Handle parsing User when not all required properties are present

Author: wibosco

NetworkingInOperations-Example.xcodeproj/project.pbxproj

@@ -26,6 +26,7 @@
 		C284F0A620F63CBB009AF6E9 /* Assets.xcassets in Resources */ = {isa = PBXBuildFile; fileRef = C284F09C20F63CBB009AF6E9 /* Assets.xcassets */; };
 		C284F0A720F63CBB009AF6E9 /* LaunchScreen.storyboard in Resources */ = {isa = PBXBuildFile; fileRef = C284F09E20F63CBB009AF6E9 /* LaunchScreen.storyboard */; };
 		C284F0A820F63CBB009AF6E9 /* Main.storyboard in Resources */ = {isa = PBXBuildFile; fileRef = C284F0A020F63CBB009AF6E9 /* Main.storyboard */; };
+		C297683F2112F9DD006ED0B7 /* Decodable+Safe.swift in Sources */ = {isa = PBXBuildFile; fileRef = C297683E2112F9DD006ED0B7 /* Decodable+Safe.swift */; };
 		C29D5E2820F63BD60053D2AB /* NetworkingInOperations_ExampleTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = C29D5E2720F63BD60053D2AB /* NetworkingInOperations_ExampleTests.swift */; };
 /* End PBXBuildFile section */
 
@@ -60,6 +61,7 @@
 		C284F09C20F63CBB009AF6E9 /* Assets.xcassets */ = {isa = PBXFileReference; lastKnownFileType = folder.assetcatalog; path = Assets.xcassets; sourceTree = "<group>"; };
 		C284F09F20F63CBB009AF6E9 /* Base */ = {isa = PBXFileReference; lastKnownFileType = file.storyboard; name = Base; path = Base.lproj/LaunchScreen.storyboard; sourceTree = "<group>"; };
 		C284F0A120F63CBB009AF6E9 /* Base */ = {isa = PBXFileReference; lastKnownFileType = file.storyboard; name = Base; path = Base.lproj/Main.storyboard; sourceTree = "<group>"; };
+		C297683E2112F9DD006ED0B7 /* Decodable+Safe.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "Decodable+Safe.swift"; sourceTree = "<group>"; };
 		C29D5E0D20F63BD50053D2AB /* NetworkingInOperations-Example.app */ = {isa = PBXFileReference; explicitFileType = wrapper.application; includeInIndex = 0; path = "NetworkingInOperations-Example.app"; sourceTree = BUILT_PRODUCTS_DIR; };
 		C29D5E2320F63BD60053D2AB /* NetworkingInOperations-ExampleTests.xctest */ = {isa = PBXFileReference; explicitFileType = wrapper.cfbundle; includeInIndex = 0; path = "NetworkingInOperations-ExampleTests.xctest"; sourceTree = BUILT_PRODUCTS_DIR; };
 		C29D5E2720F63BD60053D2AB /* NetworkingInOperations_ExampleTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = NetworkingInOperations_ExampleTests.swift; sourceTree = "<group>"; };
@@ -128,6 +130,7 @@
 		3DFEAD2C210DE5B80076C30A /* Extensions */ = {
 			isa = PBXGroup;
 			children = (
+				C297683D2112F9C7006ED0B7 /* Decodable */,
 				3DFEAD2D210DE5B80076C30A /* NSObject */,
 			);
 			path = Extensions;
@@ -257,6 +260,14 @@
 			path = Storyboards;
 			sourceTree = "<group>";
 		};
+		C297683D2112F9C7006ED0B7 /* Decodable */ = {
+			isa = PBXGroup;
+			children = (
+				C297683E2112F9DD006ED0B7 /* Decodable+Safe.swift */,
+			);
+			path = Decodable;
+			sourceTree = "<group>";
+		};
 		C29D5E0420F63BD40053D2AB = {
 			isa = PBXGroup;
 			children = (
@@ -406,6 +417,7 @@
 				3DFEAD37210E1DA10076C30A /* AvatarRetrievalOperation.swift in Sources */,
 				C21F1CB320F902E100D4138F /* URLRequest+HTTPBody.swift in Sources */,
 				3DFEAD1F210DE0310076C30A /* QuestionsDataManager.swift in Sources */,
+				C297683F2112F9DD006ED0B7 /* Decodable+Safe.swift in Sources */,
 				3DFEAD26210DE14A0076C30A /* QuestionsURLRequestFactory.swift in Sources */,
 				3DFEAD21210DE0860076C30A /* Question.swift in Sources */,
 				C21F1CB520F902E100D4138F /* URLRequestFactory.swift in Sources */,

NetworkingInOperations-Example/Data/Managers/Questions/QuestionsDataManager.swift

@@ -25,5 +25,4 @@ class QuestionsDataManager {
         operation.completionHandler = completionHandler
         queueManager.enqueue(operation)
     }
-    
 }

NetworkingInOperations-Example/Data/Models/Question.swift

@@ -8,19 +8,34 @@
 
 import Foundation
 
+private struct DummyCodable: Codable {}
+
 struct QuestionPage: Codable {
+    
     let questions: [Question]
 
+    // MARK: - CodingKeys
+    
     enum CodingKeys: String, CodingKey {
         case questions = "items"
     }
+    
+    // MARK: - Init
+    
+    init(from decoder: Decoder) throws {        
+        let container = try decoder.container(keyedBy: CodingKeys.self)
+        questions = try container.decodeArrayByIgnoringInvalidElements(Question.self, forKey: .questions)
+    }
 }
 
 struct Question: Codable {
+    
     let questionID: Int
     let title: String
     let user: User
 
+    // MARK: - CodingKeys
+    
     enum CodingKeys: String, CodingKey {
         case questionID = "question_id"
         case title = "title"

NetworkingInOperations-Example/Data/Models/User.swift

@@ -14,6 +14,8 @@ struct User: Codable, Equatable {
     let name: String
     let avatarURL: String
 
+    // MARK: - CodingKeys
+    
     enum CodingKeys: String, CodingKey {
         case userID = "user_id"
         case name = "display_name"

NetworkingInOperations-Example/Data/Requests/QuestionsURLRequestFactory.swift

@@ -13,7 +13,7 @@ class QuestionsURLRequestFactory: URLRequestFactory {
     // MARK: - Retrieval
 
     func requestToRetrieveQuestions() -> URLRequest {
-        var request = jsonRequest(endPoint: "questions?order=desc&sort=activity&tagged=ios&site=stackoverflow")
+        var request = jsonRequest(endPoint: "questions?order=desc&sort=activity&tagged=ios&pagesize=100&site=stackoverflow")
         request.httpMethod = HTTPRequestMethod.get.rawValue
 
         return request

NetworkingInOperations-Example/Extensions/Decodable/Decodable+Safe.swift

@@ -0,0 +1,37 @@
+//
+//  Decodable+Safe.swift
+//  NetworkingInOperations-Example
+//
+//  Created by Boles, William (Developer) on 02/08/2018.
+//  Copyright © 2018 Boles. All rights reserved.
+//
+
+import Foundation
+
+fileprivate struct DummyCodable: Codable { }
+
+extension UnkeyedDecodingContainer {
+    
+    public mutating func decodeArrayByIgnoringInvalidElements<T>(_ type: T.Type) throws -> [T] where T : Decodable {
+        var decodedArray = [T]()
+        while !isAtEnd {
+            do {
+                let item = try decode(T.self)
+                decodedArray.append(item)
+            } catch let error {
+                print("ERROR decoding: \(error)")
+                _ = try? decode(DummyCodable.self) //Move container onto next item to be decoded
+            }
+        }
+        
+        return decodedArray
+    }
+}
+extension KeyedDecodingContainerProtocol {
+    
+    public func decodeArrayByIgnoringInvalidElements<T>(_ type: T.Type, forKey key: Self.Key) throws -> [T] where T : Decodable {
+        var unkeyedContainer = try nestedUnkeyedContainer(forKey: key)
+        
+        return try unkeyedContainer.decodeArrayByIgnoringInvalidElements(type)
+    }
+}