Merge pull request #17 from alickbass/field-type-support

Field type support

Author: Oleksii Dykan

CodableFirebase/Decoder.swift

@@ -13,7 +13,7 @@ class _FirebaseDecoder : Decoder {
     struct _Options {
         let dateDecodingStrategy: FirebaseDecoder.DateDecodingStrategy?
         let dataDecodingStrategy: FirebaseDecoder.DataDecodingStrategy?
-        let skipGeoPointAndReference: Bool
+        let skipFirestoreTypes: Bool
         let userInfo: [CodingUserInfoKey : Any]
     }
 
@@ -1230,7 +1230,7 @@ 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) {
+        } else if options.skipFirestoreTypes && (T.self is FirestoreDecodable.Type) {
             decoded = value as! T
         } else {
             self.storage.push(container: value)

CodableFirebase/Encoder.swift

@@ -13,7 +13,7 @@ class _FirebaseEncoder : Encoder {
     struct _Options {
         let dateEncodingStrategy: FirebaseEncoder.DateEncodingStrategy?
         let dataEncodingStrategy: FirebaseEncoder.DataEncodingStrategy?
-        let skipGeoPointAndReference: Bool
+        let skipFirestoreTypes: Bool
         let userInfo: [CodingUserInfoKey : Any]
     }
 
@@ -383,7 +383,7 @@ 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) {
+        } else if options.skipFirestoreTypes && (value is FirestoreEncodable) {
             guard let value = value as? NSObject else {
                 throw DocumentReferenceError.typeIsNotNSObject
             }

CodableFirebase/FirebaseDecoder.swift

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

CodableFirebase/FirebaseEncoder.swift

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

CodableFirebase/FirestoreDecoder.swift

@@ -8,14 +8,18 @@
 
 import Foundation
 
-public protocol GeoPointType: Codable {
+public protocol FirestoreDecodable: Decodable {}
+public protocol FirestoreEncodable: Encodable {}
+
+public typealias DocumentReferenceType = FirestoreDecodable & FirestoreEncodable
+public typealias FieldValueType = FirestoreEncodable
+
+public protocol GeoPointType: FirestoreDecodable, FirestoreEncodable {
     var latitude: Double { get }
     var longitude: Double { get }
     init(latitude: Double, longitude: Double)
 }
 
-public protocol DocumentReferenceType: Codable {}
-
 open class FirestoreDecoder {
     public init() {}
 
@@ -25,7 +29,7 @@ open class FirestoreDecoder {
         let options = _FirebaseDecoder._Options(
             dateDecodingStrategy: nil,
             dataDecodingStrategy: nil,
-            skipGeoPointAndReference: true,
+            skipFirestoreTypes: true,
             userInfo: userInfo
         )
         let decoder = _FirebaseDecoder(referencing: container, options: options)
@@ -61,11 +65,13 @@ enum DocumentReferenceError: Error {
     case typeIsNotNSObject
 }
 
-extension DocumentReferenceType {
+extension FirestoreDecodable {
     public init(from decoder: Decoder) throws {
         throw DocumentReferenceError.typeIsNotSupported
     }
-    
+}
+
+extension FirestoreEncodable {
     public func encode(to encoder: Encoder) throws {
         throw DocumentReferenceError.typeIsNotSupported
     }

CodableFirebase/FirestoreEncoder.swift

@@ -29,7 +29,7 @@ open class FirestoreEncoder {
         let options = _FirebaseEncoder._Options(
             dateEncodingStrategy: nil,
             dataEncodingStrategy: nil,
-            skipGeoPointAndReference: true,
+            skipFirestoreTypes: true,
             userInfo: userInfo
         )
         let encoder = _FirebaseEncoder(options: options)

README.md

@@ -86,17 +86,20 @@ Firestore.firestore().collection("data").document("one").getDocument { (document
 }
 ```
 
-### How to use `GeoPoint` and `DocumentRefence` in Firestore
+### How to use `GeoPoint`, `DocumentRefence`, `FieldValue` 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 {}
+extension FieldValue: FieldValueType {}
 ```
 
 and now they become `Codable` and can be used properly with `FirestoreEncoder` and `FirestoreDecoder`.
 
+***PLEASE NOTE*** that as `FieldValue` is only used to [`setData()` and `updateData()`](https://firebase.google.com/docs/reference/swift/firebasefirestore/api/reference/Classes/FieldValue), it only adopts the `Encodable` protocol. 
+
 ## Integration
 
 ### CocoaPods (iOS 9+)