CodableCBOREncoder: save order for encoding Codable objects

Sources/CBORDecoder.swift

@@ -202,7 +202,7 @@ public class CBORDecoder {
     }
 }
 
-func getDateFromTimestamp(_ item: CBOR) throws -> Date {
+public func getDateFromTimestamp(_ item: CBOR) throws -> Date {
     switch item {
     case .double(let d):
         return Date(timeIntervalSince1970: TimeInterval(d))

Sources/Decoder/CodableCBORDecoder.swift

@@ -154,7 +154,7 @@ extension _CBORDecoder: Decoder {
     }
 }
 
-protocol CBORDecodingContainer: AnyObject {
+public protocol CBORDecodingContainer: AnyObject {
     var codingPath: [CodingKey] { get set }
 
     var userInfo: [CodingUserInfoKey : Any] { get }

Sources/Decoder/KeyedDecodingContainer.swift

@@ -49,7 +49,8 @@ extension _CBORDecoder {
             for _ in 0..<count {
                 guard let keyContainer = iterator.next() as? _CBORDecoder.SingleValueContainer,
                     let container = iterator.next() else {
-                        fatalError() // FIXME
+                    continue
+//                    fatalError() // FIXME
                 }
 
                 let keyVal: AnyCodingKey

Sources/Decoder/UnkeyedDecodingContainer.swift

@@ -48,22 +48,23 @@ extension _CBORDecoder {
 
         var currentIndex: Int = 0
 
-        lazy var nestedContainers: [CBORDecodingContainer] = {
+        lazy var nestedContainers: [CBORDecodingContainer?] = {
             guard let count = self.count else {
                 return []
             }
 
-            var nestedContainers: [CBORDecodingContainer] = []
+            var nestedContainers: [CBORDecodingContainer?] = []
 
-            do {
-                for _ in 0..<count {
+            for _ in 0..<count {
+                do {
                     let container = try self.decodeContainer()
                     nestedContainers.append(container)
+                } catch {
+                    print("<SwiftCBOR> ERROR: \(error)") // FIXME
+                    nestedContainers.append(nil)
                 }
-            } catch {
-                fatalError("\(error)") // FIXME
             }
-
+            
             self.currentIndex = 0
 
             return nestedContainers
@@ -125,7 +126,10 @@ extension _CBORDecoder.UnkeyedContainer: UnkeyedDecodingContainer {
         try checkCanDecodeValue()
         defer { self.currentIndex += 1 }
 
-        let container = self.nestedContainers[self.currentIndex]
+        guard let container = self.nestedContainers[self.currentIndex] else {
+            throw DecodingError.dataCorruptedError(in: self, debugDescription: "Failed to decode \(T.self)")
+        }
+
         let decoder = CodableCBORDecoder()
         decoder.setOptions(self.options)
         let value = try decoder.decode(T.self, from: container.data)
@@ -219,8 +223,12 @@ extension _CBORDecoder.UnkeyedContainer {
             }
             return container
         case 0xc0:
-            throw DecodingError.dataCorruptedError(in: self, debugDescription: "Handling text-based date/time is not supported yet")
-        // Tagged value (epoch-baed date/time)
+            // Tagged value (epoch-baed date/time)
+            print("<SwiftCBOR> ERROR: Handling text-based date/time is not supported yet")
+//            throw DecodingError.dataCorruptedError(in: self, debugDescription: "Handling text-based date/time is not supported yet")
+            // TODO: handle as c1 yet
+            length = try getLengthOfItem(format: try self.peekByte(), startIndex: startIndex.advanced(by: 1)) + 1
+
         case 0xc1:
             length = try getLengthOfItem(format: try self.peekByte(), startIndex: startIndex.advanced(by: 1)) + 1
         case 0xc2...0xdb:

Sources/Encoder/KeyedEncodingContainer.swift

@@ -2,7 +2,7 @@ import Foundation
 
 extension _CBOREncoder {
     final class KeyedContainer<Key: CodingKey> {
-        var storage: [AnyCodingKey: CBOREncodingContainer] = [:]
+        var storage: [(AnyCodingKey, CBOREncodingContainer)] = []
 
         var codingPath: [CodingKey]
         var userInfo: [CodingUserInfoKey: Any]
@@ -38,7 +38,9 @@ extension _CBOREncoder.KeyedContainer: KeyedEncodingContainerProtocol {
             userInfo: self.userInfo,
             options: self.options
         )
-        self.storage[anyCodingKeyForKey(key)] = container
+        let codingKey = anyCodingKeyForKey(key)
+        self.storage = self.storage.filter { $0.0 != codingKey }
+        self.storage.append( (codingKey, container) )
         return container
     }
 
@@ -48,7 +50,9 @@ extension _CBOREncoder.KeyedContainer: KeyedEncodingContainerProtocol {
             userInfo: self.userInfo,
             options: self.options
         )
-        self.storage[anyCodingKeyForKey(key)] = container
+        let codingKey = anyCodingKeyForKey(key)
+        self.storage = self.storage.filter { $0.0 != codingKey }
+        self.storage.append( (codingKey, container) )
         return container
     }
 
@@ -58,7 +62,9 @@ extension _CBOREncoder.KeyedContainer: KeyedEncodingContainerProtocol {
             userInfo: self.userInfo,
             options: self.options
         )
-        self.storage[anyCodingKeyForKey(key)] = container
+        let codingKey = anyCodingKeyForKey(key)
+        self.storage = self.storage.filter { $0.0 != codingKey }
+        self.storage.append( (codingKey, container) )
         return KeyedEncodingContainer(container)
     }
 

Tests/CBORDateTests.swift

@@ -0,0 +1,148 @@
+import XCTest
+import Foundation
+@testable import SwiftCBOR
+
+class CBORDateTests: XCTestCase {
+
+    struct CustomAndBool: Decodable {
+        let date: CustomDataDecodable
+        let bool: Bool
+
+        enum CodingKeys: Int, CodingKey {
+            case date = 0
+            case bool = 3
+        }
+    }
+
+    struct DateAndBool: Codable {
+        let date: Date
+        let bool: Bool
+
+        enum CodingKeys: Int, CodingKey {
+            case date = 0
+            case bool = 3
+        }
+    }
+
+    struct BoolOnly: Codable {
+        let bool: Bool
+
+        enum CodingKeys: Int, CodingKey {
+            case bool = 3
+        }
+    }
+
+    func testDecodeDate_C1_and_Date() {
+        let testData = Data(hex: "A2 00C11A682C4A77 03F5"
+            .replacingOccurrences(of: " ", with: ""))!
+        let decodedStruct = try! CodableCBORDecoder().decode(DateAndBool.self, from: testData)
+        XCTAssertNotNil(decodedStruct)
+    }
+
+    func testDecodeDate_C0_noFatalError() {
+        let testData = Data(hex: "A4 00C01A682C4A77 01C01A682C4A77 02C01A682C4A77 03F5"
+            .replacingOccurrences(of: " ", with: ""))!
+        do {
+            let _ = try CodableCBORDecoder().decode(DateAndBool.self, from: testData)
+            XCTFail("Must throw an error instead of fatalError")
+        } catch {
+            XCTAssertNotNil(error)
+        }
+    }
+
+    func testDecodeDate_C0_and_bool_noFatalErrorForPartialModel() {
+        let testData = Data(hex: "A4 00C01A682C4A77 01C01A682C4A77 02C01A682C4A77 03F5"
+            .replacingOccurrences(of: " ", with: ""))!
+        let decodedStruct = try? CodableCBORDecoder().decode(BoolOnly.self, from: testData)
+        XCTAssertNotNil(decodedStruct)
+    }
+
+    func testDecodeDate_C0_custom_epoch() {
+        //
+        let testData = Data(hex: "A4 00C01A682C4A7701C 01A682C4A77 02C01A682C4A77 03F5"
+            .replacingOccurrences(of: " ", with: ""))!
+        let decodedStruct = try? CodableCBORDecoder().decode(CustomAndBool.self, from: testData)
+        XCTAssertNotNil(decodedStruct?.date)
+        XCTAssertNotNil(decodedStruct)
+        XCTAssertNotNil(decodedStruct?.date.date)
+    }
+
+    func testDecodeDate_C0_custom_string() {
+        for formatter in [CustomDataDecodable.dateTimeWithMillisFormatter, CustomDataDecodable.dateTimeFormatter, CustomDataDecodable.onlyDateFormatter] {
+            let isoDate = formatter.string(from: Date())
+            let cbor = CBOR.tagged(CBOR.Tag.standardDateTimeString, .utf8String(isoDate))
+            let c0DateString = Data(cbor.encode()).hex
+
+            let testData = Data(hex: "A2 00 \(c0DateString) 03F5"
+                .replacingOccurrences(of: " ", with: ""))!
+
+            let decodedStruct = try? CodableCBORDecoder().decode(CustomAndBool.self, from: testData)
+            XCTAssertNotNil(decodedStruct?.date.date)
+
+            // just check that no any fatal error
+            let wrongDecodedStruct = try? CodableCBORDecoder().decode(DateAndBool.self, from: testData)
+            XCTAssertNil(wrongDecodedStruct)
+        }
+    }
+}
+
+/// it decodes C0 and C1 dates
+struct CustomDataDecodable: Decodable {
+    let date: Date
+    init(from decoder: Decoder) throws {
+        let container = (try decoder.singleValueContainer()) as? CBORDecodingContainer
+        guard let arrayData = container?.data else {
+            throw DecodingError.dataCorrupted(DecodingError.Context(codingPath: [], debugDescription: "can't cast to `CBORDecodingContainer`"))
+        }
+        self.date = try Self.dateFromCBORData(Data(arrayData))
+    }
+
+    static func dateFromCBORData(_ data: Data) throws -> Date {
+        let c0 = 0xC0 + CBOR.Tag.standardDateTimeString.rawValue
+        let c1 = 0xC0 + CBOR.Tag.epochBasedDateTime.rawValue
+        if data.count > 1, data[0] == c0 || data[0] == c1 { // 0xC0 or 0xC1
+            let timeData = data.suffix(from: 1)
+            let item = try CBOR.decode([UInt8](timeData))
+
+            if let item {
+                if let date = try? getDateFromTimestamp(item) {
+                    return date
+                } else if case .utf8String(let string) = item {
+                    for formatter in [Self.dateTimeWithMillisFormatter, Self.dateTimeFormatter, Self.onlyDateFormatter] {
+                        if let date = formatter.date(from: string) {
+                            return date
+                        }
+                    }
+                }
+            }
+        }
+        throw DecodingError.dataCorrupted(DecodingError.Context(codingPath: [], debugDescription: "CBOR Data to Date decode failed"))
+    }
+}
+
+extension CustomDataDecodable {
+
+    // 2017-01-23T10:12:31.484Z
+    static let dateTimeWithMillisFormatter: ISO8601DateFormatter = {
+        let v = ISO8601DateFormatter()
+        v.timeZone = TimeZone(identifier: "UTC")
+        v.formatOptions = [.withInternetDateTime, .withFractionalSeconds]
+        return v
+    }()
+
+    // 2021-06-30T19:22:31Z
+    static let dateTimeFormatter: ISO8601DateFormatter = {
+        let v = ISO8601DateFormatter()
+        v.timeZone = TimeZone(identifier: "UTC")
+        v.formatOptions = [.withInternetDateTime]
+        return v
+    }()
+
+    // 2016-06-13
+    static let onlyDateFormatter: ISO8601DateFormatter = {
+        let v = ISO8601DateFormatter()
+        v.timeZone = TimeZone(identifier: "UTC")
+        v.formatOptions = .withFullDate
+        return v
+    }()
+}

Tests/CodableCBOREncoderTests.swift

@@ -127,7 +127,6 @@ class CodableCBOREncoderTests: XCTestCase {
 
         XCTAssert(
             encoded == [0xa2, 0x63, 0x61, 0x67, 0x65, 0x18, 0x1b, 0x64, 0x6e, 0x61, 0x6d, 0x65, 0x63, 0x48, 0x61, 0x6d]
-            || encoded == [0xa2, 0x64, 0x6e, 0x61, 0x6d, 0x65, 0x63, 0x48, 0x61, 0x6d, 0x63, 0x61, 0x67, 0x65, 0x18, 0x1b]
         )
     }
 }