feat: Make models Sendable (#829)

Author: jbelkins

Sources/ClientRuntime/Networking/CRTError+Error.swift

@@ -5,12 +5,28 @@
 // SPDX-License-Identifier: Apache-2.0
 //
 
+import class Foundation.NSRecursiveLock
+
 @propertyWrapper
-public class Indirect<T> {
-    public var wrappedValue: Optional<T>
+public final class Indirect<T: Sendable>: @unchecked Sendable {
+    private let lock = NSRecursiveLock()
+    private var _wrappedValue: Optional<T>
+
+    public var wrappedValue: Optional<T> {
+        get {
+            lock.lock()
+            defer { lock.unlock() }
+            return _wrappedValue
+        }
+        set {
+            lock.lock()
+            defer { lock.unlock() }
+            _wrappedValue = newValue
+        }
+    }
 
     public init(wrappedValue: Optional<T>) {
-        self.wrappedValue = wrappedValue
+        self._wrappedValue = wrappedValue
     }
 }
 

Sources/ClientRuntime/PrimitiveTypeExtensions/Indirect.swift

@@ -8,7 +8,7 @@
 import class Foundation.FileHandle
 import struct Foundation.Data
 
-public enum ByteStream {
+public enum ByteStream: Sendable {
     case data(Data?)
     case stream(Stream)
     case noStream

Sources/Smithy/ByteStream.swift

@@ -8,8 +8,9 @@
 import struct Foundation.Data
 import struct Foundation.Date
 
-public protocol SmithyDocument {
+public protocol SmithyDocument: Sendable {
 
+    /// The Smithy type corresponding to the data stored in this document.
     var type: ShapeType { get }
 
     // "as" methods throw if the document doesn't match the requested type.
@@ -116,6 +117,20 @@ public extension SmithyDocument {
 
 extension SmithyDocument {
 
+    /// Compares two `SmithyDocument`-conforming values, checking for equality.
+    ///
+    /// Two `SmithyDocument`s are equal if they have the same type and equal values.
+    ///
+    /// Two Smithy `list` documents are equal if they have equal documents at every index.
+    ///
+    /// Two Smithy `map` documents are equal if they have the same set of keys, and equal values for every key.
+    ///
+    /// - note: Because `SmithyDocument` is a protocol, it cannot conform to `Equatable`; the type-erased
+    /// container type ``Document`` is used to provide Smithy documents with equatability.
+    /// - Parameters:
+    ///   - lhs: The first `SmithyDocument` to compare.
+    ///   - rhs: The second `SmithyDocument` to compare.
+    /// - Returns: `true` if the two `SmithyDocument`s are equal, `false` otherwise.
     public static func isEqual(_ lhs: SmithyDocument, _ rhs: SmithyDocument) -> Bool {
         switch (lhs.type, rhs.type) {
         case (.blob, .blob):

Sources/Smithy/Document/SmithyDocument.swift

@@ -8,7 +8,7 @@
 import struct Foundation.Data
 
 /// Protocol that provides reading data from a stream
-public protocol ReadableStream: AnyObject {
+public protocol ReadableStream: AnyObject, Sendable {
     /// Returns the current position in the stream
     var position: Data.Index { get }
 
@@ -45,7 +45,7 @@ public protocol ReadableStream: AnyObject {
 }
 
 /// Protocol that provides writing data to a stream
-public protocol WriteableStream: AnyObject {
+public protocol WriteableStream: AnyObject, Sendable {
     ///  Writes the contents of `data` to the stream
     /// - Parameter data: data to write
     func write(contentsOf data: Data) throws

Sources/Smithy/Stream.swift

@@ -16,8 +16,8 @@ import class SmithyStreams.BufferedStream
 /// URLSessionHTTPClient streams chunked payloads using this stream type.
 /// CRTClientEngine uses only the reader provided by this type to create chunks, then it
 /// streams them itself.
-public class ChunkedStream {
-    private var inputStream: Stream
+public class ChunkedStream: @unchecked Sendable {
+    private let inputStream: Stream
     private var signingConfig: SigningConfig
     private var previousSignature: String
     private var trailingHeaders: Headers

Sources/SmithyChecksums/ChunkedStream.swift

@@ -12,7 +12,7 @@ import struct Foundation.Data
 import AwsCommonRuntimeKit
 import class SmithyStreams.BufferedStream
 
-public class ValidatingBufferedStream {
+public class ValidatingBufferedStream: @unchecked Sendable {
     private var stream: BufferedStream
     private var checksumAlgorithm: ChecksumAlgorithm
     private var checksum: (any Checksum)

Sources/SmithyChecksums/ValidatingBufferedStream.swift

@@ -11,7 +11,7 @@ import SmithyEventStreamsAuthAPI
 import struct Foundation.Data
 
 /// Stream adapter that encodes input into `Data` objects.
-public class DefaultMessageEncoderStream<Event>: MessageEncoderStream, Stream {
+public class DefaultMessageEncoderStream<Event>: MessageEncoderStream, Stream, @unchecked Sendable {
 
     let stream: AsyncThrowingStream<Event, Error>
     let messageEncoder: MessageEncoder

Sources/SmithyEventStreams/DefaultMessageEncoderStream.swift

@@ -15,11 +15,3 @@ public enum EventStreamError: Error {
     /// This may be due to missing required headers
     case invalidMessage(String)
 }
-
-extension AsyncThrowingStream: Equatable where Element: Equatable {
-
-    public static func == (lhs: AsyncThrowingStream, rhs: AsyncThrowingStream) -> Bool {
-        // TODO: Remove as part of https://github.com/awslabs/aws-sdk-swift/issues/898
-        return false
-    }
-}

Sources/SmithyEventStreamsAPI/EventStreamError.swift

@@ -5,7 +5,7 @@
 // SPDX-License-Identifier: Apache-2.0
 //
 
-public struct Headers {
+public struct Headers: Sendable {
     public var headers: [Header] = []
 
     /// Creates an empty instance.
@@ -197,7 +197,7 @@ extension Array where Element == Header {
     }
 }
 
-public struct Header {
+public struct Header: Sendable {
     public var name: String
     public var value: [String]