Configuration API for PubNub Unreal SDK

Unreal complete API reference for building real-time applications on PubNub, including basic usage and sample code.

Configuration and Initialization​

You can configure the PubNub SDK in Unreal Editor as follows:

  1. In the Unreal Editor window, click the Settings dropdown and select Project Settings.

  2. In the Project Settings window, scroll down to the Plugins section and click Pubnub SDK. The Plugins - Pubnub SDK view opens.

  3. In the Plugins - Pubnub SDK view, provide the desired values for the available configuration options.

Open project settings

PropertyTypeRequiredDescription
Publish KeystringOptionalPublish Key from Admin Portal (only required if publishing).
Subscribe KeystringYesSubscribe Key from Admin Portal.
Secret KeystringOptionalSecret Key from Admin Portal, only required for access control operations.
Initialize AutomaticallyBooleanOptionalWhether to initialize the SDK without having to invoke the Init Pubnub command.
Set Secret Key AutomaticallyBooleanOptionalWhether to initialize the SDK with the provided secret key without having to invoke the Set Secret Key command.

Basic Usage​

Required User ID

Always set the User ID to uniquely identify the user or device that connects to PubNub. This User ID should be persisted, and should remain unchanged for the lifetime of the user or the device. If you don't set the User ID, you won't be able to connect to PubNub.

Config in Project Settings

Event Listeners​

In PubNub Unreal SDK, the listeners notify you of message events and errors. All events emitted on a particular channel are received through OnMessageReceived but differ in their JSON payload. Refer to Event types for more information.

Add Listeners​

Add Callback Function​

Responses to functions are handled using response delegates and callback functions.

All functions that take a parameter of the FOnPubnubResponse type need a callback function to handle the response. Let's look into an example implementation of a callback function for the ListUsersFromChannel function.

Event Types​

All message events are routed through OnMessageReceived but have a different JSON structure. The following list shows examples of the event payload emitted for different event types.

Objects​

Set UUID Metadata​

{
  "source": "objects",
  "version": "2.0",
  "event": "set",
  "type": "uuid",
  "data": {
    "eTag": "dad3f3d77ec74a6458b34e0ee5172544",
    "id": "User1",
    "name": "new name",
    "updated": "2024-08-12T06:37:16.441347Z"
  }
}

Set Channel Metadata​

{
  "source": "objects",
  "version": "2.0",
  "event": "set",
  "type": "channel",
  "data": {
    "eTag": "cdfd462ffc3a985470fd309810a05f0b",
    "id": "my_channel2",
    "name": "new channel name",
    "updated": "2024-08-12T06:39:50.16522Z"
  }
}

Set Member​

{
  "source": "objects",
  "version": "2.0",
  "event": "set",
  "type": "membership",
  "data": {
    "channel": {
      "id": "my_ue_channel"
    },
    "eTag": "Afah2qS199e74QE",
    "updated": "2024-08-12T13:15:47.057904689Z",
    "uuid": {
      "id": "User11"
    }
  }
show all 16 lines

Set Membership​

{
  "source": "objects",
  "version": "2.0",
  "event": "set",
  "type": "membership",
  "data": {
    "channel": {
      "id": "channel_from_ue"
    },
    "eTag": "Afah2qS199e74QE",
    "updated": "2024-08-12T13:17:22.756243015Z",
    "uuid": {
      "id": "User12"
    }
  }
show all 16 lines

Presence​

Presence Join​

{
    "Event": "join",
    "Uuid": "175c2c67-b2a9-470d-8f4b-1db94f90e39e",
    "Timestamp": 1345546797,
    "Occupancy": 2,
    "State": null,
    "Channel":" my_channel",
    "Subscription": "",
    "Timetoken": 15034141109823424,
    "UserMetadata": null,
    "Join": null,
    "Timeout": null,
    "Leave": null,
    "HereNowRefresh": false
}

Presence Leave​

{
    "Event": "leave",
    "Uuid": "175c2c67-b2a9-470d-8f4b-1db94f90e39e",
    "Timestamp": 1345546797,
    "Occupancy": 1,
    "State": null,
    "Channel": "my_channel",
    "Subscription": "",
    "Timetoken": 15034141109823424,
    "UserMetadata": null,
    "Join": null,
    "Timeout": null,
    "Leave": null,
    "HereNowRefresh": false
}

Presence Timeout​

{
    "Event": "timeout",
    "Uuid": "175c2c67-b2a9-470d-8f4b-1db94f90e39e",
    "Timestamp": 1345546797,
    "Occupancy": 0,
    "State": null,
    "Channel": "my_channel",
    "Subscription": "",
    "Timetoken": 15034141109823424,
    "UserMetadata": null,
    "Join": null,
    "Timeout": null,
    "Leave": null,
    "HereNowRefresh": false
}

Custom Presence Event (State Change)​

{
    "Event": "state-change",
    "Uuid": "175c2c67-b2a9-470d-8f4b-1db94f90e39e",
    "Timestamp": 1345546797,
    "Occupancy": 1,
    "State": {
        "isTyping": true
    },
    "Channel": "my_channel",
    "Subscription": "",
    "Timetoken": 15034141109823424,
    "UserMetadata": null,
    "Join": null,
    "Timeout": null,
    "Leave": null,
show all 17 lines

Presence Interval​

{
    "Event": "interval",
    "Uuid": "175c2c67-b2a9-470d-8f4b-1db94f90e39e",
    "Timestamp": 1345546797,
    "Occupancy": 2,
    "State": null,
    "Channel": "my_channel",
    "Subscription": "",
    "Timetoken": 15034141109823424,
    "UserMetadata": null,
    "Join": null,
    "Timeout": null,
    "Leave": null,
    "HereNowRefresh": false
}

When a channel is in interval mode with presence_deltas pnconfig flag enabled, the interval message may also include the following fields which contain an array of changed UUIDs since the last interval message.

  • joined
  • left
  • timedout

For example, this interval message indicates there were 2 new User IDs that joined and 1 timed out User ID since the last interval:

{
    "Event": "interval",
    "Uuid": "175c2c67-b2a9-470d-8f4b-1db94f90e39e",
    "Timestamp": <unix timestamp>,
    "Occupancy": <# users in channel>,
    "State": null,
    "Channel": "my_channel",
    "Subscription": "",
    "Timetoken": 15034141109823424,
    "UserMetadata": null,
    "Join": ["uuid2", "uuid3"],
    "Timeout": ["uuid1"],
    "Leave": null,
    "HereNowRefresh": false
}

If the full interval message is greater than 30KB (since the max publish payload is ∼32KB), none of the extra fields will be present. Instead there will be a here_now_refresh boolean field set to true. This indicates to the user that they should do a hereNow request to get the complete list of users present in the channel.

{
    "Event": "interval",
    "Uuid": "175c2c67-b2a9-470d-8f4b-1db94f90e39e",
    "Timestamp": <unix timestamp>,
    "Occupancy": <# users in channel>,
    "State": null,
    "Channel": "my_channel",
    "Subscription": "",
    "Timetoken": 15034141109823424,
    "UserMetadata": null,
    "Join": null,
    "Timeout": null,
    "Leave": null,
    "HereNowRefresh": true
}
Last updated on
On this page