Expose Entity properties on EntityType protocol.

JSONAPI.playground/Pages/Usage.xcplaygroundpage/Contents.swift

@@ -47,3 +47,13 @@ if case let .data(bodyData) = peopleResponse.body {
 } else {
 	print("no body data")
 }
+
+// MARK: - Work in the abstract
+
+func process<T: JSONAPIDocument>(document: T) {
+	guard case let .data(body) = document.body else {
+		return
+	}
+	let x: T.BodyData = body
+}
+process(document: peopleResponse)

Sources/JSONAPI/Document/Document.swift

@@ -6,11 +6,16 @@
 //
 
 public protocol JSONAPIDocument: Codable, Equatable {
-	associatedtype ResourceBody: JSONAPI.ResourceBody
+	associatedtype PrimaryResourceBody: JSONAPI.ResourceBody
 	associatedtype MetaType: JSONAPI.Meta
 	associatedtype LinksType: JSONAPI.Links
 	associatedtype IncludeType: JSONAPI.Include
 	associatedtype Error: JSONAPIError
+
+	typealias Body = Document<PrimaryResourceBody, MetaType, LinksType, IncludeType, Error>.Body
+	typealias BodyData = Body.Data
+
+	var body: Body { get }
 }
 
 /// A JSON API Document represents the entire body
@@ -20,7 +25,7 @@ public protocol JSONAPIDocument: Codable, Equatable {
 /// API uses snake case, you will want to use
 /// a conversion such as the one offerred by the
 /// Foundation JSONEncoder/Decoder: `KeyDecodingStrategy`
-public struct Document<ResourceBody: JSONAPI.ResourceBody, MetaType: JSONAPI.Meta, LinksType: JSONAPI.Links, IncludeType: JSONAPI.Include, Error: JSONAPIError>: JSONAPIDocument {
+public struct Document<PrimaryResourceBody: JSONAPI.ResourceBody, MetaType: JSONAPI.Meta, LinksType: JSONAPI.Links, IncludeType: JSONAPI.Include, Error: JSONAPIError>: JSONAPIDocument {
 	public typealias Include = IncludeType
 
 	public let body: Body
@@ -31,10 +36,10 @@ public struct Document<ResourceBody: JSONAPI.ResourceBody, MetaType: JSONAPI.Met
 		case data(Data)
 
 		public struct Data: Equatable {
-			let primary: ResourceBody
-			let includes: Includes<Include>
-			let meta: MetaType
-			let links: LinksType
+			public let primary: PrimaryResourceBody
+			public let includes: Includes<Include>
+			public let meta: MetaType
+			public let links: LinksType
 		}
 
 		public var isError: Bool {
@@ -47,7 +52,7 @@ public struct Document<ResourceBody: JSONAPI.ResourceBody, MetaType: JSONAPI.Met
 			return errors
 		}
 		
-		public var primaryData: ResourceBody? {
+		public var primaryData: PrimaryResourceBody? {
 			guard case let .data(data) = self else { return nil }
 			return data.primary
 		}
@@ -84,49 +89,49 @@ public struct Document<ResourceBody: JSONAPI.ResourceBody, MetaType: JSONAPI.Met
 		body = .errors(errors, meta: meta, links: links)
 	}
 
-	public init(body: ResourceBody, includes: Includes<Include>, meta: MetaType, links: LinksType) {
+	public init(body: PrimaryResourceBody, includes: Includes<Include>, meta: MetaType, links: LinksType) {
 		self.body = .data(.init(primary: body, includes: includes, meta: meta, links: links))
 	}
 }
 
 extension Document where IncludeType == NoIncludes {
-	public init(body: ResourceBody, meta: MetaType, links: LinksType) {
+	public init(body: PrimaryResourceBody, meta: MetaType, links: LinksType) {
 		self.body = .data(.init(primary: body, includes: .none, meta: meta, links: links))
 	}
 }
 
 extension Document where MetaType == NoMetadata {
-	public init(body: ResourceBody, includes: Includes<Include>, links: LinksType) {
+	public init(body: PrimaryResourceBody, includes: Includes<Include>, links: LinksType) {
 		self.body = .data(.init(primary: body, includes: includes, meta: .none, links: links))
 	}
 }
 
 extension Document where LinksType == NoLinks {
-	public init(body: ResourceBody, includes: Includes<Include>, meta: MetaType) {
+	public init(body: PrimaryResourceBody, includes: Includes<Include>, meta: MetaType) {
 		self.body = .data(.init(primary: body, includes: includes, meta: meta, links: .none))
 	}
 }
 
 extension Document where IncludeType == NoIncludes, LinksType == NoLinks {
-	public init(body: ResourceBody, meta: MetaType) {
+	public init(body: PrimaryResourceBody, meta: MetaType) {
 		self.body = .data(.init(primary: body, includes: .none, meta: meta, links: .none))
 	}
 }
 
 extension Document where IncludeType == NoIncludes, MetaType == NoMetadata {
-	public init(body: ResourceBody, links: LinksType) {
+	public init(body: PrimaryResourceBody, links: LinksType) {
 		self.body = .data(.init(primary: body, includes: .none, meta: .none, links: links))
 	}
 }
 
 extension Document where MetaType == NoMetadata, LinksType == NoLinks {
-	public init(body: ResourceBody, includes: Includes<Include>) {
+	public init(body: PrimaryResourceBody, includes: Includes<Include>) {
 		self.body = .data(.init(primary: body, includes: includes, meta: .none, links: .none))
 	}
 }
 
 extension Document where IncludeType == NoIncludes, MetaType == NoMetadata, LinksType == NoLinks {
-	public init(body: ResourceBody) {
+	public init(body: PrimaryResourceBody) {
 		self.body = .data(.init(primary: body, includes: .none, meta: .none, links: .none))
 	}
 }
@@ -174,11 +179,11 @@ extension Document {
 			return
 		}
 
-		let data: ResourceBody
-		if let noData = NoResourceBody() as? ResourceBody {
+		let data: PrimaryResourceBody
+		if let noData = NoResourceBody() as? PrimaryResourceBody {
 			data = noData
 		} else {
-			data = try container.decode(ResourceBody.self, forKey: .data)
+			data = try container.decode(PrimaryResourceBody.self, forKey: .data)
 		}
 
 		let maybeIncludes = try container.decodeIfPresent(Includes<Include>.self, forKey: .included)

Sources/JSONAPI/Document/ResourceBody.swift

@@ -1,5 +1,5 @@
 //
-//  ResourceBody.swift
+//  PrimaryResourceBody.swift
 //  JSONAPI
 //
 //  Created by Mathew Polzin on 11/10/18.
@@ -80,12 +80,12 @@ extension ManyResourceBody {
 
 extension SingleResourceBody: CustomStringConvertible {
 	public var description: String {
-		return "ResourceBody(\(String(describing: value)))"
+		return "PrimaryResourceBody(\(String(describing: value)))"
 	}
 }
 
 extension ManyResourceBody: CustomStringConvertible {
 	public var description: String {
-		return "ResourceBody(\(String(describing: values)))"
+		return "PrimaryResourceBody(\(String(describing: values)))"
 	}
 }

Sources/JSONAPI/Resource/Entity.swift

@@ -43,6 +43,18 @@ public protocol EntityType: PrimaryResource {
 
 	typealias Attributes = Description.Attributes
 	typealias Relationships = Description.Relationships
+
+	/// The `Entity`'s Id. This can be of type `Unidentified` if
+	/// the entity is being created clientside and the
+	/// server is being asked to create a unique Id. Otherwise,
+	/// this should be of a type conforming to `IdType`.
+	var id: Identifier { get }
+
+	/// The JSON API compliant attributes of this `Entity`.
+	var attributes: Attributes { get }
+
+	/// The JSON API compliant relationships of this `Entity`.
+	var relationships: Relationships { get }
 }
 
 /// An `Entity` is a single model type that can be

Sources/JSONAPI/Resource/Id.swift

@@ -8,7 +8,7 @@
 /// Any type that you would like to be encoded to and
 /// decoded from JSON API ids should conform to this
 /// protocol. Conformance for `String` is given.
-public protocol RawIdType: Codable, Equatable {}
+public protocol RawIdType: Codable, Hashable {}
 
 /// If you would like to be able to create new
 /// Entities with Ids backed by a RawIdType then
@@ -32,7 +32,7 @@ public struct Unidentified<EntityDescription: JSONAPI.EntityDescription>: Identi
 	public var description: String { return "Id(Unidentified)" }
 }
 
-public protocol IdType: Identifier, CustomStringConvertible {
+public protocol IdType: Identifier, Hashable, CustomStringConvertible {
 	associatedtype RawType: RawIdType
 	
 	var rawValue: RawType { get }