Use Create User to hydrate OneSignal ID

* The initializer for the Request has optional PropertiesModel and optional SubscriptionModel
* This use case will send an external ID in the payload to retrieve the OneSignal ID.

Author: nan-li

iOS_SDK/OneSignalSDK/OneSignalUser/Source/Executors/OSUserExecutor.swift

@@ -190,6 +190,20 @@ extension OSUserExecutor {
         executePendingRequests()
     }
 
+    /**
+     This Create User call expects an Identity Model with external ID to hydrate the OneSignal ID
+     */
+    static func createUser(identityModel: OSIdentityModel) {
+        guard identityModel.externalId != nil else {
+            OneSignalLog.onesignalLog(.LL_ERROR, message: "createUser(identityModel) called with missing external ID")
+            return
+        }
+
+        let request = OSRequestCreateUser(identityModel: identityModel, propertiesModel: nil, pushSubscriptionModel: nil, originalPushToken: nil)
+        appendToQueue(request)
+        executePendingRequests()
+    }
+
     static func executeCreateUserRequest(_ request: OSRequestCreateUser) {
         guard !request.sentToClient else {
             return
@@ -200,8 +214,9 @@ extension OSUserExecutor {
         }
         request.sentToClient = true
 
-        // Hook up push subscription model, it may be updated with a subscription_id, etc.
-        if let pushSubscriptionModel = OneSignalUserManagerImpl.sharedInstance.pushSubscriptionModelStore.getModel(modelId: request.pushSubscriptionModel.modelId) {
+        // Hook up push subscription model if exists, it may be updated with a subscription_id, etc.
+        if let modelId = request.pushSubscriptionModel?.modelId,
+           let pushSubscriptionModel = OneSignalUserManagerImpl.sharedInstance.pushSubscriptionModelStore.getModel(modelId: modelId) {
             request.pushSubscriptionModel = pushSubscriptionModel
             request.updatePushSubscriptionModel(pushSubscriptionModel)
         }

iOS_SDK/OneSignalSDK/OneSignalUser/Source/Requests/OSRequestCreateUser.swift

@@ -30,7 +30,8 @@ import OneSignalCore
 /**
  This request will be made with the minimum information needed. The payload will contain an externalId or no identities.
  The push subscription may or may not have a token or suscriptionId already.
- There will be no properties sent.
+ This request is used for typical User Create, which will include properties and the push subscription,
+ or to hydrate OneSignal ID for a given External ID, which will only contain the Identity object in the payload.
  */
 class OSRequestCreateUser: OneSignalRequest, OSUserRequest {
     var sentToClient = false
@@ -40,7 +41,7 @@ class OSRequestCreateUser: OneSignalRequest, OSUserRequest {
     }
 
     var identityModel: OSIdentityModel
-    var pushSubscriptionModel: OSSubscriptionModel
+    var pushSubscriptionModel: OSSubscriptionModel?
     var originalPushToken: String?
 
     func prepareForExecution() -> Bool {
@@ -55,14 +56,17 @@ class OSRequestCreateUser: OneSignalRequest, OSUserRequest {
         return true
     }
 
-    // When reading from the cache, update the push subscription model
+    // When reading from the cache, update the push subscription model, if appropriate
     func updatePushSubscriptionModel(_ pushSubscriptionModel: OSSubscriptionModel) {
+        guard self.pushSubscriptionModel != nil else {
+            return
+        }
         self.pushSubscriptionModel = pushSubscriptionModel
         self.parameters?["subscriptions"] = [pushSubscriptionModel.jsonRepresentation()]
         self.originalPushToken = pushSubscriptionModel.address
     }
 
-    init(identityModel: OSIdentityModel, propertiesModel: OSPropertiesModel, pushSubscriptionModel: OSSubscriptionModel, originalPushToken: String?) {
+    init(identityModel: OSIdentityModel, propertiesModel: OSPropertiesModel?, pushSubscriptionModel: OSSubscriptionModel?, originalPushToken: String?) {
         self.identityModel = identityModel
         self.pushSubscriptionModel = pushSubscriptionModel
         self.originalPushToken = originalPushToken
@@ -78,14 +82,18 @@ class OSRequestCreateUser: OneSignalRequest, OSUserRequest {
         }
 
         // Properties Object
-        var propertiesObject: [String: Any] = [:]
-        propertiesObject["language"] = propertiesModel.language
-        propertiesObject["timezone_id"] = propertiesModel.timezoneId
-        params["properties"] = propertiesObject
+        if let propertiesModel = propertiesModel {
+            var propertiesObject: [String: Any] = [:]
+            propertiesObject["language"] = propertiesModel.language
+            propertiesObject["timezone_id"] = propertiesModel.timezoneId
+            params["properties"] = propertiesObject
+        }
 
         params["refresh_device_metadata"] = true
         self.parameters = params
-        self.updatePushSubscriptionModel(pushSubscriptionModel)
+        if let pushSub = pushSubscriptionModel {
+            self.updatePushSubscriptionModel(pushSub)
+        }
         self.method = POST
     }
 
@@ -102,7 +110,6 @@ class OSRequestCreateUser: OneSignalRequest, OSUserRequest {
     required init?(coder: NSCoder) {
         guard
             let identityModel = coder.decodeObject(forKey: "identityModel") as? OSIdentityModel,
-            let pushSubscriptionModel = coder.decodeObject(forKey: "pushSubscriptionModel") as? OSSubscriptionModel,
             let parameters = coder.decodeObject(forKey: "parameters") as? [String: Any],
             let rawMethod = coder.decodeObject(forKey: "method") as? UInt32,
             let path = coder.decodeObject(forKey: "path") as? String,
@@ -112,7 +119,7 @@ class OSRequestCreateUser: OneSignalRequest, OSUserRequest {
             return nil
         }
         self.identityModel = identityModel
-        self.pushSubscriptionModel = pushSubscriptionModel
+        self.pushSubscriptionModel = coder.decodeObject(forKey: "pushSubscriptionModel") as? OSSubscriptionModel
         self.originalPushToken = coder.decodeObject(forKey: "originalPushToken") as? String
         self.stringDescription = "<OSRequestCreateUser with externalId: \(identityModel.externalId ?? "nil")>"
         super.init()