Add ModelStorage Codable extensions

Author: colemancda

Sources/CoreModel/Decodable.swift

@@ -7,6 +7,8 @@
 
 import Foundation
 
+// MARK: - ModelData Decoding
+
 public extension ModelData {
 
     func decode<T, K>(_ type: T.Type, forKey key: K) throws -> T where T: AttributeDecodable, K: CodingKey {
@@ -67,11 +69,15 @@ public extension ModelData {
     }
 }
 
+// MARK: - Default Codable Implementation
+
 extension Entity where Self: Decodable, Self.ID: Decodable {
 
     // TODO: Default implementation for Decodable
 }
 
+// MARK: - AttributeDecodable
+
 public protocol AttributeDecodable {
 
     init?(attributeValue: AttributeValue)

Sources/CoreModel/Encodable.swift

@@ -7,6 +7,8 @@
 
 import Foundation
 
+// MARK: - ModelData Encoding
+
 public extension ModelData {
 
     mutating func encode<T, K>(_ value: T, forKey key: K) where T: AttributeEncodable, K: CodingKey {
@@ -30,19 +32,14 @@ public extension ModelData {
     }
 }
 
+// MARK: - Default Codable Implementation
+
 extension Entity where Self: Encodable, Self.ID: Encodable {
 
     // TODO: Default implementation for Encodable
 }
 
-public extension ModelStorage {
-    
-    /// Create or edit a managed object.
-    func insert<T>(_ value: T) async throws where T: Entity, T: Encodable {
-        let model = value.encode()
-        try await insert(model)
-    }
-}
+// MARK: - AttributeEncodable
 
 public protocol AttributeEncodable {
 

Sources/CoreModel/Store.swift

@@ -6,6 +6,8 @@
 //  Copyright © 2015 PureSwift. All rights reserved.
 //
 
+import Predicate
+
 /// CoreModel Store Protocol
 public protocol ModelStorage: AnyObject {
 
@@ -32,6 +34,8 @@ public extension ModelStorage {
     }
 }
 
+// MARK: - ModelData
+
 /// CoreModel Object Instance
 public struct ModelData: Equatable, Hashable, Identifiable, Codable {
 
@@ -55,3 +59,63 @@ public struct ModelData: Equatable, Hashable, Identifiable, Codable {
         self.relationships = relationships
     }
 }
+
+// MARK: - ModelStorage Codable Extensions
+
+public extension ModelStorage {
+    
+    /// Fetch managed object.
+    func fetch<T>(_ entity: T.Type, for id: ObjectID) async throws -> T? where T: Entity {
+        guard let model = try await fetch(T.entityName, for: id) else {
+            return nil
+        }
+        return try T.init(from: model)
+    }
+    
+    /// Fetch managed objects.
+    func fetch<T>(
+        _ entity: T.Type,
+        sortDescriptors: [FetchRequest.SortDescriptor] = [],
+        predicate: Predicate? = nil,
+        fetchLimit: Int = 0,
+        fetchOffset: Int = 0
+    ) async throws -> [ModelData] where T: Entity {
+        let fetchRequest = FetchRequest(
+            entity: T.entityName,
+            sortDescriptors: sortDescriptors,
+            predicate: predicate,
+            fetchLimit: fetchLimit,
+            fetchOffset: fetchOffset
+        )
+        return try await fetch(fetchRequest)
+    }
+    
+    /// Fetch and return result count.
+    func count<T>(
+        _ entity: T.Type,
+        sortDescriptors: [FetchRequest.SortDescriptor] = [],
+        predicate: Predicate? = nil,
+        fetchLimit: Int = 0,
+        fetchOffset: Int = 0
+    ) async throws -> UInt where T: Entity {
+        let fetchRequest = FetchRequest(
+            entity: T.entityName,
+            sortDescriptors: sortDescriptors,
+            predicate: predicate,
+            fetchLimit: fetchLimit,
+            fetchOffset: fetchOffset
+        )
+        return try await count(fetchRequest)
+    }
+    
+    /// Create or edit a managed object.
+    func insert<T>(_ value: T) async throws where T: Entity, T: Encodable {
+        let model = value.encode()
+        try await insert(model)
+    }
+    
+    /// Delete the specified managed object.
+    func delete<T>(_ entity: T.Type, for id: ObjectID) async throws where T: Entity {
+        try await delete(T.entityName, for: id)
+    }
+}