57 +39,40 @@ impl StdError for ResolveDnsError {
     }
 }
 
-type BoxFuture<T> = aws_smithy_async::future::BoxFuture<T, ResolveDnsError>;
-
-/// New-type for the future returned by the [`DnsResolver`] trait.
-pub struct DnsFuture(NowOrLater<Result<Vec<IpAddr>, ResolveDnsError>, BoxFuture<Vec<IpAddr>>>);
-impl DnsFuture {
-    /// Create a new `DnsFuture`
-    pub fn new(
-        future: impl Future<Output = Result<Vec<IpAddr>, ResolveDnsError>> + Send + 'static,
-    ) -> Self {
-        Self(NowOrLater::new(Box::pin(future)))
-    }
-
-    /// Create a `DnsFuture` that is immediately ready
-    pub fn ready(result: Result<Vec<IpAddr>, ResolveDnsError>) -> Self {
-        Self(NowOrLater::ready(result))
-    }
-}
-impl Future for DnsFuture {
-    type Output = Result<Vec<IpAddr>, ResolveDnsError>;
-
-    fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
-        let mut this = self.as_mut();
-        let inner = Pin::new(&mut this.0);
-        Future::poll(inner, cx)
-    }
+new_type_future! {
+    #[doc = "New-type for the future returned by the [`ResolveDns`] trait."]
+    pub struct DnsFuture<'a, Vec<IpAddr>, ResolveDnsError>;
 }
 
 /// Trait for resolving domain names
-pub trait DnsResolver: fmt::Debug + Send + Sync {
+pub trait ResolveDns: fmt::Debug + Send + Sync {
     /// Asynchronously resolve the given domain name
-    fn resolve_dns(&self, name: String) -> DnsFuture;
+    fn resolve_dns<'a>(&'a self, name: &'a str) -> DnsFuture<'a>
+    where
+        Self: 'a;
 }
 
-/// Shared DNS resolver
+/// Shared instance of [`ResolveDns`].
 #[derive(Clone, Debug)]
-pub struct SharedDnsResolver(Arc<dyn DnsResolver>);
+pub struct SharedDnsResolver(Arc<dyn ResolveDns>);
 
 impl SharedDnsResolver {
     /// Create a new `SharedDnsResolver`.
-    pub fn new(resolver: impl DnsResolver + 'static) -> Self {
+    pub fn new(resolver: impl ResolveDns + 'static) -> Self {
         Self(Arc::new(resolver))
     }
 }
 
-impl DnsResolver for SharedDnsResolver {
-    fn resolve_dns(&self, name: String) -> DnsFuture {
+impl ResolveDns for SharedDnsResolver {
+    fn resolve_dns<'a>(&'a self, name: &'a str) -> DnsFuture<'a>
+    where
+        Self: 'a,
+    {
         self.0.resolve_dns(name)
     }
 }
 
-impl_shared_conversions!(convert SharedDnsResolver from DnsResolver using SharedDnsResolver::new);
+impl_shared_conversions!(convert SharedDnsResolver from ResolveDns using SharedDnsResolver::new);
 
 #[cfg(test)]
 mod tests {
@@ -102,6 +81,6 @@ mod tests {
     #[test]
     fn check_send() {
         fn is_send<T: Send>() {}
-        is_send::<DnsFuture>();
+        is_send::<DnsFuture<'_>>();
     }
 }

rust-runtime/aws-smithy-runtime-api/src/client/endpoint.rs

@@ -14,8 +14,8 @@ use std::fmt;
 use std::sync::Arc;
 
 new_type_future! {
-    doc = "Future for [`EndpointResolver::resolve_endpoint`].",
-    pub struct EndpointFuture<Endpoint, BoxError>,
+    #[doc = "Future for [`EndpointResolver::resolve_endpoint`]."]
+    pub struct EndpointFuture<'a, Endpoint, BoxError>;
 }
 
 /// Parameters originating from the Smithy endpoint ruleset required for endpoint resolution.
@@ -45,7 +45,9 @@ impl Storable for EndpointResolverParams {
 /// Configurable endpoint resolver implementation.
 pub trait EndpointResolver: Send + Sync + fmt::Debug {
     /// Asynchronously resolves an endpoint to use from the given endpoint parameters.
-    fn resolve_endpoint(&self, params: &EndpointResolverParams) -> EndpointFuture;
+    fn resolve_endpoint<'a>(&'a self, params: &'a EndpointResolverParams) -> EndpointFuture<'a>
+    where
+        Self: 'a;
 }
 
 /// Shared endpoint resolver.
@@ -62,7 +64,10 @@ impl SharedEndpointResolver {
 }
 
 impl EndpointResolver for SharedEndpointResolver {
-    fn resolve_endpoint(&self, params: &EndpointResolverParams) -> EndpointFuture {
+    fn resolve_endpoint<'a>(&'a self, params: &'a EndpointResolverParams) -> EndpointFuture<'a>
+    where
+        Self: 'a,
+    {
         self.0.resolve_endpoint(params)
     }
 }

rust-runtime/aws-smithy-runtime-api/src/client/http.rs

@@ -62,8 +62,8 @@ use std::sync::Arc;
 use std::time::Duration;
 
 new_type_future! {
-    doc = "Future for [`HttpConnector::call`].",
-    pub struct HttpConnectorFuture<HttpResponse, ConnectorError>,
+    #[doc = "Future for [`HttpConnector::call`]."]
+    pub struct HttpConnectorFuture<'static, HttpResponse, ConnectorError>;
 }
 
 /// Trait with a `call` function that asynchronously converts a request into a response.

rust-runtime/aws-smithy-runtime-api/src/client/identity.rs

@@ -17,8 +17,8 @@ use std::time::SystemTime;
 pub mod http;
 
 new_type_future! {
-    doc = "Future for [`IdentityResolver::resolve_identity`].",
-    pub struct IdentityFuture<Identity, BoxError>,
+    #[doc = "Future for [`IdentityResolver::resolve_identity`]."]
+    pub struct IdentityFuture<'a, Identity, BoxError>;
 }
 
 /// Resolver for identities.
@@ -34,7 +34,9 @@ new_type_future! {
 /// There is no fallback to other auth schemes in the absence of an identity.
 pub trait IdentityResolver: Send + Sync + Debug {
     /// Asynchronously resolves an identity for a request using the given config.
-    fn resolve_identity(&self, config_bag: &ConfigBag) -> IdentityFuture;
+    fn resolve_identity<'a>(&'a self, config_bag: &'a ConfigBag) -> IdentityFuture<'a>
+    where
+        Self: 'a;
 }
 
 /// Container for a shared identity resolver.
@@ -49,7 +51,10 @@ impl SharedIdentityResolver {
 }
 
 impl IdentityResolver for SharedIdentityResolver {
-    fn resolve_identity(&self, config_bag: &ConfigBag) -> IdentityFuture {
+    fn resolve_identity<'a>(&'a self, config_bag: &'a ConfigBag) -> IdentityFuture<'a>
+    where
+        Self: 'a,
+    {
         self.0.resolve_identity(config_bag)
     }
 }