Channel Groups API for Unreal SDK

Channel groups allow PubNub developers to bundle thousands of channels into a group that can be identified by a name. These channel groups can then be subscribed to, receiving data from the many back-end channels the channel group contains.

Channel group operations

You can't publish to a channel group. You can only subscribe to it. To publish within the channel group, you need to publish to each channel individually.

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

• In Blueprints, the SDK is managed by a subsystem. Start by calling the Pubnub Subsystem node, then use Create Pubnub Client to create a UPubnubClient instance.

• In a C++ project, you have to add a dependency to PubnubLibrary:

  1. In your IDE, navigate to Source/_{YourProject}_/_{YourProject}_.Build.cs and add a dependency to PubnubLibrary.

     PrivateDependencyModuleNames.AddRange(new string[] { "PubnubLibrary" });

  2. Compile the code and run the project.

• In C++, start by getting the UPubnubSubsystem (a Game Instance Subsystem), then create a UPubnubClient with your configuration.

  #include "Kismet/GameplayStatics.h"
  #include "PubnubSubsystem.h"
  #include "PubnubClient.h"
  
  
  UGameInstance* GameInstance = UGameplayStatics::GetGameInstance(this);
  UPubnubSubsystem* PubnubSubsystem = GameInstance->GetSubsystem<UPubnubSubsystem>();
  
  
  FPubnubConfig Config;
  Config.PublishKey = "pub-c-...";
  Config.SubscribeKey = "sub-c-...";
  Config.UserId = "my-user-id";
  
  
  UPubnubClient* PubnubClient = PubnubSubsystem->CreatePubnubClient(Config);

  PubnubClient allows you to call PubNub SDK functions, for example:

  PubnubClient->PublishMessageAsync("my-channel", "Hello!", OnPublishMessageResponseDelegate);

  The SDK supports multiple UPubnubClient instances within the same game for different contexts such as different users or keysets. For more information, refer to Configuration.

Usage in Blueprints and C++

Asynchronous and synchronous method execution

Most PubNub Unreal SDK methods are available in both asynchronous and synchronous variants.

• Asynchronous methods (Async suffix) return void and take an optional delegate parameter that fires when the operation completes.

  1PubnubClient->AddChannelToGroupAsync("my-channel", "my-group", OnAddChannelToGroupResponseDelegate);

  You can also use native callbacks that accept lambdas instead of dynamic delegates. Native callback types have the Native suffix (for example, FOnPubnubAddChannelToGroupResponseNative).

• Synchronous methods (no suffix) block the main game thread until the operation completes and return a result struct directly.

  1FPubnubOperationResult Result = PubnubClient->AddChannelToGroup("my-channel", "my-group");

Add channels to a channel group

Requires Stream Controller add-on

This method requires the Stream Controller add-on enabled for your key in the Admin Portal. Read the support page on enabling add-on features.

This function adds a channel to a channel group. You can call AddChannelToGroup() on a ChannelGroup entity (which already knows its channel group) or directly on the PubNub client by passing the channel group name explicitly.

Maximum number of channels

You can add up to 200 channels to a channel group per API call.

ChannelGroup entity

This method is available to use with the ChannelGroup entity. For more information, refer to ChannelGroup.

Available in entities

ChannelGroup

Method(s)

1UPubnubChannelGroupEntity* ChannelGroupEntity = PubnubSubsystem->CreateChannelGroupEntity("my-channel-group");
2

3ChannelGroupEntity->AddChannelToGroup(
4    FString Channel,
5    FOnAddChannelToGroupResponse OnAddChannelToGroupResponse
6);

* required

Parameter	Description
Channel * Type: FString	The channel to add to the channel group.
OnAddChannelToGroupResponse * Type: FOnAddChannelToGroupResponse	The delegate for the operation's result. You can also use a native callback of the type FOnAddChannelToGroupResponseNative to handle the result using a lambda.

FOnAddChannelToGroupResponse

Field	Type	Description
Result	FPubnubOperationResult	The operation result.

FOnAddChannelToGroupResponseNative

Field	Type	Description
Result	const FPubnubOperationResult&	The operation result.

Sample code

Reference code

Set up your Unreal project and follow the instructions in the lines marked with ACTION REQUIRED before running the code.

C++

Actor.h

1

Actor.cpp

1

Returns

This method is void, but the delegate returns the FOnAddChannelToGroupResponse struct.

Other Examples

Reference code

Set up your Unreal project and follow the instructions in the lines marked with ACTION REQUIRED before running the code.

Add channels to a channel group with lambda

Use a lambda function to handle the response:

Actor.h

1

Actor.cpp

1

Add channels to a channel group with result struct

Use the result struct to handle the response:

Actor.h

1

Actor.cpp

1

PubNub client

Method(s)

1PubnubClient->AddChannelToGroupAsync(
2    FString Channel,
3    FString ChannelGroup,
4    FOnPubnubAddChannelToGroupResponse OnAddChannelToGroupResponse
5);

* required

Parameter	Description
Channel * Type: FString	The channel to add to the channel group.
ChannelGroup * Type: FString	The channel group to add the channels to.
OnAddChannelToGroupResponse * Type: FOnPubnubAddChannelToGroupResponse	The delegate for the operation's result. You can also use a native callback of the type FOnPubnubAddChannelToGroupResponseNative to handle the result using a lambda.

Sample code

Reference code

Set up your Unreal project and follow the instructions in the lines marked with ACTION REQUIRED before running the code.

C++

Actor.h

1

Actor.cpp

1

Blueprint

Returns

This method is void. The delegate returns the following struct:

FOnPubnubAddChannelToGroupResponse

Delegate type: DECLARE_DYNAMIC_DELEGATE_OneParam

Parameter	Description
Result Type: FPubnubOperationResult	The operation result.

FOnPubnubAddChannelToGroupResponseNative

Native callback variant that accepts a lambda.

Parameter	Description
Result Type: const FPubnubOperationResult&	The operation result.

Other Examples

Reference code

Set up your Unreal project and follow the instructions in the lines marked with ACTION REQUIRED before running the code.

Add channels to a channel group with lambda

Use a lambda function to handle the response:

Actor.h

1

Actor.cpp

1

Add channels to a channel group with result struct

Use the result struct to handle the response:

Actor.h

1

Actor.cpp

1

List channels in a channel group

Requires Stream Controller add-on

This method requires the Stream Controller add-on enabled for your key in the Admin Portal. Read the support page on enabling add-on features.

This function lists all channels in the channel group. You can call ListChannelsFromGroup() on a ChannelGroup entity (which already knows its channel group) or directly on the PubNub client by passing the channel group name explicitly.

ChannelGroup entity

This method is available to use with the ChannelGroup entity. For more information, refer to ChannelGroup.

Available in entities

ChannelGroup

Method(s)

1UPubnubChannelGroupEntity* ChannelGroupEntity = PubnubSubsystem->CreateChannelGroupEntity("my-channel-group");
2

3ChannelGroupEntity->ListChannelsFromGroup(
4    FOnListChannelsFromGroupResponse OnListChannelsResponse
5);

* required

Parameter	Description
OnListChannelsResponse * Type: FOnListChannelsFromGroupResponse	The operation result delegate. You can also use FOnListChannelsFromGroupResponseNative with a lambda.

FOnListChannelsFromGroupResponse

Field	Type	Description
Result	FPubnubOperationResult	The operation result.
Channels	TArray<FString>&	Channel names in the group.

FOnListChannelsFromGroupResponseNative

Field	Type	Description
Result	const FPubnubOperationResult&	The operation result.
Channels	const TArray<FString>&	Channel names in the group.

Sample code

Reference code

Set up your Unreal project and follow the instructions in the lines marked with ACTION REQUIRED before running the code.

C++

Actor.h

1

Actor.cpp

1

Returns

This function is void, but the delegate returns the FOnListChannelsFromGroupResponse struct.

Other Examples

Reference code

Set up your Unreal project and follow the instructions in the lines marked with ACTION REQUIRED before running the code.

List channels from a channel group with lambda

Use a lambda function to handle the response:

Actor.h

1

Actor.cpp

1

List channels from a channel group with result struct

Use the result struct to handle the response:

Actor.h

1

Actor.cpp

1

PubNub client

Method(s)

1PubnubClient->ListChannelsFromGroupAsync(
2    FString ChannelGroup,
3    FOnPubnubListChannelsFromGroupResponse OnListChannelsResponse
4);

* required

Parameter	Description
ChannelGroup * Type: FString	The channel group to list channels of.
OnListChannelsResponse * Type: FOnPubnubListChannelsFromGroupResponse	The operation result delegate. You can also use FOnPubnubListChannelsFromGroupResponseNative with a lambda.

Sample code

Reference code

Set up your Unreal project and follow the instructions in the lines marked with ACTION REQUIRED before running the code.

C++

Actor.h

1

Actor.cpp

1

Blueprint

Returns

This method is void. The delegate returns the following struct:

FOnPubnubListChannelsFromGroupResponse

Delegate type: DECLARE_DYNAMIC_DELEGATE_TwoParams

Parameter	Description
Result Type: FPubnubOperationResult	The operation result.
Channels Type: const TArray<FString>&	Channel names in the group.

FOnPubnubListChannelsFromGroupResponseNative

Native callback variant that accepts a lambda.

Parameter	Description
Result Type: const FPubnubOperationResult&	The operation result.
Channels Type: const TArray<FString>&	Channel names in the group.

Other Examples

Reference code

Set up your Unreal project and follow the instructions in the lines marked with ACTION REQUIRED before running the code.

List channels from a channel group with lambda

Use a lambda function to handle the response:

Actor.h

1

Actor.cpp

1

Remove channels from a channel group

Requires Stream Controller add-on

This method requires the Stream Controller add-on enabled for your key in the Admin Portal. Read the support page on enabling add-on features.

This function removes channels from the channel group. You can call RemoveChannelFromGroup() on a ChannelGroup entity (which already knows its channel group) or directly on the PubNub client by passing the channel group name explicitly.

ChannelGroup entity

This method is available to use with the ChannelGroup entity. For more information, refer to ChannelGroup.

Available in entities

ChannelGroup

Method(s)

1UPubnubChannelGroupEntity* ChannelGroupEntity = PubnubSubsystem->CreateChannelGroupEntity("my-channel-group");
2

3ChannelGroupEntity->RemoveChannelFromGroup(
4    FString Channel,
5    FOnRemoveChannelFromGroupResponse OnRemoveChannelFromGroupResponse
6);

* required

Parameter	Description
Channel * Type: FString	The channel to remove from the channel group.
OnRemoveChannelFromGroupResponse * Type: FOnRemoveChannelFromGroupResponse	The operation result delegate. You can also use FOnRemoveChannelFromGroupResponseNative with a lambda.

FOnRemoveChannelFromGroupResponse

Field	Type	Description
Result	FPubnubOperationResult	The operation result.

FOnRemoveChannelFromGroupResponseNative

Field	Type	Description
Result	const FPubnubOperationResult&	The operation result.

Sample code

Reference code

Set up your Unreal project and follow the instructions in the lines marked with ACTION REQUIRED before running the code.

C++

Actor.h

1

Actor.cpp

1

Returns

This method is void, but the delegate returns the FOnRemoveChannelFromGroupResponse struct.

Other Examples

Reference code

Set up your Unreal project and follow the instructions in the lines marked with ACTION REQUIRED before running the code.

Remove channels from a channel group with lambda

Use a lambda function to handle the response:

Actor.h

1

Actor.cpp

1

Remove channels from a channel group with result struct

Use the result struct to handle the response:

Actor.h

1

Actor.cpp

1

PubNub client

Method(s)

1PubnubClient->RemoveChannelFromGroupAsync(
2    FString Channel,
3    FString ChannelGroup,
4    FOnPubnubRemoveChannelFromGroupResponse OnRemoveChannelFromGroupResponse
5);

* required

Parameter	Description
Channel * Type: FString	The channel to remove from the channel group.
ChannelGroup * Type: FString	The channel group to remove the channel from.
OnRemoveChannelFromGroupResponse * Type: FOnPubnubRemoveChannelFromGroupResponse	The operation result delegate. You can also use FOnPubnubRemoveChannelFromGroupResponseNative with a lambda.

Sample code

Reference code

Set up your Unreal project and follow the instructions in the lines marked with ACTION REQUIRED before running the code.

C++

Actor.h

1

Actor.cpp

1

Blueprint

Returns

This method is void. The delegate returns the following struct:

FOnPubnubRemoveChannelFromGroupResponse

Delegate type: DECLARE_DYNAMIC_DELEGATE_OneParam

Parameter	Description
Result Type: FPubnubOperationResult	The operation result.

FOnPubnubRemoveChannelFromGroupResponseNative

Native callback variant that accepts a lambda.

Parameter	Description
Result Type: const FPubnubOperationResult&	The operation result.

Other Examples

Reference code

Set up your Unreal project and follow the instructions in the lines marked with ACTION REQUIRED before running the code.

Remove channels from a channel group with lambda

Use a lambda function to handle the response:

Actor.h

1

Actor.cpp

1

Remove channels from a channel group with result struct

Use the result struct to handle the response:

Actor.h

1

Actor.cpp

1

Delete a channel group

Requires Stream Controller add-on

This method requires the Stream Controller add-on enabled for your key in the Admin Portal. Read the support page on enabling add-on features.

This function removes a channel group. You can call RemoveChannelGroup() on a ChannelGroup entity (which already knows its channel group) or directly on the PubNub client by passing the channel group name explicitly.

ChannelGroup entity

This method is available to use with the ChannelGroup entity. For more information, refer to ChannelGroup.

Available in entities

ChannelGroup

Method(s)

1UPubnubChannelGroupEntity* ChannelGroupEntity = PubnubSubsystem->CreateChannelGroupEntity("my-channel-group");
2

3ChannelGroupEntity->RemoveChannelGroup(
4    FOnRemoveChannelGroupResponse OnRemoveChannelGroupResponse
5);

* required

Parameter	Description
OnRemoveChannelGroupResponse * Type: FOnRemoveChannelGroupResponse	The operation result delegate. You can also use FOnRemoveChannelGroupResponseNative with a lambda.

FOnRemoveChannelGroupResponse

Field	Type	Description
Result	FPubnubOperationResult	The operation result.

FOnRemoveChannelGroupResponseNative

Field	Type	Description
Result	const FPubnubOperationResult&	The operation result.

Sample code

Reference code

Set up your Unreal project and follow the instructions in the lines marked with ACTION REQUIRED before running the code.

C++

Actor.h

1

Actor.cpp

1

Returns

This method is void, but the delegate returns the FOnRemoveChannelGroupResponse struct.

Other Examples

Reference code

Set up your Unreal project and follow the instructions in the lines marked with ACTION REQUIRED before running the code.

Delete a channel group with lambda

Use a lambda function to handle the response:

Actor.h

1

Actor.cpp

1

Delete a channel group with result struct

Use the result struct to handle the response:

Actor.h

1

Actor.cpp

1

PubNub client

Method(s)

1PubnubClient->RemoveChannelGroupAsync(
2    FString ChannelGroup,
3    FOnPubnubRemoveChannelGroupResponse OnRemoveChannelGroupResponse
4);

* required

Parameter	Description
ChannelGroup * Type: FString	The channel group to remove.
OnRemoveChannelGroupResponse * Type: FOnPubnubRemoveChannelGroupResponse	The operation result delegate. You can also use FOnPubnubRemoveChannelGroupResponseNative with a lambda.

Sample code

Reference code

Set up your Unreal project and follow the instructions in the lines marked with ACTION REQUIRED before running the code.

C++

Actor.h

1

Actor.cpp

1

Blueprint

Returns

This method is void. The delegate returns the following struct:

FOnPubnubRemoveChannelGroupResponse

Delegate type: DECLARE_DYNAMIC_DELEGATE_OneParam

Parameter	Description
Result Type: FPubnubOperationResult	The operation result.

FOnPubnubRemoveChannelGroupResponseNative

Native callback variant that accepts a lambda.

Parameter	Description
Result Type: const FPubnubOperationResult&	The operation result.

Other Examples

Reference code

Set up your Unreal project and follow the instructions in the lines marked with ACTION REQUIRED before running the code.

Delete a channel group with lambda

Use a lambda function to handle the response:

Actor.h

1

Actor.cpp

1

Delete a channel group with result struct

Use the result struct to handle the response:

Actor.h

1

Actor.cpp

1

Complete example

Reference code

Set up your Unreal project and follow the instructions in the lines marked with ACTION REQUIRED before running the code.

ASample_GroupsFull.h

1

ASample_GroupsFull.cpp

1

Deprecated methods

Add channels to a channel group (deprecated)

Deprecated

Use PubnubClient->AddChannelToGroup() (synchronous) or PubnubClient->AddChannelToGroupAsync() (asynchronous) instead.

Method(s) (deprecated)

1PubnubSubsystem->AddChannelToGroup(
2    FString Channel,
3    FString ChannelGroup,
4    FOnAddChannelToGroupResponse OnAddChannelToGroupResponse
5);

* required

Parameter	Description
Channel * Type: FString	The channel to add to the channel group.
ChannelGroup * Type: FString	The channel group to add the channels to.
OnAddChannelToGroupResponse * Type: FOnAddChannelToGroupResponse	The delegate for the operation's result.

Returns (deprecated)

This method doesn't return a value.

List channels in a channel group (deprecated)

Deprecated

Use PubnubClient->ListChannelsFromGroup() (synchronous) or PubnubClient->ListChannelsFromGroupAsync() (asynchronous) instead.

Method(s) (deprecated)

1PubnubSubsystem->ListChannelsFromGroup(
2    FString ChannelGroup,
3    FOnListChannelsFromGroupResponse OnListChannelsResponse
4);

* required

Parameter	Description
ChannelGroup * Type: FString	The channel group to list channels of.
OnListChannelsResponse * Type: FOnListChannelsFromGroupResponse	The operation result delegate.

Returns (deprecated)

This function is void, but the delegate returns the FOnListChannelsFromGroupResponse struct.

Field	Type	Description
Result	FPubnubOperationResult	The operation result.
Channels	TArray<FString>&	Channel names in the group.

Remove channels from a channel group (deprecated)

Deprecated

Use PubnubClient->RemoveChannelFromGroup() (synchronous) or PubnubClient->RemoveChannelFromGroupAsync() (asynchronous) instead.

Method(s) (deprecated)

1PubnubSubsystem->RemoveChannelFromGroup(
2    FString Channel,
3    FString ChannelGroup,
4    FOnRemoveChannelFromGroupResponse OnRemoveChannelFromGroupResponse
5);

* required

Parameter	Description
Channel * Type: FString	The channel to remove from the channel group.
ChannelGroup * Type: FString	The channel group to remove the channel from.
OnRemoveChannelFromGroupResponse * Type: FOnRemoveChannelFromGroupResponse	The operation result delegate.

Returns (deprecated)

This method doesn't return a value.

Delete a channel group (deprecated)

Deprecated

Use PubnubClient->RemoveChannelGroup() (synchronous) or PubnubClient->RemoveChannelGroupAsync() (asynchronous) instead.

Method(s) (deprecated)

1PubnubSubsystem->RemoveChannelGroup(
2    FString ChannelGroup,
3    FOnRemoveChannelGroupResponse OnRemoveChannelGroupResponse
4);

* required

Parameter	Description
ChannelGroup * Type: FString	The channel group to remove.
OnRemoveChannelGroupResponse * Type: FOnRemoveChannelGroupResponse	The operation result delegate.

Returns (deprecated)

This method doesn't return a value.