Custom Storage

By default Server Core stores data as JSON files. To keep data in a database, a REST API or anything else, for example to share bans between several servers, write your own storage class.

1. Subclass UServerCoreStorage

MyServerCoreStorage.h

#pragma once

#include "ServerCoreStorage.h"
#include "MyServerCoreStorage.generated.h"

UCLASS()
class UMyServerCoreStorage : public UServerCoreStorage
{
    GENERATED_BODY()

public:
    virtual bool LoadDatabase(FServerCoreDatabase& OutDatabase) override;
    virtual bool SaveDatabase(const FServerCoreDatabase& Database, EServerCoreDataCategory Categories) override;
    virtual void AppendLogEntry(const FServerCoreLogEntry& Entry) override;
    virtual void LoadRecentLogEntries(int32 MaxEntries, TArray<FServerCoreLogEntry>& OutEntries) override;
};

Function	Called	Notes
InitializeStorage(DataDirectory)	Once, before loading	Optional override. Open connections here.
LoadDatabase	On start and on /reload	Fill only what you have, leave other fields untouched
SaveDatabase	Shortly after every change, and on shutdown	Categories tells you what changed (Bans, Mutes, Whitelist, Groups, Players, Notes)
AppendLogEntry	For every admin log entry	Optional
LoadRecentLogEntries	On start	Optional, oldest first

warning

LoadDatabase and SaveDatabase are called on the game thread. If your backend is slow, keep a local cache and sync in the background, or saves will cause hitches.

2. Select it

Project Settings → Plugins → Server Core → Storage Class → MyServerCoreStorage.

Sharing bans between servers

A simple pattern is to store bans, mutes, groups and the whitelist in a shared database, and keep players and notes local. Call Reload Data (or the /reload command) on your servers after another server changes data, or poll on a timer.

Extending the JSON storage

You can also subclass UServerCoreJsonStorage and only override parts of it, for example AppendLogEntry to also send logs to a web service.