PubNub MCP Server

# PubNub Unreal SDK – Publish / Subscribe (Condensed) This short reference keeps every method signature, struct definition, enum, parameter, limit, and code example from the original docs. Redundant prose has been removed. --- ## Publish Requirements & limits • App must be initialized with a `publishKey` • Sender needn’t be subscribed to the channel • One channel per call (no multi-channel publish) • Payload: any JSON-serializable type; **don’t pre-serialize** `message` or `meta` • Max size = 32 KiB (URI + channel + escaped JSON). Optimal < 1800 bytes • Publish serially: next message only after success. Memory queue = 100 messages • Throttle bursts (≈ ≤ 5 msg/s) to avoid drops ### Method ``` `PubnubSubsystem->PublishMessage( FString Channel, FString Message, FPubnubPublishSettings PublishSettings = FPubnubPublishSettings() ); ` ``` ### FPubnubPublishSettings * StoreInHistory (bool, default true) – include in storage/History API * MetaData (FString) – JSON object used by server-side filters * PublishMethod (EPubnubPublishMethod) - `PPM_SendViaGET` - `PPM_SendViaPOST` - `PPM_UsePATCH` - `PPM_SendViaPOSTwithGZIP` - `PPM_UsePATCHwithGZIP` - `PPM_UseDELETE` * Replicate (bool) – false ⇒ only Functions receive the message * CustomMessageType (FString 3-50 chars, a-z A-Z 0-9 - _) – e.g. `text`, `action` ### Examples #### Minimal publish ``` `// NOTE: This example requires correct PubnubSDK configuration … #pragma once … class MYPROJECT_API AMyGameMode : public AGameModeBase ` ``` ``` `#include "MyGameMode.h" #include "PubnubSubsystem.h" #include "Kismet/GameplayStatics.h" void AMyGameMode::PublishMessageExample() { UGameInstance* GameInstance = UGameplayStatics::GetGameInstance(this); UPubnubSubsystem* PubnubSubsystem = GameInstance->GetSubsystemUPubnubSubsystem>(); PubnubSubsystem->SetUserID("my_user_id"); FString Channel = "randomChannel"; FString Message = "{ \"text\" : \"This is my message\" }"; ` ``` #### POST + GZIP ``` `#include "Kismet/GameplayStatics.h" #include "PubnubSubsystem.h" UGameInstance* GameInstance = UGameplayStatics::GetGameInstance(this); UPubnubSubsystem* PubnubSubsystem = GameInstance->GetSubsystemUPubnubSubsystem>(); FString Channel = "randomChannel"; FString Message = "{ \"text\" : \"This is my message\" }"; FPubnubPublishSettings PublishSettings; PublishSettings.PublishMethod = EPubnubPublishMethod::PPM_SendViaPOSTwithGZIP; PubnubSubsystem->PublishMessage(Channel, Message, PublishSettings); ` ``` (Return: none. Check listener for ACK: `[1,"Sent", "<timetoken>"]`) --- ## Signal • Same semantics as Publish, but payload limit **64 bytes** (payload only) ### Method ``` `PubnubSubsystem->Signal( FString Channel, FString Message, FPubnubSignalSettings SignalSettings = FPubnubSignalSettings() ); ` ``` ### FPubnubSignalSettings * CustomMessageType (FString) – same rules as above ### Example ``` `#include "Kismet/GameplayStatics.h" #include "PubnubSubsystem.h" UGameInstance* GameInstance = UGameplayStatics::GetGameInstance(this); UPubnubSubsystem* PubnubSubsystem = GameInstance->GetSubsystemUPubnubSubsystem>(); FString Channel = "randomChannel"; FString Message = "{ \"text\" : \"This is my signal\" }"; FPubnubSignalSettings SignalSettings; PublishSettings.CustomMessageType = "text-message"; PubnubSubsystem->Signal(Channel, Message, SignalSettings); ` ``` (Return: none) --- ## Subscribe Key points • Requires `subscribeKey` at initialization • Opens a long-lived socket; receive via event listeners • Add listeners *before* calling subscribe • Unsubscribing from **all** channels resets the timetoken (possible gaps) ### Methods ``` `// subscribe to a channel PubnubSubsystem->SubscribeToChannel(FString Channel, FPubnubSubscriptionSettinngs SubscriptionSettings); // subscribe to a channel group PubnubSubsystem->SubscribeToGroup(FString GroupName, FPubnubSubscriptionSettinngs SubscriptionSettings); ` ``` ### FPubnubSubscriptionSettings * ReceivePresenceEvents (bool) – true ⇒ presence events for this channel ### Basic subscribe ``` `#include "Kismet/GameplayStatics.h" #include "PubnubSubsystem.h" UGameInstance* GameInstance = UGameplayStatics::GetGameInstance(this); UPubnubSubsystem* PubnubSubsystem = GameInstance->GetSubsystemUPubnubSubsystem>(); FString Channel = "randomChannel"; PubnubSubsystem->SubscribeToChannel(Channel, SubscriptionSettings); ` ``` ### Presence subscribe (Presence add-on required) ``` `… FPubnubSubscriptionSettings SubscriptionSettings; SubscriptionSettings.ReceivePresenceEvents = true; PubnubSubsystem->SubscribeToChannel(Channel, SubscriptionSettings); ` ``` ### Wildcard subscribe (Stream Controller add-on) ``` `… FString Channel = "foo.*"; PubnubSubsystem->Subscribe(Channel); ` ``` (Return: none – events arrive through listener) --- ## Unsubscribe ### Methods ``` `// unsubscribe from a channel PubnubSubsystem->UnsubscribeFromChannel(FString Channel); // unsubscribe from a channel group PubnubSubsystem->UnsubscribeFromGroup(FString GroupName); ` ``` ### Sample ``` `… PubnubSubsystem->Subscribe(Channel); PubnubSubsystem->SubscribeToGroup(ChannelGroupName); PubnubSubsystem->UnsubscribeFromChannel(Channel); ` ``` (Return: none) --- ## Unsubscribe All ### Method ``` `PubnubSubsystem->UnsubscribeFromAll(); ` ``` ### Sample ``` `… PubnubSubsystem->Subscribe(Channel); PubnubSubsystem->SubscribeToGroup(ChannelGroupName); PubnubSubsystem->UnsubscribeFromAll(); ` ``` (Return: none) _Last updated: Jul 15 2025_