Zhin Plugin Lifecycle Guide

Use this skill to help developers scaffold and reason about Zhin plugins, including lifecycle hooks, auto-loading behavior, and hot-reload interactions.

Plugin Scaffold

Start with the minimal plugin entry file that uses usePlugin() so Zhin can create a plugin instance for the file:

import { usePlugin } from '@zhin.js/core'

const plugin = usePlugin()

plugin.onMounted(() => {
  plugin.logger.info(`Plugin ${plugin.name} mounted`)
})

plugin.onDispose(() => {
  plugin.logger.info(`Plugin ${plugin.name} disposed`)
})

Key Concepts

• usePlugin() creates (and registers) the plugin instance based on the current file path.
• Plugin names are derived from the file path (package name or folder name).
• plugin.onMounted runs after contexts are mounted and child plugins start.
• plugin.onDispose runs when the plugin is stopped or reloaded.

Hot Reload Behavior

In development mode (NODE_ENV=development), the core will watch plugin files and trigger reloads when they change.

plugin.onMounted(() => {
  plugin.logger.debug('Plugin ready for HMR')
})

Reload Flow

1. File changes trigger plugin.reload().
2. The plugin is stopped via plugin.stop().
3. Parent re-imports the plugin entry file.
4. mounted lifecycle events fire again.

If the plugin is the root plugin, reload exits the process (exit code 51) so the CLI can restart it.

Adding Child Plugins

Use plugin.import() to load child plugins relative to the current file:

await plugin.import('./sub-plugin/index.ts')

Notes:

• The core prevents double-loading the same resolved path.
• Child plugins are stopped automatically when the parent stops.

Common Diagnostics

• plugin.features returns registered commands, components, crons, and middleware names.
• plugin.info() returns a nested tree of features for the plugin and its children.

Use this to build “health” commands for debugging plugin loads.

Checklist When Authoring Plugins

• Ensure the entry file calls usePlugin() once.
• Use onDispose to clean up timers or external connections.
• Use plugin.import() for dependent plugins.
• Prefer plugin.onMounted for deferred setup once contexts are ready.