feat: handle errors in 200 response from S3

Tests/Services/AWSS3Tests/S3ErrorIn200Test.swift

@@ -0,0 +1,55 @@
+// Code generated by smithy-swift-codegen. DO NOT EDIT!
+
+import AWSClientRuntime
+@testable import AWSS3
+import AwsCommonRuntimeKit
+import ClientRuntime
+import SmithyTestUtil
+import XCTest
+
+public class MockHttpClientEngine: HttpClientEngine {
+
+    // Public initializer
+    public init() {}
+
+    func successHttpResponse(request: SdkHttpRequest) -> HttpResponse {
+        let errorResponsePayload = """
+            <Error>
+                <Code>SlowDown</Code>
+                <Message>Please reduce your request rate.</Message>
+                <RequestId>K2H6N7ZGQT6WHCEG</RequestId>
+                <HostId>WWoZlnK4pTjKCYn6eNV7GgOurabfqLkjbSyqTvDMGBaI9uwzyNhSaDhOCPs8paFGye7S6b/AB3A=</HostId>
+            </Error>
+        """
+        return HttpResponse(headers: request.headers, body: ByteStream.data(errorResponsePayload.data(using: .utf8)), statusCode: HttpStatusCode.ok)
+    }
+
+    public func execute(request: SdkHttpRequest) async throws -> HttpResponse {
+        return successHttpResponse(request: request)
+    }
+}
+
+class S3ErrorIn200Test: XCTestCase {
+
+    override class func setUp() {
+        AwsCommonRuntimeKit.CommonRuntimeKit.initialize()
+    }
+
+    /// S3Client throws expected error in response (200) with <Error> tag
+    func testFoundExpectedError() async throws {
+        let config = try await S3Client.S3ClientConfiguration(region: "us-west-2")
+        config.httpClientEngine = MockHttpClientEngine()
+        let client = S3Client(config: config)
+
+        do {
+            // any method on S3Client where the output shape doesnt have a stream
+            _ = try await client.listBuckets(input: .init())
+            XCTFail("Expected an error to be thrown, but it was not.")
+        } catch let error as UnknownAWSHTTPServiceError {
+            // check for the error we added in our mock client
+            XCTAssertEqual("Please reduce your request rate.", error.message)
+        } catch {
+            XCTFail("Unexpected error: \(error)")
+        }
+    }
+}

codegen/smithy-aws-swift-codegen/src/main/kotlin/software/amazon/smithy/aws/swift/codegen/customization/s3/S3ErrorWith200StatusIntegration.kt

@@ -0,0 +1,93 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+package software.amazon.smithy.aws.swift.codegen.customization.s3
+
+import software.amazon.smithy.model.Model
+import software.amazon.smithy.model.shapes.OperationShape
+import software.amazon.smithy.model.shapes.ServiceShape
+import software.amazon.smithy.model.traits.StreamingTrait
+import software.amazon.smithy.swift.codegen.ClientRuntimeTypes
+import software.amazon.smithy.swift.codegen.SwiftSettings
+import software.amazon.smithy.swift.codegen.SwiftWriter
+import software.amazon.smithy.swift.codegen.integration.ProtocolGenerator
+import software.amazon.smithy.swift.codegen.integration.SwiftIntegration
+import software.amazon.smithy.swift.codegen.integration.middlewares.handlers.MiddlewareShapeUtils
+import software.amazon.smithy.swift.codegen.middleware.MiddlewarePosition
+import software.amazon.smithy.swift.codegen.middleware.MiddlewareRenderable
+import software.amazon.smithy.swift.codegen.middleware.MiddlewareStep
+import software.amazon.smithy.swift.codegen.middleware.OperationMiddleware
+import software.amazon.smithy.swift.codegen.model.expectShape
+import software.amazon.smithy.swift.codegen.model.hasTrait
+
+/**
+ * Register interceptor to handle S3 error responses returned with an HTTP 200 status code.
+ * see [aws-sdk-kotlin#199](https://github.com/awslabs/aws-sdk-kotlin/issues/199)
+ * see [aws-sdk-swift#1113](https://github.com/awslabs/aws-sdk-swift/issues/1113)
+ */
+class S3ErrorWith200StatusIntegration : SwiftIntegration {
+    override fun enabledForService(model: Model, settings: SwiftSettings): Boolean =
+        model.expectShape<ServiceShape>(settings.service).isS3
+
+    override fun customizeMiddleware(
+        ctx: ProtocolGenerator.GenerationContext,
+        operationShape: OperationShape,
+        operationMiddleware: OperationMiddleware,
+    ) {
+        // we don't know for sure what operations S3 does this on. Go customized this for only a select few
+        // like CopyObject/UploadPartCopy/CompleteMultipartUpload but Rust hit it on additional operations
+        // (DeleteObjects).
+        // Instead of playing whack-a-mole broadly apply this interceptor to everything but streaming responses
+        // which adds a small amount of overhead to response processing.
+        val output = ctx.model.expectShape(operationShape.output.get())
+        val outputIsNotStreaming = output.members().none {
+            it.hasTrait<StreamingTrait>() || ctx.model.expectShape(it.target).hasTrait<StreamingTrait>()
+        }
+        if (outputIsNotStreaming) {
+            operationMiddleware.appendMiddleware(operationShape, S3HandleError200ResponseMiddleware)
+        }
+    }
+}
+
+private object S3HandleError200ResponseMiddleware : MiddlewareRenderable {
+    override val name = "S3ErrorWith200StatusXMLMiddleware"
+
+    override val middlewareStep = MiddlewareStep.DESERIALIZESTEP
+
+    override val position = MiddlewarePosition.AFTER
+
+    override fun render(ctx: ProtocolGenerator.GenerationContext, writer: SwiftWriter, op: OperationShape, operationStackName: String) {
+        val outputShape = MiddlewareShapeUtils.outputSymbol(ctx.symbolProvider, ctx.model, op)
+        writer.openBlock(
+            "$operationStackName.${middlewareStep.stringValue()}.intercept(position: ${position.stringValue()}, id: \"${name}\") { (context, input, next) -> \$N<${outputShape.name}> in",
+            "}",
+            ClientRuntimeTypes.Middleware.OperationOutput,
+        ) {
+            writer.apply {
+                // Send the request and get the response
+                write("let response = try await next.handle(context: context, input: input)")
+
+                // Check if the response status is 200
+                write("guard response.httpResponse.statusCode == .ok else {")
+                write("    return try await next.handle(context: context, input: input)")
+                write("}")
+
+                // Read the response body
+                write("guard let data = try await response.httpResponse.body.readData() else {")
+                write("    return try await next.handle(context: context, input: input)")
+                write("}")
+                write("let xmlString = String(data: data, encoding: .utf8) ?? \"\"")
+
+                // Check for <Error> tag in the XML
+                write("if xmlString.contains(\"<Error>\") {")
+                write("    // Handle the error as a 500 Internal Server Error")
+                write("    response.httpResponse.statusCode = .internalServerError")
+                write("    return response")
+                write("}")
+
+                write("return try await next.handle(context: context, input: input)")
+            }
+        }
+    }
+}

codegen/smithy-aws-swift-codegen/src/main/resources/META-INF/services/software.amazon.smithy.swift.codegen.integration.SwiftIntegration

@@ -1,5 +1,6 @@
 software.amazon.smithy.aws.swift.codegen.AddProtocols
 software.amazon.smithy.aws.swift.codegen.customization.s3.S3ErrorIntegration
+software.amazon.smithy.aws.swift.codegen.customization.s3.S3ErrorWith200StatusIntegration
 software.amazon.smithy.aws.swift.codegen.customization.s3.S3Expires
 software.amazon.smithy.aws.swift.codegen.customization.s3.TruncatablePaginationIntegration
 software.amazon.smithy.aws.swift.codegen.customization.route53.Route53TrimHostedZone