feat!: Create retry modules

.swiftlint.yml

@@ -2,13 +2,7 @@ excluded:
   - .build
   - Sources/SmithyTestUtil/*
   - Sources/WeatherSDK/*
-  - Tests/ClientRuntimeTests/*
-  - Tests/SmithyTestUtilTests/*
-  - Tests/SmithyXMLTests/*
-  - Tests/SmithyJSONTests/*
-  - Tests/SmithyFormURLTests/*
-  - Tests/SmithyTimestampsTests/*
-  - Tests/WeatherSDKTests/*
+  - Tests/*
   - smithy-swift-codegen-test/build/*
 
 analyzer_rules:

Package.swift

@@ -29,6 +29,8 @@ let package = Package(
     ],
     products: [
         .library(name: "ClientRuntime", targets: ["ClientRuntime"]),
+        .library(name: "SmithyRetriesAPI", targets: ["SmithyRetriesAPI"]),
+        .library(name: "SmithyRetries", targets: ["SmithyRetries"]),
         .library(name: "SmithyReadWrite", targets: ["SmithyReadWrite"]),
         .library(name: "SmithyXML", targets: ["SmithyXML"]),
         .library(name: "SmithyJSON", targets: ["SmithyJSON"]),
@@ -43,6 +45,8 @@ let package = Package(
         .target(
             name: "ClientRuntime",
             dependencies: [
+                "SmithyRetriesAPI",
+                "SmithyRetries",
                 "SmithyXML",
                 "SmithyJSON",
                 "SmithyFormURL",
@@ -53,6 +57,19 @@ let package = Package(
                 .copy("PrivacyInfo.xcprivacy")
             ]
         ),
+        .target(
+            name: "SmithyRetriesAPI"
+        ),
+        .target(
+            name: "SmithyRetries",
+            dependencies: [
+                .product(name: "AwsCommonRuntimeKit", package: "aws-crt-swift"),
+            ]
+        ),
+        .testTarget(
+            name: "SmithyRetriesTests",
+            dependencies: ["ClientRuntime", "SmithyRetriesAPI", "SmithyRetries"]
+        ),
         .target(
             name: "SmithyReadWrite",
             dependencies: [
@@ -121,11 +138,11 @@ func addTestServiceTargets() {
     package.targets += [
         .target(
             name: "WeatherSDK",
-            dependencies: ["SmithyTestUtil", "ClientRuntime"]
+            dependencies: ["SmithyTestUtil", "ClientRuntime", "SmithyRetriesAPI", "SmithyRetries"]
         ),
         .testTarget(
             name: "WeatherSDKTests",
-            dependencies: ["WeatherSDK"]
+            dependencies: ["WeatherSDK", "SmithyTestUtil"]
         )
     ]
 }

Sources/ClientRuntime/Config/DefaultClientConfiguration.swift

@@ -5,6 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0
 //
 
+import struct SmithyRetriesAPI.RetryStrategyOptions
+
 public protocol DefaultClientConfiguration: ClientConfiguration {
     /// The configuration for retry of failed network requests.
     ///

Sources/ClientRuntime/Config/DefaultSDKRuntimeConfiguration.swift

@@ -5,6 +5,12 @@
 // SPDX-License-Identifier: Apache-2.0
 //
 
+import protocol SmithyRetriesAPI.RetryStrategy
+import protocol SmithyRetriesAPI.RetryErrorInfoProvider
+import struct SmithyRetriesAPI.RetryStrategyOptions
+import struct SmithyRetries.DefaultRetryStrategy
+import struct SmithyRetries.ExponentialBackoffStrategy
+
 /// Provides configuration options for a Smithy-based service.
 public struct DefaultSDKRuntimeConfiguration<DefaultSDKRuntimeRetryStrategy: RetryStrategy,
     DefaultSDKRuntimeRetryErrorInfoProvider: RetryErrorInfoProvider> {
@@ -80,7 +86,7 @@
     static func makeClient(
         httpClientConfiguration: HttpClientConfiguration = defaultHttpClientConfiguration
     ) -> HTTPClient {
         #if os(iOS) || os(tvOS) || os(watchOS) || os(visionOS) || os(macOS)
         return URLSessionHTTPClient(httpClientConfiguration: httpClientConfiguration)
         #else
         let connectTimeoutMs = httpClientConfiguration.connectTimeout.map { UInt32($0 * 1000) }
@@ -107,7 +113,9 @@
     /// The retry strategy options to use when none is provided.
     ///
     /// Defaults to options with the defaults defined in `RetryStrategyOptions`.
-    static var defaultRetryStrategyOptions: RetryStrategyOptions { RetryStrategyOptions() }
+    static var defaultRetryStrategyOptions: RetryStrategyOptions {
+        RetryStrategyOptions(backoffStrategy: ExponentialBackoffStrategy())
+    }
 
     /// The log mode to use when none is provided
     ///

Sources/ClientRuntime/Middleware/RetryMiddleware.swift

@@ -10,6 +10,9 @@
 import struct Foundation.TimeInterval
 import struct Foundation.TimeZone
 import struct Foundation.UUID
+import protocol SmithyRetriesAPI.RetryStrategy
+import protocol SmithyRetriesAPI.RetryErrorInfoProvider
+import struct SmithyRetriesAPI.RetryStrategyOptions
 
 public struct RetryMiddleware<Strategy: RetryStrategy,
                               ErrorInfoProvider: RetryErrorInfoProvider,
@@ -64,17 +67,15 @@
                 context.getLogger()?.error("Failed to refresh retry token: \(errorInfo.errorType)")
                 throw operationError
             }
-            var estimatedSkew = context.attributes.get(key: AttributeKeys.estimatedSkew)
-            if estimatedSkew == nil {
-                estimatedSkew = 0
+            var estimatedSkew = context.attributes.get(key: AttributeKeys.estimatedSkew) ?? {
                 context.getLogger()?.info("Estimated skew not found; defaulting to zero.")
-            }
-            var socketTimeout = context.attributes.get(key: AttributeKeys.socketTimeout)
-            if socketTimeout == nil {
-                socketTimeout = 60.0
+                return 0
+            }()
+            var socketTimeout = context.attributes.get(key: AttributeKeys.socketTimeout) ?? {
                 context.getLogger()?.info("Socket timeout value not found; defaulting to 60 seconds.")
-            }
-            let ttlDateUTCString = getTTL(now: Date(), estimatedSkew: estimatedSkew!, socketTimeout: socketTimeout!)
+                return 60.0
+            }()
+            let ttlDateUTCString = getTTL(now: Date(), estimatedSkew: estimatedSkew, socketTimeout: socketTimeout)
             input.headers.update(
                 name: "amz-sdk-request",
                 value: "ttl=\(ttlDateUTCString); attempt=\(attemptNumber + 1); max=\(maxRetries)"

Sources/ClientRuntime/Orchestrator/Orchestrator.swift

@@ -5,6 +5,9 @@
 // SPDX-License-Identifier: Apache-2.0
 //
 
+import protocol SmithyRetriesAPI.RetryStrategy
+import struct SmithyRetriesAPI.RetryErrorInfo
+
 /// Orchestrates operation execution
 ///
 /// Execution performs the following steps in order:

Sources/ClientRuntime/Orchestrator/OrchestratorBuilder.swift

@@ -5,6 +5,9 @@
 // SPDX-License-Identifier: Apache-2.0
 //
 
+import protocol SmithyRetriesAPI.RetryStrategy
+import struct SmithyRetriesAPI.RetryErrorInfo
+
 /// Builds an Orchestrator, combining runtime components, interceptors, serializers, and deserializers.
 ///
 /// Note: This is intended to be used within generated code, not directly.

Sources/ClientRuntime/Plugins/DefaultClientPlugin.swift

@@ -5,6 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0
 //
 
+import struct SmithyRetries.DefaultRetryStrategy
+
 public class DefaultClientPlugin: Plugin {
     public init() {}
     public func configureClient(clientConfiguration: ClientConfiguration) {

Sources/ClientRuntime/Plugins/HttpClientPlugin.swift

@@ -5,6 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0
 //
 
+import struct SmithyRetries.DefaultRetryStrategy
+
 public class DefaultHttpClientPlugin: Plugin {
 
     var httpClientConfiguration: HttpClientConfiguration

Sources/ClientRuntime/Plugins/RetryPlugin.swift

@@ -5,6 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0
 //
 
+import struct SmithyRetriesAPI.RetryStrategyOptions
+
 public class RetryPlugin: Plugin {
 
     private var retryStrategyOptions: RetryStrategyOptions

Sources/ClientRuntime/Retries/DefaultRetryErrorInfoProvider.swift

@@ -6,6 +6,9 @@
 //
 
 import struct Foundation.TimeInterval
+import struct SmithyRetriesAPI.RetryErrorInfo
+import enum SmithyRetriesAPI.RetryErrorType
+import protocol SmithyRetriesAPI.RetryErrorInfoProvider
 
 public enum DefaultRetryErrorInfoProvider: RetryErrorInfoProvider {
 

Sources/SmithyRetries/DefaultRetryStrategy/DefaultRetryStrategy+Error.swift

@@ -0,0 +1,19 @@
+//
+// Copyright Amazon.com Inc. or its affiliates.
+// All Rights Reserved.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+public extension DefaultRetryStrategy {
+
+    /// Errors that may be thrown when an operation is retried unsuccessfully.
+    enum Error: Swift.Error {
+
+        /// The number and frequency of retries being attempted has exceeded the
+        /// current limits.
+        ///
+        /// This error is only raised when the `adaptive` rate limiting mode of retry is used.
+        case insufficientQuota
+    }
+}

Sources/ClientRuntime/Retries/DefaultRetryStrategy/DefaultRetryStrategy.swift → Sources/SmithyRetries/DefaultRetryStrategy/DefaultRetryStrategy.swift

@@ -6,6 +6,10 @@
 //
 
 import struct Foundation.TimeInterval
+import protocol SmithyRetriesAPI.RetryStrategy
+import struct SmithyRetriesAPI.RetryStrategyOptions
+import struct SmithyRetriesAPI.RetryErrorInfo
+import enum SmithyRetriesAPI.RetryError
 
 public struct DefaultRetryStrategy: RetryStrategy {
     public typealias Token = DefaultRetryToken
@@ -43,7 +47,7 @@ public struct DefaultRetryStrategy: RetryStrategy {
         if let capacityAmount = await tokenToRenew.quota.hasRetryQuota(isTimeout: errorInfo.isTimeout) {
             tokenToRenew.capacityAmount = capacityAmount
         } else {
-            throw RetryError.insufficientQuota
+            throw Error.insufficientQuota
         }
         let isThrottling = errorInfo.errorType == .throttling
         await tokenToRenew.quota.updateClientSendingRate(isThrottling: isThrottling)
@@ -55,8 +59,3 @@ public struct DefaultRetryStrategy: RetryStrategy {
         await token.quota.retryQuotaRelease(isSuccess: true, capacityAmount: token.capacityAmount)
     }
 }
-
-enum RetryError: Error {
-    case maxAttemptsReached
-    case insufficientQuota
-}

Sources/ClientRuntime/Retries/DefaultRetryStrategy/DefaultRetryToken.swift → Sources/SmithyRetries/DefaultRetryStrategy/DefaultRetryToken.swift

@@ -6,6 +6,7 @@
 //
 
 import struct Foundation.TimeInterval
+import protocol SmithyRetriesAPI.RetryToken
 
 /// A token that is used to track retry of operations.
 ///

Sources/ClientRuntime/Retries/DefaultRetryStrategy/RetryQuota.swift → Sources/SmithyRetries/DefaultRetryStrategy/RetryQuota.swift

@@ -6,6 +6,7 @@
 //
 
 import struct Foundation.TimeInterval
+import struct SmithyRetriesAPI.RetryStrategyOptions
 
 /// Keeps the retry quota count for one partition ID.
 ///

Sources/ClientRuntime/Retries/DefaultRetryStrategy/RetryQuotaRepository.swift → Sources/SmithyRetries/DefaultRetryStrategy/RetryQuotaRepository.swift

@@ -5,6 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0
 //
 
+import struct SmithyRetriesAPI.RetryStrategyOptions
+
 /// Holds multiple quotas, keyed by partition IDs.
 actor RetryQuotaRepository {
     let options: RetryStrategyOptions

Sources/ClientRuntime/Retries/ExponentialBackoffStrategy.swift → Sources/SmithyRetries/ExponentialBackoffStrategy.swift

@@ -7,6 +7,7 @@
 
 import func Foundation.pow
 import struct Foundation.TimeInterval
+import protocol SmithyRetriesAPI.RetryBackoffStrategy
 
 public struct ExponentialBackoffStrategy: RetryBackoffStrategy {
     let options: ExponentialBackoffStrategyOptions

Sources/SmithyRetries/RetryErrorType+CRT.swift

@@ -0,0 +1,21 @@
+//
+// Copyright Amazon.com Inc. or its affiliates.
+// All Rights Reserved.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+import enum SmithyRetriesAPI.RetryErrorType
+import AwsCommonRuntimeKit
+
+public extension RetryErrorType {
+
+    func toCRTType() -> AwsCommonRuntimeKit.RetryError {
+        switch self {
+        case .transient: return .transient
+        case .throttling: return .throttling
+        case .serverError: return .serverError
+        case .clientError: return .clientError
+        }
+    }
+}

Sources/SmithyRetriesAPI/RetryError.swift

@@ -0,0 +1,14 @@
+//
+// Copyright Amazon.com Inc. or its affiliates.
+// All Rights Reserved.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+/// Errors that may be thrown when an operation is retried unsuccessfully.
+public enum RetryError: Error {
+
+    /// The maximum number of allowed retry attempts were made,
+    /// but the operation could not be successfully completed.
+    case maxAttemptsReached
+}

Sources/ClientRuntime/Retries/RetryErrorInfo.swift → Sources/SmithyRetriesAPI/RetryErrorInfo.swift

@@ -7,6 +7,10 @@
 
 import struct Foundation.TimeInterval
 
+/// A set of information fields that are derived from an error thrown when connecting to a service.
+///
+/// The `RetryErrorInfoProvider` creates an instance of this structure, which is then used by the
+/// `RetryStrategy` to determine whether & how to retry a failed attempt.
 public struct RetryErrorInfo: Equatable {
 
     /// The general nature of the cause of this retryable error.

Sources/ClientRuntime/Retries/RetryErrorType.swift → Sources/SmithyRetriesAPI/RetryErrorType.swift

@@ -4,8 +4,11 @@
 //
 // SPDX-License-Identifier: Apache-2.0
 //
-import AwsCommonRuntimeKit
 
+/// This enum is a general classification that is assigned to errors that resulted from a failed attempt to perform
+/// an operation.
+///
+/// The retry strategy uses this classification to decide whether and when to retry a failed attempt.
 public enum RetryErrorType: Equatable {
 
     /// This is a connection level error such as a socket timeout, socket connect error, tls negotiation timeout etc...
@@ -22,15 +25,3 @@ public enum RetryErrorType: Equatable {
     /// Doesn’t count against any budgets.  This could be something like a 401 challenge in HTTP.
     case clientError
 }
-
-public extension RetryErrorType {
-
-    func toCRTType() -> AwsCommonRuntimeKit.RetryError {
-        switch self {
-        case .transient: return .transient
-        case .throttling: return .throttling
-        case .serverError: return .serverError
-        case .clientError: return .clientError
-        }
-    }
-}

Sources/ClientRuntime/Retries/RetryStrategyOptions.swift → Sources/SmithyRetriesAPI/RetryStrategyOptions.swift

@@ -36,12 +36,12 @@ public struct RetryStrategyOptions {
     /// Sets the initial available capacity for this retry strategy's quotas.
     ///
     /// Used only during testing, production uses the default values.
-    let availableCapacity: Int
+    public let availableCapacity: Int
 
     /// Sets the maximum capacity for this retry strategy's quotas.
     ///
     /// Used only during testing, production uses the default values.
-    let maxCapacity: Int
+    public let maxCapacity: Int
 
     /// Creates a new set of retry strategy options
     /// - Parameters:
@@ -50,7 +50,7 @@ public struct RetryStrategyOptions {
     ///   - availableCapacity: The number of available tokens in a retry quota.  Defaults to 500.
     ///   - maxCapacity: The max number of tokens in a retry quota.  Defaults to 500.
     public init(
-        backoffStrategy: RetryBackoffStrategy = ExponentialBackoffStrategy(),
+        backoffStrategy: RetryBackoffStrategy,
         maxRetriesBase: Int = 2,
         availableCapacity: Int = 500,
         maxCapacity: Int = 500,

Sources/SmithyTestUtil/RequestTestUtil/MockRetryStrategy.swift

@@ -5,6 +5,12 @@
 // SPDX-License-Identifier: Apache-2.0
 //
 
+import protocol SmithyRetriesAPI.RetryStrategy
+import protocol SmithyRetriesAPI.RetryToken
+import struct SmithyRetriesAPI.RetryStrategyOptions
+import struct SmithyRetriesAPI.RetryErrorInfo
+import enum SmithyRetriesAPI.RetryError
+
 @testable import ClientRuntime
 
 public struct MockRetryStrategy: RetryStrategy {