First pass at marking types as Sendable (#450)

Author: domkm

Sources/Internal/JSON.swift

@@ -8,28 +8,32 @@ import Foundation
 
 /// Wraps a dictionary parsed from a JSON string.
 /// This is a trick to keep the Web Publication structs equatable without having to override `==` and compare all the other properties.
-public struct JSONDictionary {
-    public var json: [String: Any]
+public struct JSONDictionary: Sendable {
+    public typealias Key = String
+    public typealias Value = Sendable
+    public typealias Wrapped = [Key: Value]
+
+    public var json: Wrapped
 
     public init() {
         json = [:]
     }
 
     public init?(_ json: Any?) {
-        guard let json = json as? [String: Any] else {
+        guard let json = json as? Wrapped else {
             return nil
         }
         self.json = json
     }
 
-    public mutating func pop(_ key: String) -> Any? {
+    public mutating func pop(_ key: Key) -> Value? {
         json.removeValue(forKey: key)
     }
 }
 
 extension JSONDictionary: Collection {
-    public typealias Index = DictionaryIndex<String, Any>
-    public typealias Element = (key: String, value: Any)
+    public typealias Index = DictionaryIndex<Key, Value>
+    public typealias Element = (key: Key, value: Value)
 
     public var startIndex: Index {
         json.startIndex
@@ -122,7 +126,7 @@ public func parseDate(_ json: Any?) -> Date? {
 
 /// Returns the given JSON object after removing any key with NSNull value.
 /// To be used with `encodeIfX` functions for more compact serialization code.
-public func makeJSON(_ object: [String: Any], additional: [String: Any] = [:]) -> [String: Any] {
+public func makeJSON(_ object: JSONDictionary.Wrapped, additional: JSONDictionary.Wrapped = [:]) -> JSONDictionary.Wrapped {
     object.filter { _, value in
         !(value is NSNull)
     }.merging(additional, uniquingKeysWith: { current, _ in current })

Sources/Shared/Publication/Accessibility.swift

@@ -11,7 +11,7 @@ import ReadiumInternal
 ///
 /// https://www.w3.org/2021/a11y-discov-vocab/latest/
 /// https://readium.org/webpub-manifest/schema/a11y.schema.json
-public struct Accessibility: Hashable {
+public struct Accessibility: Hashable, Sendable {
     /// An established standard to which the described resource conforms.
     public var conformsTo: [Profile]
 
@@ -49,7 +49,7 @@ public struct Accessibility: Hashable {
     public var hazards: [Hazard]
 
     /// Accessibility profile.
-    public struct Profile: Hashable {
+    public struct Profile: Hashable, Sendable {
         public let uri: String
 
         public init(_ uri: String) {
@@ -64,7 +64,7 @@ public struct Accessibility: Hashable {
         public static let epubA11y10WCAG20AAA = Profile("http://www.idpf.org/epub/a11y/accessibility-20170105.html#wcag-aaa")
     }
 
-    public struct Certification: Hashable {
+    public struct Certification: Hashable, Sendable {
         /// Identifies a party responsible for the testing and certification of the accessibility of a Publication.
         ///
         /// https://www.w3.org/TR/epub-a11y/#certifiedBy
@@ -89,7 +89,7 @@ public struct Accessibility: Hashable {
         }
     }
 
-    public struct AccessMode: Hashable {
+    public struct AccessMode: Hashable, Sendable {
         public let id: String
 
         public init(_ id: String) {
@@ -134,7 +134,7 @@ public struct Accessibility: Hashable {
         public static let visual = AccessMode("visual")
     }
 
-    public enum PrimaryAccessMode: String, Hashable {
+    public enum PrimaryAccessMode: String, Hashable, Sendable {
         /// Indicates that auditory perception is necessary to consume the information.
         case auditory
 
@@ -151,7 +151,7 @@ public struct Accessibility: Hashable {
         case visual
     }
 
-    public struct Feature: Hashable {
+    public struct Feature: Hashable, Sendable {
         public let id: String
 
         public init(_ id: String) {
@@ -306,7 +306,7 @@ public struct Accessibility: Hashable {
         public static let none = Feature("none")
     }
 
-    public struct Hazard: Hashable {
+    public struct Hazard: Hashable, Sendable {
         public let id: String
 
         public init(_ id: String) {

Sources/Shared/Publication/Asset/FileAsset.swift

@@ -7,7 +7,7 @@
 import Foundation
 
 /// Represents a publication stored as a file on the local file system.
-public final class FileAsset: PublicationAsset, Loggable {
+public final class FileAsset: PublicationAsset, Loggable, Sendable {
     /// File URL on the file system.
     public let file: FileURL
 

Sources/Shared/Publication/Asset/PublicationAsset.swift

@@ -7,7 +7,7 @@
 import Foundation
 
 /// Represents a digital medium (e.g. a file) offering access to a publication.
-public protocol PublicationAsset {
+public protocol PublicationAsset: Sendable {
     /// Name of the asset, e.g. a filename.
     var name: String { get }
 

Sources/Shared/Publication/Contributor.swift

@@ -8,7 +8,7 @@ import Foundation
 import ReadiumInternal
 
 /// https://readium.org/webpub-manifest/schema/contributor-object.schema.json
-public struct Contributor: Hashable {
+public struct Contributor: Hashable, Sendable {
     /// The name of the contributor.
     public var localizedName: LocalizedString
     public var name: String { localizedName.string }

Sources/Shared/Publication/Link.swift

@@ -14,7 +14,7 @@ public enum LinkError: Error, Equatable {
 
 /// Link Object for the Readium Web Publication Manifest.
 /// https://readium.org/webpub-manifest/schema/link.schema.json
-public struct Link: JSONEquatable, Hashable {
+public struct Link: JSONEquatable, Hashable, Sendable {
     /// URI or URI template of the linked resource.
     /// Note: a String because templates are lost with URL.
     public var href: String // URI
@@ -95,7 +95,7 @@ public struct Link: JSONEquatable, Hashable {
         json: Any,
         warnings: WarningLogger? = nil
     ) throws {
-        guard let jsonObject = json as? [String: Any],
+        guard let jsonObject = json as? JSONDictionary.Wrapped,
               var href = jsonObject["href"] as? String
         else {
             warnings?.log("`href` is required", model: Self.self, source: json)
@@ -132,7 +132,7 @@ public struct Link: JSONEquatable, Hashable {
         )
     }
 
-    public var json: [String: Any] {
+    public var json: JSONDictionary.Wrapped {
         makeJSON([
             "href": href,
             "type": encodeIfNotNil(type),
@@ -252,7 +252,7 @@ public struct Link: JSONEquatable, Hashable {
     }
 
     ///  Merges in the given additional other `properties`.
-    public mutating func addProperties(_ properties: [String: Any]) {
+    public mutating func addProperties(_ properties: JSONDictionary.Wrapped) {
         self.properties.add(properties)
     }
 
@@ -281,7 +281,7 @@ public extension Array where Element == Link {
         append(contentsOf: links)
     }
 
-    var json: [[String: Any]] {
+    var json: [JSONDictionary.Wrapped] {
         map(\.json)
     }
 

Sources/Shared/Publication/LinkRelation.swift

@@ -7,7 +7,7 @@
 import Foundation
 
 /// Link relations as defined in https://readium.org/webpub-manifest/relationships.html
-public struct LinkRelation {
+public struct LinkRelation: Sendable {
     /// The string representation of this link relation.
     public let string: String
 

Sources/Shared/Publication/LocalizedString.swift

@@ -10,7 +10,7 @@ import Foundation
 /// Can be either:
 ///   - a single nonlocalized string
 ///   - a dictionary of localized strings indexed by the BCP 47 language tag
-public enum LocalizedString: Hashable {
+public enum LocalizedString: Hashable, Sendable {
     case nonlocalized(String)
     case localized([String: String])
 

Sources/Shared/Publication/Locator.swift

@@ -8,7 +8,7 @@ import Foundation
 import ReadiumInternal
 
 /// https://github.com/readium/architecture/tree/master/locators
-public struct Locator: Hashable, CustomStringConvertible, Loggable {
+public struct Locator: Hashable, CustomStringConvertible, Loggable, Sendable {
     /// The URI of the resource that the Locator Object points to.
     public var href: String // URI
 
@@ -36,7 +36,7 @@ public struct Locator: Hashable, CustomStringConvertible, Loggable {
         if json == nil {
             return nil
         }
-        guard let jsonObject = json as? [String: Any],
+        guard let jsonObject = json as? JSONDictionary.Wrapped,
               let href = jsonObject["href"] as? String,
               let type = jsonObject["type"] as? String
         else {
@@ -82,7 +82,7 @@ public struct Locator: Hashable, CustomStringConvertible, Loggable {
     @available(*, unavailable, message: "This may create an incorrect `Locator` if the link `type` is missing. Use `publication.locate(Link)` instead.")
     public init(link: Link) { fatalError() }
 
-    public var json: [String: Any] {
+    public var json: JSONDictionary.Wrapped {
         makeJSON([
             "href": href,
             "type": type,
@@ -120,7 +120,7 @@ public struct Locator: Hashable, CustomStringConvertible, Loggable {
     ///
     /// Properties are mutable for convenience when making a copy, but the `locations` property
     /// is immutable in `Locator`, for safety.
-    public struct Locations: Hashable, Loggable, WarningLogger {
+    public struct Locations: Hashable, Loggable, WarningLogger, Sendable {
         /// Contains one or more fragment in the resource referenced by the `Locator`.
         public var fragments: [String]
         /// Progression in the resource expressed as a percentage (between 0 and 1).
@@ -131,15 +131,15 @@ public struct Locator: Hashable, CustomStringConvertible, Loggable {
         public var position: Int?
 
         /// Additional locations for extensions.
-        public var otherLocations: [String: Any] {
+        public var otherLocations: JSONDictionary.Wrapped {
             get { otherLocationsJSON.json }
             set { otherLocationsJSON = JSONDictionary(newValue) ?? JSONDictionary() }
         }
 
         // Trick to keep the struct equatable despite [String: Any]
         private var otherLocationsJSON: JSONDictionary
 
-        public init(fragments: [String] = [], progression: Double? = nil, totalProgression: Double? = nil, position: Int? = nil, otherLocations: [String: Any] = [:]) {
+        public init(fragments: [String] = [], progression: Double? = nil, totalProgression: Double? = nil, position: Int? = nil, otherLocations: JSONDictionary.Wrapped = [:]) {
             self.fragments = fragments
             self.progression = progression
             self.totalProgression = totalProgression
@@ -181,7 +181,7 @@ public struct Locator: Hashable, CustomStringConvertible, Loggable {
 
         public var isEmpty: Bool { json.isEmpty }
 
-        public var json: [String: Any] {
+        public var json: JSONDictionary.Wrapped {
             makeJSON([
                 "fragments": encodeIfNotEmpty(fragments),
                 "progression": encodeIfNotNil(progression),
@@ -197,7 +197,7 @@ public struct Locator: Hashable, CustomStringConvertible, Loggable {
         public subscript(key: String) -> Any? { otherLocations[key] }
     }
 
-    public struct Text: Hashable, Loggable {
+    public struct Text: Hashable, Loggable, Sendable {
         public var after: String?
         public var before: String?
         public var highlight: String?
@@ -213,7 +213,7 @@ public struct Locator: Hashable, CustomStringConvertible, Loggable {
                 self.init()
                 return
             }
-            guard let jsonObject = json as? [String: Any] else {
+            guard let jsonObject = json as? JSONDictionary.Wrapped else {
                 warnings?.log("Invalid Text object", model: Self.self, source: json)
                 throw JSONError.parsing(Self.self)
             }
@@ -234,7 +234,7 @@ public struct Locator: Hashable, CustomStringConvertible, Loggable {
             }
         }
 
-        public var json: [String: Any] {
+        public var json: JSONDictionary.Wrapped {
             makeJSON([
                 "after": encodeIfNotNil(after),
                 "before": encodeIfNotNil(before),
@@ -286,15 +286,15 @@ public extension Array where Element == Locator {
     /// Parses multiple JSON locators into an array of `Locator`.
     init(json: Any?, warnings: WarningLogger? = nil) {
         self.init()
-        guard let json = json as? [Any] else {
+        guard let json = json as? [JSONDictionary.Wrapped] else {
             return
         }
 
         let links = json.compactMap { try? Locator(json: $0, warnings: warnings) }
         append(contentsOf: links)
     }
 
-    var json: [[String: Any]] {
+    var json: [JSONDictionary.Wrapped] {
         map(\.json)
     }
 }
@@ -320,7 +320,7 @@ public struct _LocatorCollection: Hashable {
         if json == nil {
             return nil
         }
-        guard let jsonObject = json as? [String: Any] else {
+        guard let jsonObject = json as? JSONDictionary.Wrapped else {
             warnings?.log("Not a JSON object", model: Self.self, source: json)
             return nil
         }
@@ -331,7 +331,7 @@ public struct _LocatorCollection: Hashable {
         )
     }
 
-    public var json: [String: Any] {
+    public var json: JSONDictionary.Wrapped {
         makeJSON([
             "metadata": encodeIfNotEmpty(metadata.json),
             "links": encodeIfNotEmpty(links.json),
@@ -348,7 +348,7 @@ public struct _LocatorCollection: Hashable {
         public var numberOfItems: Int?
 
         /// Additional properties for extensions.
-        public var otherMetadata: [String: Any] {
+        public var otherMetadata: JSONDictionary.Wrapped {
             get { otherMetadataJSON.json }
             set { otherMetadataJSON = JSONDictionary(newValue) ?? JSONDictionary() }
         }
@@ -359,7 +359,7 @@ public struct _LocatorCollection: Hashable {
         public init(
             title: LocalizedStringConvertible? = nil,
             numberOfItems: Int? = nil,
-            otherMetadata: [String: Any] = [:]
+            otherMetadata: JSONDictionary.Wrapped = [:]
         ) {
             localizedTitle = title?.localizedString
             self.numberOfItems = numberOfItems
@@ -379,7 +379,7 @@ public struct _LocatorCollection: Hashable {
             }
         }
 
-        public var json: [String: Any] {
+        public var json: JSONDictionary.Wrapped {
             makeJSON([
                 "title": encodeIfNotNil(localizedTitle?.json),
                 "numberOfItems": encodeIfNotNil(numberOfItems),

Sources/Shared/Publication/Manifest.swift

@@ -11,7 +11,7 @@ import ReadiumInternal
 /// Manifest.
 ///
 /// See. https://readium.org/webpub-manifest/
-public struct Manifest: JSONEquatable, Hashable {
+public struct Manifest: JSONEquatable, Hashable, Sendable {
     public var context: [String] // @context
 
     public var metadata: Metadata
@@ -85,7 +85,7 @@ public struct Manifest: JSONEquatable, Hashable {
         subcollections = PublicationCollection.makeCollections(json: json.json, warnings: warnings)
     }
 
-    public var json: [String: Any] {
+    public var json: JSONDictionary.Wrapped {
         makeJSON([
             "@context": encodeIfNotEmpty(context),
             "metadata": metadata.json,