Merge pull request #14 from alickbass/geopoint-and-reference-encoding

Geopoint and reference encoding

Author: Oleksii Dykan

CodableFirebase/Decoder.swift

@@ -13,6 +13,7 @@ class _FirebaseDecoder : Decoder {
     struct _Options {
         let dateDecodingStrategy: FirebaseDecoder.DateDecodingStrategy?
         let dataDecodingStrategy: FirebaseDecoder.DataDecodingStrategy?
+        let skipGeoPointAndReference: Bool
         let userInfo: [CodingUserInfoKey : Any]
     }
 
@@ -1229,6 +1230,8 @@ extension _FirebaseDecoder {
         } else if T.self == Decimal.self || T.self == NSDecimalNumber.self {
             guard let decimal = try self.unbox(value, as: Decimal.self) else { return nil }
             decoded = decimal as! T
+        } else if options.skipGeoPointAndReference && (T.self is GeoPointType.Type || T.self is DocumentReferenceType.Type) {
+            decoded = value as! T
         } else {
             self.storage.push(container: value)
             decoded = try T(from: self)

CodableFirebase/Encoder.swift

@@ -13,6 +13,7 @@ class _FirebaseEncoder : Encoder {
     struct _Options {
         let dateEncodingStrategy: FirebaseEncoder.DateEncodingStrategy?
         let dataEncodingStrategy: FirebaseEncoder.DataEncodingStrategy?
+        let skipGeoPointAndReference: Bool
         let userInfo: [CodingUserInfoKey : Any]
     }
 
@@ -382,6 +383,11 @@ extension _FirebaseEncoder {
             return try self.box((value as! Data))
         } else if T.self == URL.self || T.self == NSURL.self {
             return self.box((value as! URL).absoluteString)
+        } else if options.skipGeoPointAndReference && (value is GeoPointType || value is DocumentReferenceType) {
+            guard let value = value as? NSObject else {
+                throw DocumentReferenceError.typeIsNotNSObject
+            }
+            return value
         }
 
         // The value should request a container from the _FirebaseEncoder.

CodableFirebase/FirebaseDecoder.swift

@@ -53,6 +53,7 @@ open class FirebaseDecoder {
         let options = _FirebaseDecoder._Options(
             dateDecodingStrategy: dateDecodingStrategy,
             dataDecodingStrategy: dataDecodingStrategy,
+            skipGeoPointAndReference: false,
             userInfo: userInfo
         )
         let decoder = _FirebaseDecoder(referencing: container, options: options)

CodableFirebase/FirebaseEncoder.swift

@@ -57,6 +57,7 @@ open class FirebaseEncoder {
         let options = _FirebaseEncoder._Options(
             dateEncodingStrategy: dateEncodingStrategy,
             dataEncodingStrategy: dataEncodingStrategy,
+            skipGeoPointAndReference: false,
             userInfo: userInfo
         )
         let encoder = _FirebaseEncoder(options: options)

CodableFirebase/FirestoreDecoder.swift

@@ -8,13 +8,26 @@
 
 import Foundation
 
+public protocol GeoPointType: Codable {
+    var latitude: Double { get }
+    var longitude: Double { get }
+    init(latitude: Double, longitude: Double)
+}
+
+public protocol DocumentReferenceType: Codable {}
+
 open class FirestoreDecoder {
     public init() {}
 
     open var userInfo: [CodingUserInfoKey : Any] = [:]
 
     open func decode<T : Decodable>(_ type: T.Type, from container: [String: Any]) throws -> T {
-        let options = _FirebaseDecoder._Options(dateDecodingStrategy: nil, dataDecodingStrategy: nil, userInfo: userInfo)
+        let options = _FirebaseDecoder._Options(
+            dateDecodingStrategy: nil,
+            dataDecodingStrategy: nil,
+            skipGeoPointAndReference: true,
+            userInfo: userInfo
+        )
         let decoder = _FirebaseDecoder(referencing: container, options: options)
         guard let value = try decoder.unbox(container, as: T.self) else {
             throw DecodingError.valueNotFound(T.self, DecodingError.Context(codingPath: [], debugDescription: "The given dictionary was invalid"))
@@ -23,3 +36,37 @@ open class FirestoreDecoder {
         return value
     }
 }
+
+enum GeoPointKeys: CodingKey {
+    case latitude, longitude
+}
+
+extension GeoPointType {
+    public init(from decoder: Decoder) throws {
+        let container = try decoder.container(keyedBy: GeoPointKeys.self)
+        let latitude = try container.decode(Double.self, forKey: .latitude)
+        let longitude = try container.decode(Double.self, forKey: .longitude)
+        self.init(latitude: latitude, longitude: longitude)
+    }
+    
+    public func encode(to encoder: Encoder) throws {
+        var container = encoder.container(keyedBy: GeoPointKeys.self)
+        try container.encode(latitude, forKey: .latitude)
+        try container.encode(longitude, forKey: .longitude)
+    }
+}
+
+enum DocumentReferenceError: Error {
+    case typeIsNotSupported
+    case typeIsNotNSObject
+}
+
+extension DocumentReferenceType {
+    public init(from decoder: Decoder) throws {
+        throw DocumentReferenceError.typeIsNotSupported
+    }
+    
+    public func encode(to encoder: Encoder) throws {
+        throw DocumentReferenceError.typeIsNotSupported
+    }
+}

CodableFirebase/FirestoreEncoder.swift

@@ -26,7 +26,12 @@ open class FirestoreEncoder {
     }
 
     internal func encodeToTopLevelContainer<Value : Encodable>(_ value: Value) throws -> Any {
-        let options = _FirebaseEncoder._Options(dateEncodingStrategy: nil, dataEncodingStrategy: nil, userInfo: userInfo)
+        let options = _FirebaseEncoder._Options(
+            dateEncodingStrategy: nil,
+            dataEncodingStrategy: nil,
+            skipGeoPointAndReference: true,
+            userInfo: userInfo
+        )
         let encoder = _FirebaseEncoder(options: options)
         guard let topLevel = try encoder.box_(value) else {
             throw EncodingError.invalidValue(value,

CodableFirebaseTests/TestCodableFirebase.swift

@@ -369,6 +369,19 @@ class TestCodableFirebase: XCTestCase {
         _testRoundTrip(of: 3 as Double)
     }
 
+    // MARK: - GeoPoint
+    func testEncodingGeoPoint() {
+        let point = Point(latitude: 2, longitude: 2)
+        XCTAssertEqual((try? FirebaseEncoder().encode(point)) as? NSDictionary, ["latitude": 2, "longitude": 2])
+        XCTAssertEqual(try? FirebaseDecoder().decode(Point.self, from: ["latitude": 2, "longitude": 2]), point)
+    }
+    
+    // MARK: - Document Reference
+    func testEncodingDocumentReference() {
+        XCTAssertThrowsError(try FirebaseEncoder().encode(DocumentReference()))
+        XCTAssertThrowsError(try FirebaseDecoder().decode(DocumentReference.self, from: []))
+    }
+    
     // MARK: - Helper Functions
     private var _emptyDictionary: [String: Any] = [:]
 
@@ -415,6 +428,19 @@ class TestCodableFirebase: XCTestCase {
 // MARK: - Test Types
 /* FIXME: Import from %S/Inputs/Coding/SharedTypes.swift somehow. */
 
+// MARK: - GeoPoint
+struct Point: GeoPointType, Equatable {
+    let latitude: Double
+    let longitude: Double
+    
+    static func == (lhs: Point, rhs: Point) -> Bool {
+        return lhs.latitude == rhs.latitude && lhs.longitude == rhs.longitude
+    }
+}
+
+// MARK: - ReferenceType
+fileprivate struct DocumentReference: DocumentReferenceType {}
+
 // MARK: - Empty Types
 fileprivate struct EmptyStruct : Codable, Equatable {
     static func ==(_ lhs: EmptyStruct, _ rhs: EmptyStruct) -> Bool {

CodableFirebaseTests/TestCodableFirestore.swift

@@ -109,6 +109,21 @@ class TestCodableFirestore: XCTestCase {
         _testRoundTrip(of: TopLevelWrapper(date), expected: ["value": date])
     }
 
+    // MARK: - GeoPoint & Document Reference
+    func testEncodingGeoPoint() {
+        let point = GeoPoint(latitude: 2, longitude: 2)
+        let wrapper = TopLevelWrapper(point)
+        XCTAssertEqual((try? FirestoreEncoder().encode(wrapper)) as NSDictionary?, ["value": point])
+        XCTAssertEqual(try? FirestoreDecoder().decode(TopLevelWrapper<GeoPoint>.self, from: ["value": point]), wrapper)
+        XCTAssertThrowsError(try FirestoreEncoder().encode(TopLevelWrapper(Point(latitude: 2, longitude: 2))))
+    }
+    
+    func testEncodingDocumentReference() {
+        let val = TopLevelWrapper(DocumentReference())
+        XCTAssertEqual((try? FirestoreEncoder().encode(val)) as NSDictionary?, ["value": val.value])
+        XCTAssertEqual(try? FirestoreDecoder().decode(TopLevelWrapper<DocumentReference>.self, from: ["value": val.value]), val)
+    }
+    
     private func _testEncodeFailure<T : Encodable>(of value: T) {
         do {
             let _ = try FirestoreEncoder().encode(value)
@@ -164,3 +179,21 @@ func expectEqualPaths(_ lhs: [CodingKey], _ rhs: [CodingKey], _ prefix: String)
         XCTAssertEqual(key1.stringValue, key2.stringValue, "\(prefix) CodingKey.stringValue mismatch: \(type(of: key1))('\(key1.stringValue)') != \(type(of: key2))('\(key2.stringValue)')")
     }
 }
+
+// MARK: - GeioPoint
+fileprivate class GeoPoint: NSObject, GeoPointType {
+    let latitude: Double
+    let longitude: Double
+    
+    required init(latitude: Double, longitude: Double) {
+        self.latitude = latitude
+        self.longitude = longitude
+    }
+    
+    static func == (lhs: Point, rhs: Point) -> Bool {
+        return lhs.latitude == rhs.latitude && lhs.longitude == rhs.longitude
+    }
+}
+
+// MARK: - ReferenceType
+fileprivate class DocumentReference: NSObject, DocumentReferenceType {}

README.md

@@ -86,6 +86,17 @@ Firestore.firestore().collection("data").document("one").getDocument { (document
 }
 ```
 
+### How to use `GeoPoint` and `DocumentRefence` in Firestore
+
+In order to use these 2 types with `Firestore`, you need to add the following code somewhere in your app:
+
+```swift
+extension DocumentReference: DocumentReferenceType {}
+extension GeoPoint: GeoPointType {}
+```
+
+and now they become `Codable` and can be used properly with `FirestoreEncoder` and `FirestoreDecoder`.
+
 ## Integration
 
 ### CocoaPods (iOS 9+)