Fix #1613

packages/@vuepress/core/lib/node/App.js

@@ -105,6 +105,9 @@ module.exports = class App {
     this.applyUserPlugins()
     this.pluginAPI.initialize()
 
+    // invoke init hook
+    await this.pluginAPI.applyAsyncOption('init')
+
     this.markdown = createMarkdown(this)
 
     await this.resolvePages()

packages/@vuepress/core/lib/node/__tests__/plugin-api/PluginAPI.spec.js

@@ -9,7 +9,11 @@ describe('Plugin', () => {
   test('registerOption', () => {
     const api = new PluginAPI()
     const readyHandler = () => {}
+    const initHandler = () => {}
+    api.registerOption(PLUGIN_OPTION_MAP.INIT.key, initHandler)
     api.registerOption(PLUGIN_OPTION_MAP.READY.key, readyHandler)
+    expect(api.options.init.values).toHaveLength(1)
+    expect(api.options.init.values[0]).toBe(initHandler)
     expect(api.options.ready.values).toHaveLength(1)
     expect(api.options.ready.values[0]).toBe(readyHandler)
   })

packages/@vuepress/core/lib/node/plugin-api/constants.js

@@ -2,6 +2,7 @@
 
 const PLUGIN_OPTION_META_MAP = {
   // hooks
+  INIT: { name: 'init', types: [Function], async: true },
   READY: { name: 'ready', types: [Function], async: true },
   COMPILED: { name: 'compiled', types: [Function] },
   UPDATED: { name: 'updated', types: [Function] },

packages/@vuepress/core/lib/node/plugin-api/index.js

@@ -193,6 +193,7 @@ module.exports = class PluginAPI {
     shortcut,
 
     // hooks
+    init,
     ready,
     compiled,
     updated,
@@ -222,6 +223,7 @@ module.exports = class PluginAPI {
     }
 
     this
+      .registerOption(PLUGIN_OPTION_MAP.INIT.key, init, pluginName)
       .registerOption(PLUGIN_OPTION_MAP.READY.key, ready, pluginName)
       .registerOption(PLUGIN_OPTION_MAP.COMPILED.key, compiled, pluginName)
       .registerOption(PLUGIN_OPTION_MAP.UPDATED.key, updated, pluginName)

packages/docs/docs/plugin/life-cycle.md

@@ -1,5 +1,22 @@
 # Lifecycle
 
+## init
+
+- Type: `AsyncFunction`
+- Scope：`dev|build`
+
+```js
+module.exports = {
+  async init() {
+    // ...
+  }
+}
+```
+
+::: tip
+The `init` hook is executed before the build process.
+:::
+
 ## ready
 
 - Type: `AsyncFunction`