feat: Auth scheme changes

Sources/ClientRuntime/Auth/HTTPAuth/DefaultIdentityResolverConfiguration.swift

@@ -0,0 +1,21 @@
+//
+// Copyright Amazon.com Inc. or its affiliates.
+// All Rights Reserved.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+public struct DefaultIdentityResolverConfiguration: IdentityResolverConfiguration {
+    let credentialsProvider: (any IdentityResolver)?
+
+    public init(configuredIdResolvers: Attributes) {
+        self.credentialsProvider = configuredIdResolvers.get(key: AttributeKeys.awsIdResolver) ?? nil
+    }
+
+    func getIdentityResolver(identityKind: IdentityKind) -> (any IdentityResolver)? {
+        switch identityKind {
+        case .aws:
+            return self.credentialsProvider
+        }
+    }
+}

Sources/ClientRuntime/Auth/HTTPAuthAPI/AuthOption.swift

@@ -0,0 +1,12 @@
+//
+// Copyright Amazon.com Inc. or its affiliates.
+// All Rights Reserved.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+public struct AuthOption {
+    let schemeID: String
+    var identityProperties: Attributes
+    var signingProperties: Attributes
+}

Sources/ClientRuntime/Auth/HTTPAuthAPI/AuthScheme.swift

@@ -0,0 +1,18 @@
+//
+// Copyright Amazon.com Inc. or its affiliates.
+// All Rights Reserved.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+public protocol AuthScheme {
+    var schemeID: String { get }
+    var signer: Signer { get }
+    var idKind: IdentityKind { get }
+}
+
+extension AuthScheme {
+    func identityResolver(config: IdentityResolverConfiguration) -> (any IdentityResolver)? {
+        return config.getIdentityResolver(identityKind: self.idKind)
+    }
+}

Sources/ClientRuntime/Auth/HTTPAuthAPI/AuthSchemeResolver.swift

@@ -0,0 +1,11 @@
+//
+// Copyright Amazon.com Inc. or its affiliates.
+// All Rights Reserved.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+public protocol AuthSchemeResolver {
+    func resolveAuthScheme(params: AuthSchemeResolverParameters) -> [AuthOption]
+    func constructParameters(context: HttpContext) throws -> AuthSchemeResolverParameters
+}

Sources/ClientRuntime/Auth/HTTPAuthAPI/AuthSchemeResolverParameters.swift

@@ -0,0 +1,10 @@
+//
+// Copyright Amazon.com Inc. or its affiliates.
+// All Rights Reserved.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+public protocol AuthSchemeResolverParameters {
+    var operation: String { get }
+}

Sources/ClientRuntime/Auth/HTTPAuthAPI/IdentityResolverConfiguration.swift

@@ -0,0 +1,10 @@
+//
+// Copyright Amazon.com Inc. or its affiliates.
+// All Rights Reserved.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+protocol IdentityResolverConfiguration {
+    func getIdentityResolver(identityKind: IdentityKind) -> (any IdentityResolver)?
+}

Sources/ClientRuntime/Auth/HTTPAuthAPI/SelectedAuthScheme.swift

@@ -0,0 +1,13 @@
+//
+// Copyright Amazon.com Inc. or its affiliates.
+// All Rights Reserved.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+public struct SelectedAuthScheme {
+    let schemeID: String
+    let identity: Identity?
+    let signingProperties: Attributes?
+    let signer: Signer?
+}

Sources/ClientRuntime/Auth/HTTPAuthAPI/Signer.swift

@@ -5,8 +5,6 @@
 // SPDX-License-Identifier: Apache-2.0
 //
 
-import Foundation
-
 public protocol Signer {
     func sign<IdentityT: Identity>(
         requestBuilder: SdkHttpRequestBuilder,

Sources/ClientRuntime/Identity/IdentityAPI/Identity.swift

@@ -5,9 +5,17 @@
 // SPDX-License-Identifier: Apache-2.0
 //
 
-import Foundation
-
 // Base protocol for all identity types
 public protocol Identity {
     var expiration: Date? { get }
 }
+
+// Identity v. IdentityT v. IdentityKind
+// - Identity is the protocol that all identity types must conform to.
+// - IdentityT is the associated type / generic type name used by protocols like IdentityResolver and Signer.
+// - IdentityKind is the enum that's used by IdentityResolverConfiguration to return correct kind of identity resolver
+//   for the given auth scheme. E.g., SigV4AuthScheme has idKind field as .aws. And identityResolver method in SigV4AuthScheme
+//   returns an identity resolver that returns identity of type .aws. 
+public enum IdentityKind: CaseIterable {
+    case aws
+}

Sources/ClientRuntime/Identity/IdentityAPI/IdentityResolver.swift

@@ -5,8 +5,6 @@
 // SPDX-License-Identifier: Apache-2.0
 //
 
-import Foundation
-
 // Base protocol for all identity provider types
 public protocol IdentityResolver {
     associatedtype IdentityT: Identity

Sources/ClientRuntime/Networking/Http/HttpContext.swift

@@ -10,6 +10,23 @@ public class HttpContext: MiddlewareContext {
         self.attributes = attributes
     }
 
+    public func toBuilder() -> HttpContextBuilder {
+        let builder = HttpContextBuilder()
+        builder.attributes = self.attributes
+        if let response = self.response {
+            builder.response = response
+        }
+        return builder
+    }
+
+    public func getAuthSchemeResolver() -> AuthSchemeResolver? {
+        return attributes.get(key: AttributeKeys.authSchemeResolver)
+    }
+
+    public func getAuthSchemes() -> Attributes? {
+        return attributes.get(key: AttributeKeys.authSchemes)
+    }
+
     public func getDecoder() -> ResponseDecoder {
         return attributes.get(key: AttributeKeys.decoder)!
     }
@@ -30,8 +47,8 @@ public class HttpContext: MiddlewareContext {
         return attributes.get(key: AttributeKeys.idempotencyTokenGenerator)!
     }
 
-    public func getIdentityResolvers() -> Attributes {
-        return attributes.get(key: AttributeKeys.identityResolvers)!
+    public func getIdentityResolvers() -> Attributes? {
+        return attributes.get(key: AttributeKeys.identityResolvers)
     }
 
     public func getLogger() -> LogAgent? {
@@ -62,6 +79,10 @@ public class HttpContext: MiddlewareContext {
         return attributes.get(key: AttributeKeys.path)!
     }
 
+    public func getSelectedAuthScheme() -> SelectedAuthScheme? {
+        return attributes.get(key: AttributeKeys.selectedAuthScheme)
+    }
+
     public func getServiceName() -> String {
         return attributes.get(key: AttributeKeys.serviceName)!
     }
@@ -93,6 +114,20 @@ public class HttpContextBuilder {
         return self
     }
 
+    @discardableResult
+    public func withAuthSchemeResolver(value: AuthSchemeResolver) -> HttpContextBuilder {
+        self.attributes.set(key: AttributeKeys.authSchemeResolver, value: value)
+        return self
+    }
+
+    @discardableResult
+    public func withAuthScheme(value: AuthScheme) -> HttpContextBuilder {
+        var authSchemes: Attributes = self.attributes.get(key: AttributeKeys.authSchemes) ?? Attributes()
+        authSchemes.set(key: AttributeKey<AuthScheme>(name: "\(value.schemeID)"), value: value)
+        self.attributes.set(key: AttributeKeys.authSchemes, value: authSchemes)
+        return self
+    }
+
     @discardableResult
     public func withDecoder(value: ResponseDecoder) -> HttpContextBuilder {
         self.attributes.set(key: AttributeKeys.decoder, value: value)
@@ -123,6 +158,14 @@ public class HttpContextBuilder {
         return self
     }
 
+    @discardableResult
+    public func withIdentityResolver<T: IdentityResolver>(value: T, type: IdentityKind) -> HttpContextBuilder {
+        var identityResolvers: Attributes = self.attributes.get(key: AttributeKeys.identityResolvers) ?? Attributes()
+        identityResolvers.set(key: AttributeKey<any IdentityResolver>(name: "\(type)"), value: value)
+        self.attributes.set(key: AttributeKeys.identityResolvers, value: identityResolvers)
+        return self
+    }
+
     @discardableResult
     public func withLogger(value: LogAgent) -> HttpContextBuilder {
         self.attributes.set(key: AttributeKeys.logger, value: value)
@@ -165,6 +208,12 @@ public class HttpContextBuilder {
         return self
     }
 
+    @discardableResult
+    public func withSelectedAuthScheme(value: SelectedAuthScheme) -> HttpContextBuilder {
+        self.attributes.set(key: AttributeKeys.selectedAuthScheme, value: value)
+        return self
+    }
+
     @discardableResult
     public func withServiceName(value: String) -> HttpContextBuilder {
         self.attributes.set(key: AttributeKeys.serviceName, value: value)
@@ -177,6 +226,8 @@ public class HttpContextBuilder {
 }
 
 public enum AttributeKeys {
+    public static let authSchemeResolver = AttributeKey<AuthSchemeResolver>(name: "AuthSchemeResolver")
+    public static let authSchemes = AttributeKey<Attributes>(name: "AuthSchemes")
     public static let bidirectionalStreaming = AttributeKey<Bool>(name: "BidirectionalStreaming")
     public static let decoder = AttributeKey<ResponseDecoder>(name: "Decoder")
     public static let encoder = AttributeKey<RequestEncoder>(name: "Encoder")
@@ -193,5 +244,9 @@ public enum AttributeKeys {
     public static let operation = AttributeKey<String>(name: "Operation")
     public static let partitionId = AttributeKey<String>(name: "PartitionID")
     public static let path = AttributeKey<String>(name: "Path")
+    public static let selectedAuthScheme = AttributeKey<SelectedAuthScheme>(name: "SelectedAuthScheme")
     public static let serviceName = AttributeKey<String>(name: "ServiceName")
+
+    // The attribute key used to store a credentials provider configured on service client config onto middleware context.
+    public static let awsIdResolver = AttributeKey<any IdentityResolver>(name: "AWSIDResolver")
 }