Online Subsystem Blueprintable - Setup Guide

This guide walks you through setting up Online Subsystem Blueprintable for your project, including platform-specific configuration for Steam and Epic Online Services.

Basic Installation

1. Download the Plugin

   Get the latest version from your Dashboard

2. Install to Project

   Extract to YourProject/Plugins/OnlineSubsystemBlueprintable/

3. Enable Required Plugins

   In Edit → Plugins, enable:

   • Online Subsystem Blueprintable
   • Online Subsystem (if not already enabled)
   • Your target platform plugin (e.g., Online Subsystem Steam)

4. Activate License

   Go to Edit → Project Settings → Plugins → gameDNA Online Subsystem Blueprintable Enter your license key and click Activate

5. Restart Editor

   Restart Unreal Editor to ensure all modules load correctly

Project Configuration

DefaultEngine.ini

Add platform configuration to Config/DefaultEngine.ini:

Steam

[OnlineSubsystem]
DefaultPlatformService=Steam

[OnlineSubsystemSteam]
bEnabled=true
SteamDevAppId=480
; Replace 480 with your actual Steam App ID for production

[/Script/OnlineSubsystemSteam.SteamNetDriver]
NetConnectionClassName="OnlineSubsystemSteam.SteamNetConnection"

Epic Online Services

[OnlineSubsystem]
DefaultPlatformService=EOS

[OnlineSubsystemEOS]
bEnabled=true

[/Script/OnlineSubsystemEOS.EOSSettings]
ProductId=YOUR_PRODUCT_ID
SandboxId=YOUR_SANDBOX_ID
DeploymentId=YOUR_DEPLOYMENT_ID
ClientId=YOUR_CLIENT_ID
ClientSecret=YOUR_CLIENT_SECRET

Multi-Platform

[OnlineSubsystem]
; Don't set default - we'll choose at runtime
; DefaultPlatformService=

[OnlineSubsystemSteam]
bEnabled=true
SteamDevAppId=480

[OnlineSubsystemEOS]
bEnabled=true

; Plugin-specific settings
[OnlineSubsystemBlueprintable]
bAllowRuntimeSwitch=true
DefaultSubsystem=Steam
FallbackSubsystem=EOS

Steam Setup

Prerequisites

• Steam account with Steamworks access
• Steam App ID (use 480 for testing)
• Steamworks SDK (included with UE Steam plugin)

Step-by-Step Setup

1. Get Steam App ID

   • For testing: Use 480 (Spacewar test app)
   • For production: Create app at partner.steamgames.com

2. Configure Steam Settings

   In Config/DefaultEngine.ini:

   [OnlineSubsystemSteam]
   bEnabled=true
   SteamDevAppId=480
   bRelaunchInSteam=false
   SteamAppId=480
   GameServerQueryPort=27015
   bVACEnabled=true
   GameVersion=1.0.0.0

3. Create steam_appid.txt

   Create steam_appid.txt in your project root containing just your App ID:

   480

4. Configure Achievements (Optional)

   In Steamworks dashboard, define your achievements. The plugin will query them at runtime.

5. Test Connection

   Create a test Blueprint:

   Event BeginPlay
   → Initialize Online Subsystem (Platform: "Steam")
   → Print: Is Initialized

   Run with Steam client open. Should print “true”.

Caution

Steam requires the Steam client to be running for the Online Subsystem to work. In packaged builds, your game must be launched through Steam.

Steam-Specific Nodes

Node	Description
Get Steam ID	Returns the local player’s Steam ID
Get Steam Persona Name	Returns the Steam display name
Open Steam Overlay	Opens Steam overlay to a specific page
Get Steam Avatar	Returns player’s Steam avatar as texture
Is Steam Running	Checks if Steam client is active

Epic Online Services Setup

Prerequisites

• Epic Games account
• EOS Developer Portal access
• Product, Sandbox, and Deployment configured

Step-by-Step Setup

1. Create EOS Product

   Visit dev.epicgames.com/portal

   • Create new product
   • Note your Product ID, Sandbox ID, Deployment ID
   • Create a Client under Product Settings

2. Configure Credentials

   In Config/DefaultEngine.ini:

   [OnlineSubsystemEOS]
   bEnabled=true
   
   [/Script/OnlineSubsystemEOS.EOSSettings]
   ProductId=prod_xxxxxxxxxxxxxxxx
   SandboxId=sandbox_xxxxxxxxxxxxxxxx
   DeploymentId=deploy_xxxxxxxxxxxxxxxx
   ClientId=xyza7891234567890abcdef
   ClientSecret=your-client-secret-here
   
   ; Auth scopes
   ScopeFlags=BasicProfile,FriendsList,Presence

3. Configure Login Methods

   In EOS Developer Portal, enable desired login methods:

   • Epic Account (Epic Games Launcher users)
   • Device ID (anonymous, great for initial testing)
   • External (Steam, PlayStation, etc.)

4. Test Connection

   Create a test Blueprint:

   Event BeginPlay
   → Initialize Online Subsystem (Platform: "EOS")
   → Login with Device ID
   → On Success: Print "EOS Connected!"

EOS-Specific Nodes

Node	Description
Login with Epic Account	OAuth login via Epic
Login with Device ID	Anonymous device-based login
Login with External	Login using Steam/console credentials
Get EOS Product User ID	Returns the PUID
Get EOS Epic Account ID	Returns Epic account ID if linked

Runtime Platform Switching

One powerful feature is switching platforms at runtime:

// Check available platforms
Get Available Online Subsystems
→ For Each: Print Platform Name

// Switch to a different platform
Switch Online Subsystem (New Platform: "EOS")
→ On Success:
    → Login with appropriate method
→ On Failure:
    → Print Error Message

Tip

Use runtime switching to support multiple platforms from a single build, or to allow users to choose their preferred login method.

Blueprint Setup

Creating a Login Manager

1. Create Blueprint

   Content Browser → Blueprint Class → Actor → Name: BP_OnlineManager

2. Add Variables

   • IsInitialized (Boolean)
   • IsLoggedIn (Boolean)
   • CurrentUserId (String)
   • CurrentDisplayName (String)

3. Initialize on Begin Play

   Event BeginPlay
   → Initialize Online Subsystem
     → Bind: On Initialize Complete
   
   On Initialize Complete (Success)
   → Set IsInitialized = Success
   → Branch: Success?
     → True: Call Custom Event "DoLogin"
     → False: Print "Failed to initialize: " + Error

4. Create Login Function

   Custom Event: DoLogin
   → Login With Platform Credentials
     → Bind: On Login Complete
   
   On Login Complete (Success, UserId, Error)
   → Set IsLoggedIn = Success
   → Branch: Success?
     → True:
       → Set CurrentUserId = UserId
       → Get Player Display Name → Set CurrentDisplayName
       → Print "Welcome, " + CurrentDisplayName
     → False:
       → Print "Login failed: " + Error

5. Create Public Interface

   Function: GetFriendsList
   → Branch: IsLoggedIn?
     → True: Query Friends List → Return Result
     → False: Return Empty Array
   
   Function: UnlockAchievement (Input: AchievementId)
   → Branch: IsLoggedIn?
     → True: Unlock Achievement (AchievementId)
     → False: Print "Must be logged in"

Best Practices

1. Single Manager Instance

   Use a Game Instance subsystem or singleton pattern to ensure only one Online Manager exists.

2. Handle Disconnections

   Bind to OnConnectionStatusChanged to handle network issues:

   On Connection Status Changed (NewStatus)
   → Branch: NewStatus == "Connected"?
     → False: Show "Connection Lost" UI

3. Cache Data

   Friends lists and achievements don’t change frequently. Cache results and refresh periodically:

   // Refresh friends every 60 seconds
   Event BeginPlay
   → Set Timer by Function Name ("RefreshFriends", 60.0, true)

4. Graceful Degradation

   Always have fallback behavior if online features fail:

   Function: SaveGame
   → Try Cloud Save
   → On Failure: Fall back to Local Save

Troubleshooting

Common Issues

Issue	Solution
”Steam not running”	Ensure Steam client is open
”Invalid App ID”	Check steam_appid.txt exists and has correct ID
EOS login fails	Verify all credentials in DefaultEngine.ini
Achievements not appearing	Check they’re published in platform dashboard
Friends list empty	Ensure proper scopes/permissions are configured

Debug Logging

Enable verbose logging:

[Core.Log]
LogOnline=Verbose
LogOnlineSubsystemBlueprintable=Verbose
LogOnlineSession=Verbose

Check logs in Window → Developer Tools → Output Log.

Next Steps

• API Reference - Full node documentation
• FAQ - Common questions
• Discord - Community support