feat: add codegen wrappers for retries (#331)

Author: ianbotsf

codegen/smithy-aws-kotlin-codegen/src/main/kotlin/aws/sdk/kotlin/codegen/AwsDefaultRetryIntegration.kt

@@ -0,0 +1,39 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0.
+ */
+
+package aws.sdk.kotlin.codegen
+
+import software.amazon.smithy.kotlin.codegen.core.KotlinWriter
+import software.amazon.smithy.kotlin.codegen.core.RuntimeTypes
+import software.amazon.smithy.kotlin.codegen.integration.KotlinIntegration
+import software.amazon.smithy.kotlin.codegen.rendering.protocol.HttpFeatureMiddleware
+import software.amazon.smithy.kotlin.codegen.rendering.protocol.ProtocolGenerator
+import software.amazon.smithy.kotlin.codegen.rendering.protocol.ProtocolMiddleware
+import software.amazon.smithy.kotlin.codegen.rendering.protocol.replace
+import software.amazon.smithy.kotlin.codegen.retries.StandardRetryMiddleware
+
+/**
+ * Adds AWS-specific retry wrappers around operation invocations. This replaces
+ * [StandardRetryPolicy][aws.smithy.kotlin.runtime.retries.impl] with
+ * [AwsDefaultRetryPolicy][aws.sdk.kotlin.runtime.http.retries].
+ */
+class AwsDefaultRetryIntegration : KotlinIntegration {
+    override fun customizeMiddleware(
+        ctx: ProtocolGenerator.GenerationContext,
+        resolved: List<ProtocolMiddleware>
+    ): List<ProtocolMiddleware> = resolved.replace(middleware) { it.name == StandardRetryMiddleware.name }
+}
+
+private val middleware = object : HttpFeatureMiddleware() {
+    override val name: String = "RetryFeature"
+
+    override fun renderConfigure(writer: KotlinWriter) {
+        writer.addImport(RuntimeTypes.Http.Middlware.RetryFeature)
+        writer.addImport(AwsRuntimeTypes.Http.Retries.AwsDefaultRetryPolicy)
+
+        writer.write("strategy = config.retryStrategy")
+        writer.write("policy = AwsDefaultRetryPolicy")
+    }
+}

codegen/smithy-aws-kotlin-codegen/src/main/kotlin/aws/sdk/kotlin/codegen/AwsRuntimeTypes.kt

@@ -57,6 +57,10 @@ object AwsRuntimeTypes {
     object Http {
         val withPayload = runtimeSymbol("withPayload", AwsKotlinDependency.AWS_HTTP)
         val setAseErrorMetadata = runtimeSymbol("setAseErrorMetadata", AwsKotlinDependency.AWS_HTTP)
+
+        object Retries {
+            val AwsDefaultRetryPolicy = runtimeSymbol("AwsDefaultRetryPolicy", AwsKotlinDependency.AWS_HTTP, "retries")
+        }
     }
 
     object JsonProtocols {

codegen/smithy-aws-kotlin-codegen/src/main/kotlin/aws/sdk/kotlin/codegen/protocols/middleware/MutateHeadersMiddleware.kt

@@ -20,7 +20,7 @@ class MutateHeadersMiddleware(
     override val name: String = "MutateHeaders"
     override val order: Byte = 10
     override fun renderConfigure(writer: KotlinWriter) {
-        writer.addImport(RuntimeTypes.Http.MutateHeadersMiddleware)
+        writer.addImport(RuntimeTypes.Http.Middlware.MutateHeadersMiddleware)
         overrideHeaders.forEach {
             writer.write("set(#S, #S)", it.key, it.value)
         }

codegen/smithy-aws-kotlin-codegen/src/main/resources/META-INF/services/software.amazon.smithy.kotlin.codegen.integration.KotlinIntegration

@@ -1,4 +1,5 @@
 aws.sdk.kotlin.codegen.SdkProtocolGeneratorSupplier
+aws.sdk.kotlin.codegen.AwsDefaultRetryIntegration
 aws.sdk.kotlin.codegen.customization.s3.S3GeneratorSupplier
 aws.sdk.kotlin.codegen.GradleGenerator
 aws.sdk.kotlin.codegen.AwsServiceConfigIntegration
@@ -12,4 +13,4 @@ aws.sdk.kotlin.codegen.customization.apigateway.ApiGatewayAddAcceptHeader
 aws.sdk.kotlin.codegen.customization.glacier.GlacierAddVersionHeader
 aws.sdk.kotlin.codegen.customization.glacier.GlacierAccountIdDefault
 aws.sdk.kotlin.codegen.customization.polly.PollyPresigner
-aws.sdk.kotlin.codegen.customization.BoxServices
+aws.sdk.kotlin.codegen.customization.BoxServices