RuntimeLogger

Description

This plugin allows you to store, write, and visualize your runtime-generated logs from various threads and create notifications about them. It is Blueprint-exposed and designed especially for shipping builds and runtime usage.

Workflow

• Log Manager (Blueprint Exposed)
  This is a UGameInstanceSubsystem (Runtime Logger Subsystem).
  It is unaffected by level changes and has a singleton/centralized design, so you can access it from anywhere.

• Log Message (Blueprint Exposed)
  This function uses TQueue to gather your messages from every thread without race conditions.
  Each message is a JSON object. You can define your own structure, but it automatically includes:

  • UUID (FGuid-based)
  • LogTime (FDateTime::Now())
  • LogLevel (ERuntimeLogLevels custom enum)

  We suggest adding:

  • Plugin (or module) name
  • Class name
  • Function name

  If you use C++, you can take advantage of __FUNCSIG__ to automatically add class and function names (compiler feature).

• Record Message
  This is a public C++ function running on FRunnableThread, so it won't affect game thread performance even with many logs. If there are no logs to record, the thread stays in a wait state, avoiding wasted resources.

  Logs are stored in a private TMap<FString, FString> accessible via getters:

  • Key: UUID
  • Value: Other parameters

  It also writes a text file in your project's Saved directory named like:
  ProjectName_RuntimeLogger_Date.log

  The file contains a JSON object array.

  • If you want to use it before the game closes, you must manually append a ] at the end.
  • Upon closing, the function automatically appends it.

  We append entries without reopening the file handle each time for performance reasons.
  A delegate notifies you when a log is generated, and its execution chain runs via AsyncTask(GameThread), allowing safe widget creation.
  You can extend this with features like API calls, email notifications, or database writes.

• Automatic Widget with Search Box and Criticality Filter

Tutorial

Check the plugin's Content folder for sample Blueprints.

Platform Support

No platform-specific code is used, so it should work on any platform.
Tested only on Windows and Android — no official support for others, especially editor-side.

Engine Support

No UE4 or older versions are supported.
Only the latest Unreal Engine version is supported.
Updates will be provided about one month after a new major release.