Manage user updates

Update user details and receive real-time update events.

You can use PubNub's functionality via Blueprints or directly in C++ code.

• In Blueprints, the whole SDK is managed by a subsystem, so start by initalizing the PubnubChatSubsystem node. Afterwards, you can use the Pubnub Chat object reference.

Blueprint functions

The Blueprints provided in the documentation show how you can structure your application and may contain utility methods and elements like buttons that are not part of the Unreal Chat SDK and are meant to serve as guidance.

• In C++, you can use the PubNub SDK as any other Game Instance Subsystem.

  #include "Kismet/GameplayStatics.h"
  #include "PubnubChatSubsystem.h"
  
  
  UGameInstance* GameInstance = UGameplayStatics::GetGameInstance(this);
  UPubnubChatSubsystem* PubnubChatSubsystem = GameInstance->GetSubsystem<UPubnubChatSubsystem>();
  
  
  UPubnubChat* Chat = PubnubChatSubsystem ->InitChat("demo", "demo", "my_user") // config optional

  Chat now allows you to call all Chat SDK functions, for example:

  Chat->DeleteUser("SomeUserID");

Usage in Blueprints and C++

Requires App Context

Enable App Context in the Admin Portal to store user data.

Update user details

Edit user metadata with Update() or UpdateUser().

• Update() - call on a User object (no ID needed)
• UpdateUser() - call on a Chat object (requires user ID)

Method signature

Blueprint

C++ / Input parameters

• User->Update()

  1User->Update(FPubnubChatUserData UserData);

• Chat->UpdateUser()

  1Chat->UpdateUser(
  2    FString UserID, 
  3    FPubnubChatUserData UserData
  4);

Parameter	Required in User->Update()	Required in Chat->UpdateUser()	Description
UserID Type: FString Default: n/a	No	Yes	Unique user identifier.
UserData Type: FPubnubChatUserData Default: n/a	Yes	Yes	Additional user data.

FPubnubChatUserData

* required

Parameter	Description
UserName Type: FString Default: n/a	Display name for the user (must not be empty or consist only of whitespace characters).
ExternalID Type: FString Default: n/a	User's identifier in an external system. You can use it to match id with a similar identifier from an external database.
ProfileUrl Type: FString Default: n/a	URL of the user's profile picture.
Email Type: FString Default: n/a	User's email address.
CustomDataJson Type: FString Default: n/a	JSON providing custom data about the user. Values must be scalar only; arrays or objects are not supported. Filtering App Context data through the custom property is not recommended in SDKs.
Status Type: FString Default: n/a	Tag that lets you categorize your app users by their current state. The tag choice is entirely up to you and depends on your use case. For example, you can use status to mark users in your chat app as invited, active, or archived.
Type Type: FString Default: n/a	Tag that lets you categorize your app users by their functional roles. The tag choice is entirely up to you and depends on your use case. For example, you can use type to group users by their roles in your app, such as moderator, player, or support-agent.

API limits

To learn about the maximum length of parameters used to set user metadata, refer to REST API docs.

Output

Type	Description
UPubnubUser*	Returned object containing the updated user metadata.

Sample code

Change the link to the user's support_agent_15 LinkedIn profile to https://www.linkedin.com/mkelly_vp2.

• Update()

  1#include "Kismet/GameplayStatics.h"
  2#include "PubnubChatSubsystem.h"
  3
  
  4UGameInstance* GameInstance = UGameplayStatics::GetGameInstance(this);
  5UPubnubChatSubsystem* PubnubChatSubsystem = GameInstance->GetSubsystem<UPubnubChatSubsystem>();
  6
  
  7UPubnubChat* Chat = PubnubChatSubsystem ->InitChat("demo", "demo", "my_user");
  8
  
  9// Define user ID
  10FString UserID = "support_agent_15";
  11UPubnubUser* User = Chat->GetUser(UserID);
  12
  
  13FPubnubChatUserData UserData;
  14UserData.CustomDataJson = "{\"LinkedIn\":\"https://www.linkedin.com/mkelly_vp2\"}";
  15
  
  16// Update the user and save the reference
  17UPubnubUser* UpdatedUser = User->Update(UserData);

  show all 17 lines

• UpdateUser()

  1#include "Kismet/GameplayStatics.h"
  2#include "PubnubChatSubsystem.h"
  3
  
  4UGameInstance* GameInstance = UGameplayStatics::GetGameInstance(this);
  5UPubnubChatSubsystem* PubnubChatSubsystem = GameInstance->GetSubsystem<UPubnubChatSubsystem>();
  6
  
  7UPubnubChat* Chat = PubnubChatSubsystem ->InitChat("demo", "demo", "my_user");
  8
  
  9// Define user ID
  10FString UserID = "support_agent_15";
  11
  
  12FPubnubChatUserData UserData;
  13UserData.CustomDataJson = "{\"LinkedIn\":\"https://www.linkedin.com/mkelly_vp2\"}";
  14
  
  15// Update the user and save the reference
  16UPubnubUser* UpdatedUser = Chat->UpdateUser(UserID, UserData);

  show all 16 lines

Get user updates

Receive updates when User objects are edited or removed:

• StreamUpdates() - monitors a single user
• StreamUpdatesOn() - monitors multiple users

Both methods accept a callback invoked when user metadata changes. They subscribe to a channel and add an objects event listener, returning an unsubscribe function.

Callback behavior

• StreamUpdates() - returns updated User object (nullptr if deleted)
• StreamUpdatesOn() - returns complete list of monitored users on any change

Method signature

Blueprint

C++ / Input parameters

• StreamUpdates()

  1User->StreamUpdates(FOnPubnubUserStreamUpdateReceived UserUpdateCallback);

• StreamUpdatesOn()

  1User->StreamUpdatesOn(
  2    TArray<UPubnubUser*> Users, 
  3    FOnPubnubUserStreamUpdateReceived UserUpdateCallback
  4);

Parameter	Required in StreamUpdates()	Required in StreamUpdatesOn()	Description
Users Type: TArray<UPubnubUser*> Default: n/a	No	Yes	Array of User objects for which you want to get updates.
UserUpdateCallback Type: FOnPubnubUserStreamUpdateReceived Default: n/a	Yes	Yes	Callback function passed as a parameter to both methods. It defines the custom behavior to be executed when detecting channel metadata changes.

Each function in the Unreal Chat SDK that takes a callback as a parameter requires you to handle the response type accordingly.

For example, you can bind a callback function for the Channel->StreamPresence method to its handler in the following way:

1// Create a pubnub response delegate
2// you MUST implement your own callback function to handle the response
3FOnPubnubChannelStreamPresenceReceived PresenceResponse;
4PresenceResponse.BindDynamic(this, &AMyActor::OnPresenceResponseReceived);
5

6Channel->StreamPresence(PresenceResponse);

You can implement the callback function to handle the response as follows:

AMyActor.h

1UFUNCTION()
2void OnPresenceResponseReceived(const TArray<FString> &PresentUsersIDs);

AMyActor.cpp

1void AMyActor::OnPresenceResponseReceived(const TArray<FString> &PresentUsersIDs)
2{
3	for(auto PresentUser : PresentUsersIDs)
4	{
5		UE_LOG(LogTemp, Log, TEXT("Present User ID: "), *PresentUser);
6	}
7}

Handle the response

Output

Type	Description
UPubnubCallbackStop*	Object on which you can call Stop() to stop receiving updates.

Sample code

Get updates on support_agent_15.

• StreamUpdates()

  1#include "Kismet/GameplayStatics.h"
  2#include "PubnubChatSubsystem.h"
  3
  
  4UGameInstance* GameInstance = UGameplayStatics::GetGameInstance(this);
  5UPubnubChatSubsystem* PubnubChatSubsystem = GameInstance->GetSubsystem<UPubnubChatSubsystem>();
  6
  
  7UPubnubChat* Chat = PubnubChatSubsystem ->InitChat("demo", "demo", "my_user");
  8
  
  9// Define user ID
  10FString UserID = "support_agent_15";
  11
  
  12// Get the user and save the reference
  13UPubnubUser* User = Chat->GetUser(UserID);
  14
  
  15// Create a pubnub response delegate
  16// you MUST implement your own callback function to handle the response
  17FOnPubnubUserStreamUpdateReceived StreamUpdatesResponse;
  18StreamUpdatesResponse.BindDynamic(this, &AMyActor::OnPresenceResponseReceived);
  19
  
  20User->StreamUpdates(StreamUpdatesResponse);

  show all 20 lines

Get updates on support_agent_15 and support-manager.

• StreamUpdatesOn()

  1#include "Kismet/GameplayStatics.h"
  2#include "PubnubChatSubsystem.h"
  3
  
  4UGameInstance* GameInstance = UGameplayStatics::GetGameInstance(this);
  5UPubnubChatSubsystem* PubnubChatSubsystem = GameInstance->GetSubsystem<UPubnubChatSubsystem>();
  6
  
  7UPubnubChat* Chat = PubnubChatSubsystem ->InitChat("demo", "demo", "my_user");
  8
  
  9// Get the users and save the reference
  10UPubnubUser* User1 = Chat->GetUser("support_agent_15");
  11UPubnubUser* User2 = Chat->GetUser("support-manager");
  12
  
  13TArray<UPubnubUser*> Users;
  14Users.Add(User1);
  15Users.Add(User2);
  16
  
  17// Create a pubnub response delegate
  18// you MUST implement your own callback function to handle the response
  19FOnPubnubUserStreamUpdateReceived StreamUpdatesOnResponse;
  20StreamUpdatesOnResponse.BindDynamic(this, &AMyActor::OnPresenceResponseReceived);
  21
  
  22User->StreamUpdatesOn(Users, StreamUpdatesOnResponse);

  show all 22 lines

Other examples

Stop listening to updates on support_agent_15.

• StreamUpdates()

  1auto StopUpdates = User->StreamUpdates(StreamUpdatesResponse);
  2
  
  3StopUpdates->Stop();

Stop listening to updates on support_agent_15 and support-manager.

• StreamUpdatesOn()

  1auto StopUpdates = User->StreamUpdatesOn(Users, StreamUpdatesOnResponse);
  2
  
  3StopUpdates->Stop();