Manage the user-channel membership relation

When a user joins a channel or gets invited to it, a membership relation between that user and the channel is created (Membership entity). The membership ends when this user leaves the channel.

Usage in Blueprints and C++

Requires App Context

To set up and manage channel membership, you must enable App Context for your app's keyset in the Admin Portal.

Read on to learn how to check and update user-channel membership.

Get members

GetMembers() returns the list of all channel members.

Method signature

Blueprint

C++ / Input parameters

Channel->GetMembers(
    FString Filter = "", 
    FString Sort = "", 
    int Limit = 0, 
    FPubnubPage Page = FPubnubPage()
);

Parameter	Type	Required	Default	Description
Filter	FString	No	n/a	Expression used to filter the results. Returns only these channels whose properties satisfy the given expression are returned. The filter language is defined here.
Sort	FString	No	n/a	Key-value pair of a property to sort by, and a sort direction. Available options are id, name, and updated. Use asc or desc to specify the sorting direction, or specify null to take the default sorting direction (ascending). For example: {name: "asc"}. By default, the items are sorted by the last updated date.
Limit	int	No	100	Number of objects to return in response. The default (and maximum) value is 100.
Page	FPubnubPage	No	n/a	Object used for pagination to define which previous or next result page you want to fetch.
→ Next	FString	No	n/a	Random string returned from the server, indicating a specific position in a data set. Used for forward pagination, it fetches the next page, allowing you to continue from where you left off.
→ Prev	FString	No	n/a	Random string returned from the server, indicating a specific position in a data set. Used for backward pagination, it fetches the previous page, enabling access to earlier data. Ignored if the Next parameter is supplied.

Output

Parameter	Type	Description
FPubnubMembersResponseWrapper	struct	Returned object containing these fields: Page, Total, Status, and Memberships.
→ Page	FPubnubPage	Object used for pagination to define which previous or next result page you want to fetch.
→ Next	FString	Random string returned from the server, indicating a specific position in a data set. Used for forward pagination, it fetches the next page, allowing you to continue from where you left off.
→ Prev	FString	Random string returned from the server, indicating a specific position in a data set. Used for backward pagination, it fetches the previous page, enabling access to earlier data. Ignored if the Next parameter is supplied.
→ Total	int	Total number of channel members.
→ Status	FString	Status code of a server response, like 200.
→ Memberships	TArray<UPubnubMembership*>	Array of all related memberships.

Basic usage

List all members of the support channel on the premium support plan.

#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");

UPubnubChannel* Channel = Chat->GetChannel("support");

// Define the filter for members with "premium" support plan
FString Filter = "custom.support_plan == 'premium'";

// Fetch the members with the filter
FPubnubMembersResponseWrapper Members = Channel->GetMembers(Filter);

Get membership

GetMemberships() returns the list of all channel memberships of a given user.

To get a list of all existing channels, use the GetChannels() method.

Blueprint

C++ / Input parameters

User->GetMemberships(
    FString Filter = "", 
    FString Sort = "", 
    int Limit = 0, 
    FPubnubPage Page = FPubnubPage()
);

Parameter	Type	Required	Default	Description
Filter	FString	No	n/a	Expression used to filter the results. Returns only these channels whose properties satisfy the given expression are returned. The filter language is defined here.
Sort	FString	No	n/a	Key-value pair of a property to sort by, and a sort direction. Available options are id, name, and updated. Use asc or desc to specify the sorting direction, or specify null to take the default sorting direction (ascending). For example: {name: "asc"}. By default, the items are sorted by the last updated date.
Limit	int	No	100	Number of objects to return in response. The default (and maximum) value is 100.
Page	FPubnubPage	No	n/a	Object used for pagination to define which previous or next result page you want to fetch.
→ Next	FString	No	n/a	Random string returned from the server, indicating a specific position in a data set. Used for forward pagination, it fetches the next page, allowing you to continue from where you left off.
→ Prev	FString	No	n/a	Random string returned from the server, indicating a specific position in a data set. Used for backward pagination, it fetches the previous page, enabling access to earlier data. Ignored if the Next parameter is supplied.

Output

Parameter	Type	Description
FPubnubMembershipsResponseWrapper	struct	Returned object containing these fields: Page, Total, Status, and Memberships.
→ Page	FPubnubPage	Object used for pagination to define which previous or next result page you want to fetch.
→ Next	FString	Random string returned from the server, indicating a specific position in a data set. Used for forward pagination, it fetches the next page, allowing you to continue from where you left off.
→ Prev	FString	Random string returned from the server, indicating a specific position in a data set. Used for backward pagination, it fetches the previous page, enabling access to earlier data. Ignored if the Next parameter is supplied.
→ Total	int	Total number of channel members.
→ Status	FString	Status code of a server response, like 200.
→ Memberships	TArray<UPubnubMembership*>	Array of all related memberships.

Basic usage

Find out which channels the support_agent_15 user is a member of.

#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");

// Define user ID
FString UserID = "support_agent_15";

// Get the user and save the reference
UPubnubUser* User = Chat->GetUser(UserID);

FPubnubMembershipsResponseWrapper Memberships = User->GetMemberships();

Get updates

You can receive updates when specific user-channel Membership object(s) are added, edited, or removed using the following methods:

• StreamUpdates() checks updates on a single Membership object.
• StreamUpdatesOn() checks updates on a list of Membership objects.

Both methods accept a callback function as an argument. The Unreal Chat SDK invokes this callback whenever someone adds, changes, or removes membership data.

Underneath, these methods subscribe the current user to a channel and add an objects event listener to receive all objects events of type membership. These methods also return the unsubscribe function you can invoke to stop receiving objects events and unsubscribe from the channel.

Method signature

Blueprint

C++ / Input parameters

• StreamUpdates()

  Membership->StreamUpdates(FOnPubnubMembershipStreamUpdateReceived MembershipUpdateCallback);

• StreamUpdatesOn()

  Membership->StreamUpdatesOn(
      TArray<UPubnubMembership*> Memberships, 
      FOnPubnubMembershipStreamUpdateReceived MembershipUpdateCallback
  );

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

Handle the response

Output

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

Basic usage

Get updates on the first user membership.

• StreamUpdates()

  #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");
  
  // Get the users and save the reference
  UPubnubUser* User1 = Chat->GetUser("support_agent_15");
  
  FPubnubMembershipsResponseWrapper Memberships = User->GetMemberships();
  
  UPubnubMembership* Membership = Memberships.Memberships[0];
  

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Get updates on the first page of user memberships.

• StreamUpdatesOn()

  #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");
  
  // Get the users and save the reference
  UPubnubUser* User1 = Chat->GetUser("support_agent_15");
  TArray<UPubnubMembership*> Memberships = User->GetMemberships().Memberships;
  
  // Create a pubnub response delegate
  // you MUST implement your own callback function to handle the response
  FOnPubnubMembershipStreamUpdateReceived MembershipUpdatesOnResponse;

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Other examples

Stop listening to updates on the first user membership.

• StreamUpdates()

  auto StopUpdates = Membership->StreamUpdates(MembershipUpdatesResponse);
  
  StopUpdates->Stop();

Stop listening to updates on the first page of user memberships.

• StreamUpdatesOn()

  auto StopUpdates = Membership->StreamUpdatesOn(MembershipUpdatesOnResponse);
  
  StopUpdates->Stop();

Update

Update() updates the channel membership information for a given user.

Method signature

Blueprint

C++ / Input parameters

Membership->Update(FString CustomData);

Parameter	Type	Required	Default	Description
Custom	FString	Yes	n/a	Any custom properties or metadata associated with the channel-user membership.

Output

Type	Description
UPubnubMembership*	Returned (modified) object containing all membership data.

Basic usage

Assign the premium-support role to support_agent_15 on the high-priority-incidents channel.

#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");

// Define user ID
FString UserID = "support_agent_15";

// Get the user and save the reference
UPubnubUser* User = Chat->GetUser(UserID);

// Define user ID

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