Add OneSignalId and ExternalId getters as well as a user changed observer

MIGRATION_GUIDE.md

@@ -65,6 +65,14 @@ Once (or if) the user is no longer identifiable in your app (i.e. they logged ou
 
 Logging out has the affect of reverting to a “device-scoped” user, which is the new owner of the device’s push subscription.
 
+To observe changes to the onesignalId or externalId you can add a custom method to the event:
+
+    OneSignal.User.Changed += User_Changed;
+
+    private void User_Changed(object sender, OneSignalSDK.DotNet.Core.User.UserStateChangedEventArgs e) {
+        var user = e.State.Current;
+        ...
+    }
 
 ## Subscriptions
 
@@ -157,7 +165,10 @@ The user name space is accessible via `OneSignal.User` and provides access to us
 | **C#**                                                                        | **Description**                                                                                                                                                                                                                          |
 | ----------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
 | `IPushSubscription PushSubscription { get; }`                                 | *The push subscription associated to the current user.*                                                                                                                                                                                  |
-| `string Language { set; }`                                                    | *Set the 2-character language either as a detected language or explicitly set for this user.*                                                                                                                                            |
+| `string Language { set; }`                                                    | *Set the 2-character language either as a detected language or explicitly set for this user.*
+| `string OneSignalId`                                                          | *The UUID generated by OneSignal to represent a user, null if this is currently unavailable.*                                                                                                                                            |
+| `string ExternalId`                                                           | *The External ID is OneSignal's default and recommended alias label. This should be the mainidentifier you use to identify users. It is set when calling the [OneSignal.login] method. Return null if this is currently unavailable.* 
+| `event EventHandler<UserStateChangedEventArgs> Changed` | *Adds a change event that will run whenever the onesignalId or externalId has been changed.*
 | `void AddAlias(string label, string id)`                                      | *Set an alias for the current user.  If this alias already exists it will be overwritten.*                                                                                                                                               |
 | `void AddAliases(IDictionary<string, string> aliases)`                        | *Set aliases for the current user. If any alias already exists it will be overwritten.*                                                                                                                                                  |
 | `void RemoveAlias(string label)`                                              | *Remove an alias from the current user.*                                                                                                                                                                                                 |

OneSignalSDK.DotNet.Android.Core.Binding/Transforms/Metadata.xml

@@ -8,6 +8,7 @@
 	<attr path="/api/package[@name='com.onesignal.session']" name="managedName">Com.OneSignal.Android.Session</attr>
 	<attr path="/api/package[@name='com.onesignal.user']" name="managedName">Com.OneSignal.Android.User</attr>
 	<attr path="/api/package[@name='com.onesignal.user.subscriptions']" name="managedName">Com.OneSignal.Android.User.Subscriptions</attr>
+	<attr path="/api/package[@name='com.onesignal.user.state']" name="managedName">Com.OneSignal.Android.User.State</attr>
 
 	<remove-node path="/api/package[starts-with(@name, 'com.onesignal.common.events')]" />
 	<remove-node path="/api/package[starts-with(@name, 'com.onesignal.common.exceptions')]" />

OneSignalSDK.DotNet.Android/AndroidUserManager.cs

@@ -15,11 +15,33 @@ public string Language
 
         public IPushSubscription PushSubscription { get; } = new AndroidPushSubscription();
 
+        private InternalUserChangedHandler? _userChangedHandler;
+
         public void Initialize()
         {
+            _userChangedHandler = new InternalUserChangedHandler(this);
+            OneSignalNative.User.AddObserver(_userChangedHandler);
             ((AndroidPushSubscription)PushSubscription).Initialize();
         }
 
+        public string OneSignalId 
+        {
+            get {
+                string id = OneSignalNative.User.OnesignalId;
+                return string.IsNullOrEmpty(id)? null : id;
+            }
+        }
+
+        public string ExternalId 
+        {
+            get {
+                string id = OneSignalNative.User.ExternalId;
+                return string.IsNullOrEmpty(id)? null : id;
+            }
+        }
+
+        public event EventHandler<UserStateChangedEventArgs> Changed;
+
         public void AddAlias(string label, string id) => OneSignalNative.User.AddAlias(label, id);
         public void AddAliases(IDictionary<string, string> aliases) => OneSignalNative.User.AddAliases(aliases);
         public void RemoveAlias(string label) => OneSignalNative.User.RemoveAlias(label);
@@ -36,6 +58,35 @@ public void Initialize()
         public void RemoveTag(string key) => OneSignalNative.User.RemoveTag(key);
         public void RemoveTags(params string[] keys) => OneSignalNative.User.RemoveTags(keys);
         public IDictionary<string, string> GetTags() => OneSignalNative.User.Tags;
+
+        private sealed class InternalUserState : IUserState
+        {
+            public string OneSignalId { get; }
+
+            public string ExternalId { get; }
+
+            public InternalUserState(string onesignalId, string externalId)
+            {
+                OneSignalId = onesignalId;
+                ExternalId = externalId;
+            }
+        }
+
+        private class InternalUserChangedHandler : Java.Lang.Object, Com.OneSignal.Android.User.State.IUserStateObserver
+        {
+            private AndroidUserManager _manager;
+            public InternalUserChangedHandler(AndroidUserManager manager)
+            {
+                _manager = manager;
+            }
+
+            public void OnUserStateChange(Com.OneSignal.Android.User.State.UserChangedState state)
+            {
+                var current = new InternalUserState(state.Current.OnesignalId, state.Current.ExternalId);
+                var userChangedState = new UserChangedState(current);
+                _manager.Changed?.Invoke(_manager, new UserStateChangedEventArgs(userChangedState));
+            }
+        }
     }
 
     public class AndroidPushSubscription : IPushSubscription
@@ -99,5 +150,6 @@ public void OnPushSubscriptionChange(Com.OneSignal.Android.User.Subscriptions.Pu
                 _manager.Changed?.Invoke(_manager, new PushSubscriptionChangedEventArgs(changedState));
             }
         }
+
     }
 }

OneSignalSDK.DotNet.Core/User/IUserManager.cs

@@ -35,6 +35,24 @@ public interface IUserManager
         /// </summary>
         IPushSubscription PushSubscription { get; }
 
+        /// <summary>
+        /// The UUID generated by OneSignal to represent a user, null if this is currently unavailable.
+        /// </summary>
+        string OneSignalId { get; }
+
+        /// <summary>
+        /// The External ID is OneSignal's default and recommended alias label. This should be the main
+        /// identifier you use to identify users. It is set when calling the [OneSignal.login] method.
+        ///
+        /// This is null if the External ID has not been set.
+        /// </summary>
+        string ExternalId { get; }
+
+        /// <summary>
+        /// When onesignalId or externalId has changed
+        /// </summary>
+        event EventHandler<UserStateChangedEventArgs> Changed;
+
         /// <summary>
         /// Set an alias for the current user.  If this alias already exists it will be overwritten.
         /// </summary>

OneSignalSDK.DotNet.Core/User/IUserState.cs

@@ -0,0 +1,20 @@
+using System;
+
+namespace OneSignalSDK.DotNet.Core.User 
+{
+    public interface IUserState {
+        /// <summary>
+        /// The unique identifier for your OneSignal account. This will be an empty string until the
+        /// user has been successfully logged in on the backend and assigned an ID.
+        /// Use [Changed] to be notified when the [OneSignalId] has been successfully assigned.
+        /// </summary>
+        string OneSignalId { get; }
+
+        /// <summary>
+        /// The external identifier that you use to identify users. Use [Changed] to be notified
+        /// when the [ExternalId] has been successfully assigned. This will be an empty string if no
+        /// external identifier has been assigned to the associated [OneSignalId].
+        /// </summary>
+        string ExternalId { get; }
+    }
+}

OneSignalSDK.DotNet.Core/User/UserStateChangedEventArgs.cs

@@ -0,0 +1,24 @@
+using System;
+
+namespace OneSignalSDK.DotNet.Core.User
+{
+    /// <summary>
+    /// Several states associated with the SDK can be changed in and outside of the application.
+    /// </summary>
+    public class UserStateChangedEventArgs : EventArgs
+    {
+        public UserChangedState State { get; }
+
+        public UserStateChangedEventArgs(UserChangedState state) {
+            State = state;
+        }
+    }
+
+    public sealed class UserChangedState {
+        public IUserState Current { get; }
+
+        public UserChangedState(IUserState state) {
+            Current = state;
+        }
+    }
+}

OneSignalSDK.DotNet.iOS.Binding/ApiDefinitions.cs

@@ -444,6 +444,60 @@ interface OSPushSubscription
         void RemoveObserver(OSPushSubscriptionObserver observer);
     }
 
+    // @interface OSUserState : NSObject
+    [BaseType (typeof(NSObject), Name = "_TtC13OneSignalUser11OSUserState")]
+    [DisableDefaultCtor]
+    interface OSUserState
+    {
+        // @property (readonly, copy, nonatomic) NSString * _Nullable onesignalId;
+        [NullAllowed, Export ("onesignalId")]
+        string OnesignalId { get; }
+
+        // @property (readonly, copy, nonatomic) NSString * _Nullable externalId;
+        [NullAllowed, Export ("externalId")]
+        string ExternalId { get; }
+
+        // @property (readonly, copy, nonatomic) NSString * _Nonnull description;
+        [Export ("description")]
+        string Description { get; }
+
+        // -(NSDictionary * _Nonnull)jsonRepresentation __attribute__((warn_unused_result("")));
+        [Export ("jsonRepresentation")]
+        //[Verify (MethodToProperty)]
+        NSDictionary JsonRepresentation { get; }
+    }
+
+    // @interface OSUserChangedState : NSObject
+    [BaseType (typeof(NSObject), Name = "_TtC13OneSignalUser18OSUserChangedState")]
+    [DisableDefaultCtor]
+    interface OSUserChangedState
+    {
+        // @property (readonly, nonatomic, strong) OSUserState * _Nonnull current;
+        [Export ("current", ArgumentSemantic.Strong)]
+        OSUserState Current { get; }
+
+        // @property (readonly, copy, nonatomic) NSString * _Nonnull description;
+        [Export ("description")]
+        string Description { get; }
+
+        // -(NSDictionary * _Nonnull)jsonRepresentation __attribute__((warn_unused_result("")));
+        [Export ("jsonRepresentation")]
+        //[Verify (MethodToProperty)]
+        NSDictionary JsonRepresentation { get; }
+    }
+
+    // @protocol OSUserStateObserver
+    [Protocol (Name = "_TtP13OneSignalUser19OSUserStateObserver_")]
+    [Model]
+    [BaseType(typeof(NSObject))]
+    interface OSUserStateObserver
+    {
+        // @required -(void)onUserStateDidChangeWithState:(OSUserChangedState * _Nonnull)state;
+        //[Abstract]
+        [Export ("onUserStateDidChangeWithState:")]
+        void OnUserStateDidChangeWithState (OSUserChangedState state);
+    }
+
     // @protocol OSUser
     [Protocol(Name = "_TtP13OneSignalUser6OSUser_")]
     [BaseType(typeof(NSObject))]
@@ -454,6 +508,26 @@ interface OSUser
         [Export ("pushSubscription", ArgumentSemantic.Strong)]
         OSPushSubscription PushSubscription { get; }
 
+        // @required @property (readonly, copy, nonatomic) NSString * _Nullable onesignalId;
+        //[Abstract]
+        [NullAllowed, Export ("onesignalId")]
+        string OnesignalId { get; }
+
+        // @required @property (readonly, copy, nonatomic) NSString * _Nullable externalId;
+        //[Abstract]
+        [NullAllowed, Export ("externalId")]
+        string ExternalId { get; }
+
+        // @required -(void)addObserver:(id<OSUserStateObserver> _Nonnull)observer;
+        //[Abstract]
+        [Export ("addObserver:")]
+        void AddObserver (OSUserStateObserver observer);
+
+        // @required -(void)removeObserver:(id<OSUserStateObserver> _Nonnull)observer;
+        [Abstract]
+        [Export ("removeObserver:")]
+        void RemoveObserver (OSUserStateObserver observer);
+
         // @required -(void)addAliasWithLabel:(NSString * _Nonnull)label id:(NSString * _Nonnull)id;
         //[Abstract]
         [Export ("addAliasWithLabel:id:")]

OneSignalSDK.DotNet.iOS/iOSUserManager.cs

@@ -18,11 +18,26 @@ public string Language
 
         public IPushSubscription PushSubscription { get; } = new iOSPushSubscription();
 
+        private InternalUserChangedHandler _userChangedHandler;
+
         public void Initialize()
         {
+            _userChangedHandler = new InternalUserChangedHandler(this);
+            OneSignalNative.User.AddObserver(_userChangedHandler);
             ((iOSPushSubscription)PushSubscription).Initialize();
         }
 
+        public string OneSignalId 
+        {
+            get => OneSignalNative.User.OnesignalId;
+        }
+
+        public string ExternalId 
+        {
+            get => OneSignalNative.User.ExternalId;
+        }
+        public event EventHandler<UserStateChangedEventArgs>? Changed;
+
         public void AddAlias(string label, string id) => OneSignalNative.User.AddAliasWithLabel(label, id);
         public void AddAliases(IDictionary<string, string> aliases) => OneSignalNative.User.AddAliases(NativeConversion.DictToNSDict(aliases));
         public void RemoveAlias(string label) => OneSignalNative.User.RemoveAlias(label);
@@ -39,6 +54,35 @@ public void Initialize()
         public void RemoveTag(string key) => OneSignalNative.User.RemoveTag(key);
         public void RemoveTags(params string[] keys) => OneSignalNative.User.RemoveTags(keys);
         public IDictionary<string, string> GetTags() => FromNativeConversion.NSDictToPureStringDict(OneSignalNative.User.GetTags());
+
+        private sealed class InternalUserState : IUserState
+        {
+            public string OneSignalId { get; }
+
+            public string ExternalId { get; }
+
+            public InternalUserState(string onesignalId, string externalId)
+            {
+                OneSignalId = onesignalId;
+                ExternalId = externalId;
+            }
+        }
+
+        private class InternalUserChangedHandler : Com.OneSignal.iOS.OSUserStateObserver
+        {
+            private iOSUserManager _manager;
+            public InternalUserChangedHandler(iOSUserManager manager)
+            {
+                _manager = manager;
+            }
+
+            public override void OnUserStateDidChangeWithState(OSUserChangedState state)
+            {
+                var current = new InternalUserState(state.Current.OnesignalId, state.Current.ExternalId);
+                var userChangedState = new UserChangedState(current);
+                _manager.Changed?.Invoke(_manager, new UserStateChangedEventArgs(userChangedState));
+            }
+        }
     }
 
     public class iOSPushSubscription : IPushSubscription

Samples/OneSignalApp/Models/MainPageModel.cs

@@ -5,6 +5,7 @@
 using System.Windows.Input;
 using OneSignalSDK.DotNet;
 using OneSignalSDK.DotNet.Core.Debug;
+using OneSignalSDK.DotNet.Core.User;
 using OneSignalSDK.DotNet.Core.User.Subscriptions;
 
 namespace OneSignalApp.Models
@@ -190,6 +191,7 @@ public MainPageModel(Page page)
 
             OneSignal.Initialize(_appId);
 
+            OneSignal.User.Changed += User_Changed;
             OneSignal.User.PushSubscription.Changed += PushSubscription_Changed;
             OneSignal.Notifications.PermissionChanged += Notifications_PermissionChanged;
             OneSignal.Notifications.Clicked += Notifications_Clicked;
@@ -208,6 +210,12 @@ public MainPageModel(Page page)
             PushSubscriptionId = OneSignal.User.PushSubscription.Id;
         }
 
+        private void User_Changed(object sender, OneSignalSDK.DotNet.Core.User.UserStateChangedEventArgs e)
+        {
+            var user = e.State.Current;
+            Debug.WriteLine($"User has changed: OneSignalId=${user.OneSignalId}, ExternalId={user.ExternalId}");
+        }
+
         private void InAppMessages_Clicked(object sender, OneSignalSDK.DotNet.Core.InAppMessages.InAppMessageClickedEventArgs e)
         {
             Debug.WriteLine($"IAM clicked: ${e.Result.ActionId}.");