Fix KMS tests by fixing Send bound on fluent send method (#2695)

## Motivation and Context
This PR fixes the KMS tests when the generating code in orchestrator
mode by ensuring the `Future` returned by `send()` implements `Send`,
and also adds a codegen unit test for this so that it's checked at the
generic client level.

----

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

aws/sra-test/integration-tests/aws-sdk-s3/tests/sra_test.rs

@@ -50,6 +50,7 @@ async fn sra_test() {
     conn.full_validate(MediaType::Xml).await.expect("failed")
 }
 
+#[derive(Debug)]
 struct FixupPlugin {
     timestamp: SystemTime,
 }

codegen-client/src/main/kotlin/software/amazon/smithy/rust/codegen/client/smithy/generators/ServiceRuntimePluginGenerator.kt

@@ -90,6 +90,7 @@ class ServiceRuntimePluginGenerator(
     fun render(writer: RustWriter, customizations: List<ServiceRuntimePluginCustomization>) {
         writer.rustTemplate(
             """
+            ##[derive(Debug)]
             pub(crate) struct ServiceRuntimePlugin {
                 handle: std::sync::Arc<crate::client::Handle>,
             }

codegen-client/src/main/kotlin/software/amazon/smithy/rust/codegen/client/smithy/generators/client/FluentClientGenerator.kt

@@ -366,13 +366,13 @@ class FluentClientGenerator(
                     """
                     ##[doc(hidden)]
                     pub async fn send_orchestrator(self) -> std::result::Result<#{OperationOutput}, #{SdkError}<#{OperationError}, #{HttpResponse}>> {
-                        self.send_orchestrator_with_plugin(Option::<Box<dyn #{RuntimePlugin}>>::None).await
+                        self.send_orchestrator_with_plugin(Option::<Box<dyn #{RuntimePlugin} + Send + Sync>>::None).await
                     }
 
                     ##[doc(hidden)]
                     // TODO(enableNewSmithyRuntime): Delete when unused
                     /// Equivalent to [`Self::send_orchestrator`] but adds a final runtime plugin to shim missing behavior
-                    pub async fn send_orchestrator_with_plugin(self, final_plugin: Option<impl #{RuntimePlugin} + 'static>) -> std::result::Result<#{OperationOutput}, #{SdkError}<#{OperationError}, #{HttpResponse}>> {
+                    pub async fn send_orchestrator_with_plugin(self, final_plugin: Option<impl #{RuntimePlugin} + Send + Sync + 'static>) -> std::result::Result<#{OperationOutput}, #{SdkError}<#{OperationError}, #{HttpResponse}>> {
                         let mut runtime_plugins = #{RuntimePlugins}::new()
                             .with_client_plugin(crate::config::ServiceRuntimePlugin::new(self.handle.clone()));
                         if let Some(config_override) = self.config_override {

codegen-client/src/test/kotlin/software/amazon/smithy/rust/codegen/client/smithy/customizations/HttpAuthDecoratorTest.kt

@@ -6,26 +6,16 @@
 package software.amazon.smithy.rust.codegen.client.smithy.customizations
 
 import org.junit.jupiter.api.Test
-import software.amazon.smithy.model.node.ObjectNode
-import software.amazon.smithy.model.node.StringNode
+import software.amazon.smithy.rust.codegen.client.testutil.TestCodegenSettings
 import software.amazon.smithy.rust.codegen.client.testutil.clientIntegrationTest
 import software.amazon.smithy.rust.codegen.core.rustlang.Attribute
 import software.amazon.smithy.rust.codegen.core.rustlang.CargoDependency
 import software.amazon.smithy.rust.codegen.core.rustlang.rustTemplate
 import software.amazon.smithy.rust.codegen.core.smithy.RuntimeConfig
 import software.amazon.smithy.rust.codegen.core.smithy.RuntimeType
-import software.amazon.smithy.rust.codegen.core.testutil.IntegrationTestParams
 import software.amazon.smithy.rust.codegen.core.testutil.asSmithyModel
 import software.amazon.smithy.rust.codegen.core.testutil.integrationTest
 
-private fun additionalSettings(): ObjectNode = ObjectNode.objectNodeBuilder()
-    .withMember(
-        "codegen",
-        ObjectNode.objectNodeBuilder()
-            .withMember("enableNewSmithyRuntime", StringNode.from("orchestrator")).build(),
-    )
-    .build()
-
 class HttpAuthDecoratorTest {
     private fun codegenScope(runtimeConfig: RuntimeConfig): Array<Pair<String, Any>> = arrayOf(
         "TestConnection" to CargoDependency.smithyClient(runtimeConfig)
@@ -38,7 +28,7 @@ class HttpAuthDecoratorTest {
     fun multipleAuthSchemesSchemeSelection() {
         clientIntegrationTest(
             TestModels.allSchemes,
-            IntegrationTestParams(additionalSettings = additionalSettings()),
+            TestCodegenSettings.orchestratorModeTestParams,
         ) { codegenContext, rustCrate ->
             rustCrate.integrationTest("tests") {
                 val moduleName = codegenContext.moduleUseName()
@@ -117,7 +107,7 @@ class HttpAuthDecoratorTest {
     fun apiKeyInQueryString() {
         clientIntegrationTest(
             TestModels.apiKeyInQueryString,
-            IntegrationTestParams(additionalSettings = additionalSettings()),
+            TestCodegenSettings.orchestratorModeTestParams,
         ) { codegenContext, rustCrate ->
             rustCrate.integrationTest("api_key_applied_to_query_string") {
                 val moduleName = codegenContext.moduleUseName()
@@ -162,7 +152,7 @@ class HttpAuthDecoratorTest {
     fun apiKeyInHeaders() {
         clientIntegrationTest(
             TestModels.apiKeyInHeaders,
-            IntegrationTestParams(additionalSettings = additionalSettings()),
+            TestCodegenSettings.orchestratorModeTestParams,
         ) { codegenContext, rustCrate ->
             rustCrate.integrationTest("api_key_applied_to_headers") {
                 val moduleName = codegenContext.moduleUseName()
@@ -208,7 +198,7 @@ class HttpAuthDecoratorTest {
     fun basicAuth() {
         clientIntegrationTest(
             TestModels.basicAuth,
-            IntegrationTestParams(additionalSettings = additionalSettings()),
+            TestCodegenSettings.orchestratorModeTestParams,
         ) { codegenContext, rustCrate ->
             rustCrate.integrationTest("basic_auth") {
                 val moduleName = codegenContext.moduleUseName()
@@ -254,7 +244,7 @@ class HttpAuthDecoratorTest {
     fun bearerAuth() {
         clientIntegrationTest(
             TestModels.bearerAuth,
-            IntegrationTestParams(additionalSettings = additionalSettings()),
+            TestCodegenSettings.orchestratorModeTestParams,
         ) { codegenContext, rustCrate ->
             rustCrate.integrationTest("bearer_auth") {
                 val moduleName = codegenContext.moduleUseName()

codegen-client/src/test/kotlin/software/amazon/smithy/rust/codegen/client/smithy/generators/client/FluentClientGeneratorTest.kt

@@ -0,0 +1,79 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package software.amazon.smithy.rust.codegen.client.smithy.generators.client
+
+import org.junit.jupiter.api.Test
+import software.amazon.smithy.rust.codegen.client.smithy.ClientCodegenContext
+import software.amazon.smithy.rust.codegen.client.testutil.TestCodegenSettings
+import software.amazon.smithy.rust.codegen.client.testutil.clientIntegrationTest
+import software.amazon.smithy.rust.codegen.core.rustlang.CargoDependency
+import software.amazon.smithy.rust.codegen.core.rustlang.rust
+import software.amazon.smithy.rust.codegen.core.rustlang.rustTemplate
+import software.amazon.smithy.rust.codegen.core.rustlang.writable
+import software.amazon.smithy.rust.codegen.core.smithy.RuntimeType
+import software.amazon.smithy.rust.codegen.core.smithy.RustCrate
+import software.amazon.smithy.rust.codegen.core.testutil.asSmithyModel
+import software.amazon.smithy.rust.codegen.core.testutil.integrationTest
+
+class FluentClientGeneratorTest {
+    val model = """
+        namespace com.example
+        use aws.protocols#awsJson1_0
+
+        @awsJson1_0
+        service HelloService {
+            operations: [SayHello],
+            version: "1"
+        }
+
+        operation SayHello { input: TestInput }
+        structure TestInput {}
+    """.asSmithyModel()
+
+    @Test
+    fun `send() future implements Send`() {
+        val test: (ClientCodegenContext, RustCrate) -> Unit = { codegenContext, rustCrate ->
+            rustCrate.integrationTest("send_future_is_send") {
+                val moduleName = codegenContext.moduleUseName()
+                rustTemplate(
+                    """
+                    fn check_send<T: Send>(_: T) {}
+
+                    ##[test]
+                    fn test() {
+                        let connector = #{TestConnection}::<#{SdkBody}>::new(Vec::new());
+                        let config = $moduleName::Config::builder()
+                            .endpoint_resolver("http://localhost:1234")
+                            #{set_http_connector}
+                            .build();
+                        let smithy_client = aws_smithy_client::Builder::new()
+                            .connector(connector.clone())
+                            .middleware_fn(|r| r)
+                            .build_dyn();
+                        let client = $moduleName::Client::with_config(smithy_client, config);
+                        check_send(client.say_hello().send());
+                    }
+                    """,
+                    "TestConnection" to CargoDependency.smithyClient(codegenContext.runtimeConfig)
+                        .withFeature("test-util").toType()
+                        .resolve("test_connection::TestConnection"),
+                    "SdkBody" to RuntimeType.sdkBody(codegenContext.runtimeConfig),
+                    "set_http_connector" to writable {
+                        if (codegenContext.smithyRuntimeMode.generateOrchestrator) {
+                            rust(".http_connector(connector.clone())")
+                        }
+                    },
+                )
+            }
+        }
+        clientIntegrationTest(model, TestCodegenSettings.middlewareModeTestParams, test = test)
+        clientIntegrationTest(
+            model,
+            TestCodegenSettings.orchestratorModeTestParams,
+            test = test,
+        )
+    }
+}

codegen-client/src/test/kotlin/software/amazon/smithy/rust/codegen/client/testutil/TestCodegenSettings.kt

@@ -0,0 +1,38 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package software.amazon.smithy.rust.codegen.client.testutil
+
+import software.amazon.smithy.model.node.ObjectNode
+import software.amazon.smithy.model.node.StringNode
+import software.amazon.smithy.rust.codegen.core.testutil.IntegrationTestParams
+
+object TestCodegenSettings {
+    // TODO(enableNewSmithyRuntime): Delete this when removing `enableNewSmithyRuntime` feature gate
+    fun middlewareMode(): ObjectNode = ObjectNode.objectNodeBuilder()
+        .withMember(
+            "codegen",
+            ObjectNode.objectNodeBuilder()
+                .withMember("enableNewSmithyRuntime", StringNode.from("middleware")).build(),
+        )
+        .build()
+
+    // TODO(enableNewSmithyRuntime): Delete this when removing `enableNewSmithyRuntime` feature gate
+    fun orchestratorMode(): ObjectNode = ObjectNode.objectNodeBuilder()
+        .withMember(
+            "codegen",
+            ObjectNode.objectNodeBuilder()
+                .withMember("enableNewSmithyRuntime", StringNode.from("orchestrator")).build(),
+        )
+        .build()
+
+    // TODO(enableNewSmithyRuntime): Delete this when removing `enableNewSmithyRuntime` feature gate
+    val middlewareModeTestParams get(): IntegrationTestParams =
+        IntegrationTestParams(additionalSettings = middlewareMode())
+
+    // TODO(enableNewSmithyRuntime): Delete this when removing `enableNewSmithyRuntime` feature gate
+    val orchestratorModeTestParams get(): IntegrationTestParams =
+        IntegrationTestParams(additionalSettings = orchestratorMode())
+}

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

@@ -67,7 +67,7 @@ impl AuthOptionResolver for Box<dyn AuthOptionResolver> {
 struct HttpAuthSchemesInner {
     schemes: Vec<(AuthSchemeId, Box<dyn HttpAuthScheme>)>,
 }
-#[derive(Debug)]
+#[derive(Clone, Debug)]
 pub struct HttpAuthSchemes {
     inner: Arc<HttpAuthSchemesInner>,
 }

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

@@ -23,7 +23,7 @@ use std::time::SystemTime;
 pub type HttpRequest = http::Request<SdkBody>;
 pub type HttpResponse = http::Response<SdkBody>;
 pub type BoxError = Box<dyn std::error::Error + Send + Sync + 'static>;
-pub type BoxFuture<T> = Pin<Box<dyn StdFuture<Output = Result<T, BoxError>>>>;
+pub type BoxFuture<T> = Pin<Box<dyn StdFuture<Output = Result<T, BoxError>> + Send>>;
 pub type Future<T> = NowOrLater<Result<T, BoxError>, BoxFuture<T>>;
 
 pub trait RequestSerializer: Send + Sync + fmt::Debug {

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

@@ -5,18 +5,20 @@
 
 use crate::client::interceptors::Interceptors;
 use crate::config_bag::ConfigBag;
+use std::fmt::Debug;
 
-pub type BoxError = Box<dyn std::error::Error + Send + Sync + 'static>;
+pub type BoxError = Box<dyn std::error::Error + Send + Sync>;
+pub type BoxRuntimePlugin = Box<dyn RuntimePlugin + Send + Sync>;
 
-pub trait RuntimePlugin {
+pub trait RuntimePlugin: Debug {
     fn configure(
         &self,
         cfg: &mut ConfigBag,
         interceptors: &mut Interceptors,
     ) -> Result<(), BoxError>;
 }
 
-impl RuntimePlugin for Box<dyn RuntimePlugin> {
+impl RuntimePlugin for BoxRuntimePlugin {
     fn configure(
         &self,
         cfg: &mut ConfigBag,
@@ -28,21 +30,27 @@ impl RuntimePlugin for Box<dyn RuntimePlugin> {
 
 #[derive(Default)]
 pub struct RuntimePlugins {
-    client_plugins: Vec<Box<dyn RuntimePlugin>>,
-    operation_plugins: Vec<Box<dyn RuntimePlugin>>,
+    client_plugins: Vec<BoxRuntimePlugin>,
+    operation_plugins: Vec<BoxRuntimePlugin>,
 }
 
 impl RuntimePlugins {
     pub fn new() -> Self {
         Default::default()
     }
 
-    pub fn with_client_plugin(mut self, plugin: impl RuntimePlugin + 'static) -> Self {
+    pub fn with_client_plugin(
+        mut self,
+        plugin: impl RuntimePlugin + Send + Sync + 'static,
+    ) -> Self {
         self.client_plugins.push(Box::new(plugin));
         self
     }
 
-    pub fn with_operation_plugin(mut self, plugin: impl RuntimePlugin + 'static) -> Self {
+    pub fn with_operation_plugin(
+        mut self,
+        plugin: impl RuntimePlugin + Send + Sync + 'static,
+    ) -> Self {
         self.operation_plugins.push(Box::new(plugin));
         self
     }
@@ -78,6 +86,7 @@ mod tests {
     use crate::client::interceptors::Interceptors;
     use crate::config_bag::ConfigBag;
 
+    #[derive(Debug)]
     struct SomeStruct;
 
     impl RuntimePlugin for SomeStruct {

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

@@ -262,6 +262,7 @@ mod tests {
         )
     }
 
+    #[derive(Debug)]
     struct TestOperationRuntimePlugin;
 
     impl RuntimePlugin for TestOperationRuntimePlugin {
@@ -310,6 +311,7 @@ mod tests {
                 }
             }
 
+            #[derive(Debug)]
             struct FailingInterceptorsOperationRuntimePlugin;
 
             impl RuntimePlugin for FailingInterceptorsOperationRuntimePlugin {

rust-runtime/aws-smithy-runtime/src/client/runtime_plugin/anonymous_auth.rs

@@ -29,8 +29,16 @@ const ANONYMOUS_AUTH_SCHEME_ID: AuthSchemeId = AuthSchemeId::new("anonymous");
 /// **The above components will replace any existing ones!** As such, don't use this plugin unless:
 /// - You only need to make anonymous requests, such as when interacting with [Open Data](https://aws.amazon.com/opendata/).
 /// - You're writing orchestrator tests and don't care about authentication.
+#[non_exhaustive]
+#[derive(Debug, Default)]
 pub struct AnonymousAuthRuntimePlugin;
 
+impl AnonymousAuthRuntimePlugin {
+    pub fn new() -> Self {
+        Self
+    }
+}
+
 impl RuntimePlugin for AnonymousAuthRuntimePlugin {
     fn configure(
         &self,