Extension System

NOTE

Extension support is available starting from launcher version 1.0.0.

The SJMCL extension system is a frontend extension runtime for extending the launcher interface and functionality. Extensions declare themselves through a manifest, attach themselves to the launcher UI through contribution points, and use host-injected APIs to access available capabilities.

System Model

An extension consists of the following parts:

• manifest: describes the extension identifier, name, version, and entry
• UI contributions: declare different UI contribution points to extend the launcher interface and define extension interaction abilities
• host capabilities: injected by the launcher, including React, ChakraUI, launcher runtime data, and context interfaces

Extension scripts run inside a constrained host environment.

Registration Flow

The flow from import to mount is:

1. The user imports a .sjmclx or .zip package.
2. The launcher extracts the package and reads sjmcl.ext.json.
3. If frontend.entry exists, the launcher loads the corresponding script.
4. The script reads document.currentScript.dataset.extensionToken.
5. The script calls window.registerExtension(factory, token).
6. The host executes factory(api) and reads the returned contributions.
7. The contributions are mounted into the home page, settings page, standalone pages, and other locations.

Mount Points

The launcher allows extensions to provide the following UI contributions:

• home cards
• extension settings page
• custom pages
• standalone custom pages

These entries are declared explicitly by the extension during registration.