feat: Add WaiterTypedError type, conform operation errors to it (#491)

Packages/ClientRuntime/Sources/Networking/Http/UnknownHttpServiceError.swift

@@ -5,6 +5,8 @@
 
 /// General Service Error structure used when exact error could not be deduced from the `HttpResponse`
 public struct UnknownHttpServiceError: HttpServiceError, Swift.Equatable {
+    public var _errorType: String?
+
     public var _isThrottling: Bool = false
 
     public var _statusCode: HttpStatusCode?
@@ -19,9 +21,24 @@ public struct UnknownHttpServiceError: HttpServiceError, Swift.Equatable {
 }
 
 extension UnknownHttpServiceError {
-    public init(httpResponse: HttpResponse, message: String? = nil) {
+
+
+    /// Creates an `UnknownHttpServiceError` from a HTTP response.
+    /// - Parameters:
+    ///   - httpResponse: The `HttpResponse` for this error.
+    ///   - message: The message associated with this error. Defaults to `nil`.
+    ///   - errorType: The error type associated with this error.  Defaults to `nil`.
+    public init(httpResponse: HttpResponse, message: String? = nil, errorType: String? = nil) {
         self._statusCode = httpResponse.statusCode
         self._headers = httpResponse.headers
         self._message = message
+        self._errorType = errorType
     }
 }
+
+extension UnknownHttpServiceError: WaiterTypedError {
+
+    /// The Smithy identifier, without namespace, for the type of this error, or `nil` if the
+    /// error has no known type.
+    public var waiterErrorType: String? { _errorType }
+}

Packages/ClientRuntime/Sources/Networking/SdkError.swift

@@ -14,3 +14,19 @@ public enum SdkError<E>: Error {
   case unknown(Error?)
 
 }
+
+extension SdkError: WaiterTypedError {
+
+    /// The Smithy identifier, without namespace, for the type of this error, or `nil` if the
+    /// error has no known type.
+    public var waiterErrorType: String? {
+        switch self {
+        case .service(let error, _):
+            return (error as? WaiterTypedError)?.waiterErrorType
+        case .client(let error, _):
+            return (error as? WaiterTypedError)?.waiterErrorType
+        case .unknown(let error):
+            return (error as? WaiterTypedError)?.waiterErrorType
+        }
+    }
+}

Packages/ClientRuntime/Sources/Waiters/WaiterTypedError.swift

@@ -0,0 +1,16 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0.
+ */
+
+import Foundation
+
+/// An error that may be identified by a string error type, for the purpose of matching the error to a Smithy `errorType` acceptor.
+/// This protocol will only be extended onto errors that have a Smithy waiter defined for them, and is only intended for use in the
+/// operation of a waiter.
+public protocol WaiterTypedError: Error {
+
+    /// The Smithy identifier, without namespace, for the type of this error, or `nil` if the
+    /// error has no known type.
+    var waiterErrorType: String? { get }
+}

smithy-swift-codegen/src/main/kotlin/software/amazon/smithy/swift/codegen/integration/httpResponse/HttpResponseBindingErrorNarrowGenerator.kt

@@ -58,7 +58,7 @@ class HttpResponseBindingErrorNarrowGenerator(
                             var errorShapeEnumCase = errorShapeType.decapitalize()
                             writer.write("case \$S : self = .\$L(try \$L(httpResponse: httpResponse, decoder: decoder, message: message, requestID: requestID))", errorShapeName, errorShapeEnumCase, errorShapeType)
                         }
-                        writer.write("default : self = .unknown($unknownServiceErrorType(httpResponse: httpResponse, message: message, requestID: requestID))")
+                        writer.write("default : self = .unknown($unknownServiceErrorType(httpResponse: httpResponse, message: message, requestID: requestID, errorType: errorType))")
                         writer.write("}")
                     }
                 }

smithy-swift-codegen/src/main/kotlin/software/amazon/smithy/swift/codegen/integration/httpResponse/HttpResponseGenerator.kt

@@ -36,6 +36,7 @@ class HttpResponseGenerator(
         httpOperations.forEach {
             httpResponseBindingErrorGenerator.render(ctx, it)
             HttpResponseBindingErrorNarrowGenerator(ctx, it, unknownServiceErrorSymbol).render()
+            WaiterTypedErrorGenerator(ctx, it, unknownServiceErrorSymbol).render()
         }
 
         val modeledErrors = httpOperations.flatMap { it.errors }.map { ctx.model.expectShape(it) as StructureShape }.toSet()

smithy-swift-codegen/src/main/kotlin/software/amazon/smithy/swift/codegen/integration/httpResponse/WaiterTypedErrorGenerator.kt

@@ -0,0 +1,74 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0.
+ */
+
+package software.amazon.smithy.swift.codegen.integration.httpResponse
+
+import software.amazon.smithy.aws.traits.protocols.AwsQueryErrorTrait
+import software.amazon.smithy.codegen.core.Symbol
+import software.amazon.smithy.model.shapes.OperationShape
+import software.amazon.smithy.model.shapes.StructureShape
+import software.amazon.smithy.swift.codegen.SwiftDependency
+import software.amazon.smithy.swift.codegen.declareSection
+import software.amazon.smithy.swift.codegen.integration.ProtocolGenerator
+import software.amazon.smithy.swift.codegen.integration.SectionId
+import software.amazon.smithy.swift.codegen.integration.middlewares.handlers.MiddlewareShapeUtils
+import software.amazon.smithy.swift.codegen.model.getTrait
+
+class WaiterTypedErrorGenerator(
+    val ctx: ProtocolGenerator.GenerationContext,
+    val op: OperationShape,
+    val unknownServiceErrorSymbol: Symbol
+) {
+    object WaiterTypedErrorGeneratorSectionId : SectionId
+
+    fun render() {
+        val errorShapes = op.errors.map { ctx.model.expectShape(it) as StructureShape }.toSet().sorted()
+        val operationErrorName = MiddlewareShapeUtils.outputErrorSymbolName(op)
+        val rootNamespace = ctx.settings.moduleName
+        val httpBindingSymbol = Symbol.builder()
+            .definitionFile("./$rootNamespace/models/$operationErrorName+WaiterTypedError.swift")
+            .name(operationErrorName)
+            .build()
+
+        ctx.delegator.useShapeWriter(httpBindingSymbol) { writer ->
+            writer.addImport(SwiftDependency.CLIENT_RUNTIME.target)
+            writer.addImport(unknownServiceErrorSymbol)
+            val unknownServiceErrorType = unknownServiceErrorSymbol.name
+
+            val context = mapOf(
+                "ctx" to ctx,
+                "unknownServiceErrorType" to unknownServiceErrorType,
+                "operationErrorName" to operationErrorName,
+                "errorShapes" to errorShapes
+            )
+            writer.declareSection(WaiterTypedErrorGeneratorSectionId, context) {
+                writer.openBlock("extension \$L: WaiterTypedError {", "}", operationErrorName) {
+                    writer.write("")
+                    writer.write("/// The Smithy identifier, without namespace, for the type of this error, or `nil` if the")
+                    writer.write("/// error has no known type.")
+                    writer.openBlock("public var waiterErrorType: String? {", "}") {
+                        writer.write("switch self {")
+                        for (errorShape in errorShapes) {
+                            var errorShapeName = resolveErrorShapeName(errorShape)
+                            var errorShapeType = ctx.symbolProvider.toSymbol(errorShape).name
+                            var errorShapeEnumCase = errorShapeType.decapitalize()
+                            writer.write("case .\$L: return \$S", errorShapeEnumCase, errorShapeName)
+                        }
+                        writer.write("case .unknown(let error): return error.waiterErrorType")
+                        writer.write("}")
+                    }
+                }
+            }
+        }
+    }
+
+    private fun resolveErrorShapeName(errorShape: StructureShape): String {
+        errorShape.getTrait<AwsQueryErrorTrait>()?.let {
+            return it.code
+        } ?: run {
+            return ctx.symbolProvider.toSymbol(errorShape).name
+        }
+    }
+}

smithy-swift-codegen/src/test/kotlin/WaiterTypedErrorGeneratorTests.kt

@@ -0,0 +1,39 @@
+import io.kotest.matchers.string.shouldContainOnlyOnce
+import org.junit.jupiter.api.Test
+import software.amazon.smithy.swift.codegen.ClientRuntimeTypes
+import software.amazon.smithy.swift.codegen.integration.httpResponse.WaiterTypedErrorGenerator
+
+class WaiterTypedErrorGeneratorTests {
+
+    @Test
+    fun `renders correct WaiterTypedError extension for operation error`() {
+        val context = setupTests("waiter-typed-error.smithy", "com.test#WaiterTypedErrorTest")
+        val contents = getFileContents(context.manifest, "/WaiterTypedErrorTest/models/GetWidgetOutputError+WaiterTypedError.swift")
+        val expected = """
+        extension GetWidgetOutputError: WaiterTypedError {
+        
+            /// The Smithy identifier, without namespace, for the type of this error, or `nil` if the
+            /// error has no known type.
+            public var waiterErrorType: String? {
+                switch self {
+                case .invalidWidgetError: return "InvalidWidgetError"
+                case .widgetNotFoundError: return "WidgetNotFoundError"
+                case .unknown(let error): return error.waiterErrorType
+                }
+            }
+        }
+        """.trimIndent()
+        contents.shouldContainOnlyOnce(expected)
+    }
+
+    private fun setupTests(smithyFile: String, serviceShapeId: String): TestContext {
+        val context = TestContext.initContextFrom(smithyFile, serviceShapeId, MockHttpRestJsonProtocolGenerator()) { model ->
+            model.defaultSettings(serviceShapeId, "WaiterTypedErrorTest", "2019-12-16", "WaiterTypedErrorTest")
+        }
+        context.generator.generateProtocolClient(context.generationCtx)
+        val operationShape = context.generationCtx.model.operationShapes.first()
+        WaiterTypedErrorGenerator(context.generationCtx, operationShape, ClientRuntimeTypes.Http.UnknownHttpServiceError).render()
+        context.generationCtx.delegator.flushWriters()
+        return context
+    }
+}

smithy-swift-codegen/src/test/resources/waiter-typed-error.smithy

@@ -0,0 +1,32 @@
+$version: "1.0"
+
+namespace com.test
+
+use aws.api#service
+use aws.protocols#restJson1
+
+@service(sdkId: "WaiterTypedErrorTest")
+service WaiterTypedErrorTest {
+    version: "2019-12-16",
+    operations: [GetWidget]
+}
+
+@http(uri: "/GetWidget", method: "GET")
+operation GetWidget {
+    output: GetWidgetOutput
+    errors: [WidgetNotFoundError, InvalidWidgetError]
+}
+
+structure GetWidgetOutput {
+    name: String
+}
+
+@error("client")
+structure WidgetNotFoundError {
+    name: String
+}
+
+@error("client")
+structure InvalidWidgetError {
+    name: String
+}