feat: init plugin

docs/.vuepress/config.js

@@ -25,6 +25,11 @@ module.exports = {
   ],
   serviceWorker: true,
   theme: 'vue',
+  plugins: [
+    [
+      require('../../lib/plugins/vuepress-plugin-last-updated/index'),
+    ]
+  ],
   themeConfig: {
     repo: 'vuejs/vuepress',
     editLinks: true,

lib/plugin-api/hook.js

+module.exports = class Hook {
+  constructor (name) {
+    this.name = name
+    this.handlers = []
+  }
+
+  tap (symbol, handler) {
+    if (typeof handler !== 'function') {
+      return
+    }
+    this.handlers.push({ symbol, handler })
+    return this
+  }
+
+  remove (symbol) {
+    const index = this.handlers.findIndex(item => item.symbol === symbol)
+    if (index !== -1) {
+      this.handlers.splice(index, 1)
+    }
+    return this
+  }
+
+  async run () {
+    for (const item of this.handlers) {
+      await item.handler.apply(null, arguments)
+    }
+  }
+}

lib/plugin-api/index.js

+const { resolvePlugin, inferPluginName } = require('./util')
+const Hook = require('./hook')
+
+module.exports = class Plugin {
+  constructor (pluginConfigs) {
+    this.hooks = {}
+    this.apis = {}
+    this.extendHooks([
+      'ready',
+      'compiled',
+      'updated',
+      'generated'
+    ])
+    this.extendAPIs([
+      'client',
+      'chainWebpack',
+      'enhanceDevServer',
+      'extendMarkdown',
+      'enhanceAppFiles',
+      'outFiles',
+      'extendPageData'
+    ])
+    this.resolvePluginConfig(pluginConfigs)
+  }
+
+  extendHooks (hooks) {
+    hooks.forEach(hook => {
+      this.hooks[hook] = new Hook(hook)
+    })
+  }
+
+  extendAPIs (apis) {
+    apis.forEach(api => {
+      this.apis[api] = []
+    })
+  }
+
+  resolvePluginConfigs (pluginConfigs) {
+    pluginConfigs.forEach(([name, pluginOptions]) => {
+      let plugin = resolvePlugin(name)
+      if (typeof plugin === 'function') {
+        plugin = plugin(pluginOptions)
+      }
+      plugin = Object.assign(plugin, { name: inferPluginName(name, plugin) })
+      this.resolvePluginConfig(plugin)
+    })
+  }
+
+  registerHook (name, hook, symbol) {
+    this.hooks[name].tap(symbol, hook)
+    return this
+  }
+
+  registerAPI (name, api) {
+    this.apis[name].push(api)
+    return this
+  }
+
+  resolvePluginConfig ({
+    name,
+    client,
+    chainWebpack,
+    enhanceDevServer,
+    extendMarkdown,
+    enhanceAppFiles,
+    outFiles,
+    extendPageData,
+    ready,
+    compiled,
+    updated,
+    generated
+  }) {
+    console.log(this.hooks)
+    this
+      .registerHook('ready', ready, name)
+      .registerHook('compiled', compiled, name)
+      .registerHook('updated', updated, name)
+      .registerHook('generated', generated, name)
+
+    this
+      .registerAPI('client', client)
+      .registerAPI('chainWebpack', chainWebpack)
+      .registerAPI('enhanceDevServer', enhanceDevServer)
+      .registerAPI('extendMarkdown', extendMarkdown)
+      .registerAPI('enhanceAppFiles', enhanceAppFiles)
+      .registerAPI('outFiles', outFiles)
+      .registerAPI('extendPageData', extendPageData)
+  }
+}

lib/plugin-api/util.js

+const logger = require('../util/logger')
+const chalk = require('chalk')
+
+exports.resolvePlugin = function (pluginName) {
+  if (typeof pluginName === 'function' || typeof pluginName === 'object') {
+    return pluginName
+  }
+  if (typeof pluginName === 'string') {
+    try {
+      return require(pluginName.startsWith('vuepress-plugin-')
+        ? pluginName
+        : `vuepress-plugin-${pluginName}`
+      )
+    } catch (err) {
+      console.error(chalk.red(logger.error(`\n[vuepress] Cannot resolve plugin: ${pluginName}\n`, false)))
+      throw new Error(err)
+    }
+  }
+  logger.warn(`\n[vuepress] Invalid plugin usage: ${chalk.yellow(pluginName)}\n`)
+}
+
+exports.inferPluginName = function (pluginName, pluginConfig) {
+  if (pluginConfig.name) {
+    return pluginConfig.name
+  }
+  if (typeof pluginName === 'string') {
+    if (pluginName.startsWith('vuepress-plugin-')) {
+      return pluginName.slice(16)
+    }
+    return pluginName
+  }
+  // ensure each plugin have a unique name.
+  return Date.now().toString(16)
+}

lib/plugins/vuepress-plugin-last-updated/index.js

+const path = require('path')
+const spawn = require('cross-spawn')
+
+module.exports = options => ({
+  client: path.resolve(__dirname, 'client.js'),
+  extendPageData (filepath) {
+    return {
+      lastModified: getGitLastUpdatedTimeStamp(filepath)
+    }
+  }
+})
+
+function getGitLastUpdatedTimeStamp (filepath) {
+  return parseInt(spawn.sync('git', ['log', '-1', '--format=%ct', filepath]).stdout.toString('utf-8')) * 1000
+}

lib/prepare/resolveOptions.js

@@ -2,6 +2,7 @@ const fs = require('fs-extra')
 const path = require('path')
 const globby = require('globby')
 const createMarkdown = require('../markdown')
+const Plugin = require('../plugin-api')
 const loadConfig = require('./loadConfig')
 const { encodePath, fileToPath, sort, getGitLastUpdatedTimeStamp } = require('./util')
 const {
@@ -32,6 +33,14 @@ module.exports = async function resolveOptions (sourceDir) {
     })
   }
 
+  // resolve plugins
+  const plugins = (Array.isArray(siteConfig.plugins)
+    ? siteConfig.plugins
+    : []
+  )
+  const plugin = new Plugin(plugins)
+  console.log(plugin)
+
   // resolve outDir
   const outDir = siteConfig.dest
     ? path.resolve(siteConfig.dest)
@@ -99,7 +108,7 @@ module.exports = async function resolveOptions (sourceDir) {
   const isAlgoliaSearch = (
     themeConfig.algolia ||
     Object.keys(siteConfig.locales && themeConfig.locales || {})
-          .some(base => themeConfig.locales[base].algolia)
+      .some(base => themeConfig.locales[base].algolia)
   )
 
   // resolve markdown
@@ -112,7 +121,7 @@ module.exports = async function resolveOptions (sourceDir) {
   const shouldResolveLastUpdated = (
     themeConfig.lastUpdated ||
     Object.keys(siteConfig.locales && themeConfig.locales || {})
-          .some(base => themeConfig.locales[base].lastUpdated)
+      .some(base => themeConfig.locales[base].lastUpdated)
   )
 
   // resolve pagesData
@@ -124,6 +133,13 @@ module.exports = async function resolveOptions (sourceDir) {
       path: encodePath(fileToPath(file))
     }
 
+    for (const fn of plugin.apis.extendPageData) {
+      const res = await fn(file)
+      if (typeof res === 'object') {
+        Object.assign(data, res)
+      }
+    }
+
     if (shouldResolveLastUpdated) {
       data.lastUpdated = getGitLastUpdatedTimeStamp(filepath)
     }
@@ -178,7 +194,8 @@ module.exports = async function resolveOptions (sourceDir) {
     themeEnhanceAppPath,
     useDefaultTheme,
     isAlgoliaSearch,
-    markdown
+    markdown,
+    plugin
   }
 
   return options