docusaurus/website/docs/lifecycle-apis.md

id	title
lifecycle-apis	Lifecycle APIs

:::caution

This section is a work in progress.

:::

Lifecycle APIs are shared by Themes and Plugins.

validateOptions({options, validate})

Return validated and normalized options for the plugin. This method is called before the plugin is initialized.You must return options since the returned options will be passed to plugin during initialization.

options

validateOptions is called with options passed to plugin for validation and normalization.

validate

validateOptions is called with validate function which takes a Joi schema and options as argument, returns validated and normalized options. validate will automatically handle error and validation config.

:::tip

Joi is recommended for validation and normalization of options.

To avoid mixing Joi versions, use const {Joi} = require("@docusaurus/utils-validation")

:::

If you don't use Joi for validation you can throw an Error in case of invalid options and return options in case of success.

module.exports = function (context, options) {
  return {
    name: 'docusaurus-plugin',
    // rest of methods
  };
};

module.exports.validateOptions = ({options, validate}) => {
  const validatedOptions = validate(myValidationSchema, options);
  return validationOptions;
};

You can also use ES modules style exports.

export default function (context, options) {
  return {
    name: 'docusaurus-plugin',
    // rest of methods
  };
}

export function validateOptions({options, validate}) {
  const validatedOptions = validate(myValidationSchema, options);
  return validationOptions;
}

validateThemeConfig({themeConfig, validate})

Return validated and normalized configuration for the theme.

themeConfig

validateThemeConfig is called with themeConfig provided in docusaurus.config.js for validation and normalization.

validate

validateThemeConfig is called with validate function which takes a Joi schema and themeConfig as argument, returns validated and normalized options. validate will automatically handle error and validation config.

:::tip

Joi is recommended for validation and normalization of theme config.

To avoid mixing Joi versions, use const {Joi} = require("@docusaurus/utils-validation")

:::

If you don't use Joi for validation you can throw an Error in case of invalid options.

module.exports = function (context, options) {
  return {
    name: 'docusaurus-plugin',
    // rest of methods
  };
};

module.exports.validateThemeConfig = ({themeConfig, validate}) => {
  const validatedThemeConfig = validate(myValidationSchema, options);
  return validatedThemeConfig;
};

You can also use ES modules style exports.

export default function (context, options) {
  return {
    name: 'docusaurus-plugin',
    // rest of methods
  };
}

export function validateThemeConfig({themeConfig, validate}) {
  const validatedThemeConfig = validate(myValidationSchema, options);
  return validatedThemeConfig;
}

getPathsToWatch()

Specifies the paths to watch for plugins and themes. The paths are watched by the dev server so that the plugin lifecycles are reloaded when contents in the watched paths change. Note that the plugins and themes modules are initially called with context and options from Node, which you may use to find the necessary directory information about the site.

Example:

const path = require('path');
module.exports = function (context, options) {
  return {
    name: 'docusaurus-plugin',
    getPathsToWatch() {
      const contentPath = path.resolve(context.siteDir, options.path);
      return [`${contentPath}/**/*.{ts,tsx}`];
    },
  };
};

async loadContent()

Plugins should use this lifecycle to fetch from data sources (filesystem, remote API, headless CMS, etc) or doing some server processing.

For example, this plugin below return a random integer between 1 to 10 as content;

const path = require('path');
module.exports = function (context, options) {
  return {
    name: 'docusaurus-plugin',
    async loadContent() {
      return 1 + Math.floor(Math.random() * 10);
    },
  };
};

async contentLoaded({content, actions})

Plugins should use the data loaded in loadContent and construct the pages/routes that consume the loaded data (optional).

content

contentLoaded will be called after loadContent is done, the return value of loadContent() will be passed to contentLoaded as content.

actions

actions contain two functions:

• addRoute(config: RouteConfig): void

Create a route to add to the website.

interface RouteConfig {
  path: string;
  component: string;
  modules?: RouteModule;
  routes?: RouteConfig[];
  exact?: boolean;
  priority?: number;
}
interface RouteModule {
  [module: string]: Module | RouteModule | RouteModule[];
}
type Module =
  | {
      path: string;
      __import?: boolean;
      query?: ParsedUrlQueryInput;
    }
  | string;

• createData(name: string, data: any): Promise<string>

A function to help you create static data (generally json or string), that you can provide to your routes as props.

For example, this plugin below create a /friends page which display Your friends are: Yangshun, Sebastien:

import React from 'react';

export default function FriendsComponent({friends}) {
  return <div>Your friends are {friends.join(',')}</div>;
}

export default function friendsPlugin(context, options) {
  return {
    name: 'docusaurus-friends-plugin',
    async contentLoaded({content, actions}) {
      const {createData, addRoute} = actions;
      // Create friends.json
      const friends = ['Yangshun', 'Sebastien'];
      const friendsJsonPath = await createData(
        'friends.json',
        JSON.stringify(friends),
      );

      // Add the '/friends' routes, and ensure it receives the friends props
      addRoute({
        path: '/friends',
        component: '@site/src/components/Friends.js',
        modules: {
          // propName -> JSON file path
          friends: friendsJsonPath,
        },
        exact: true,
      });
    },
  };
}

• setGlobalData(data: any): void

This function permits to create some global plugin data, that can be read from any page, including the pages created by other plugins, and your theme layout.

This data become accessible to your client-side/theme code, through the useGlobalData and usePluginData.

One this data is created, you can access it with the global data hooks APIs.

:::caution

Global data is... global: its size affects the loading time of all pages of your site, so try to keep it small.

Prefer createData and page-specific data whenever possible.

:::

For example, this plugin below create a /friends page which display Your friends are: Yangshun, Sebastien:

import React from 'react';
import {usePluginData} from '@docusaurus/useGlobalData';

export default function FriendsComponent() {
  const {friends} = usePluginData('my-friends-plugin');
  return <div>Your friends are {friends.join(',')}</div>;
}

export default function friendsPlugin(context, options) {
  return {
    name: 'docusaurus-friends-plugin',
    async contentLoaded({content, actions}) {
      const {setGlobalData, addRoute} = actions;
      // Create friends global data
      setGlobalData({friends: ['Yangshun', 'Sebastien']});

      // Add the '/friends' routes
      addRoute({
        path: '/friends',
        component: '@site/src/components/Friends.js',
        exact: true,
      });
    },
  };
}

configureWebpack(config, isServer, utils)

Modifies the internal webpack config. If the return value is a JavaScript object, it will be merged into the final config using webpack-merge. If it is a function, it will be called and receive config as the first argument and an isServer flag as the argument argument.

config

configureWebpack is called with config generated according to client/server build. You may treat this as the base config to be merged with.

isServer

configureWebpack will be called both in server build and in client build. The server build receives true and the client build receives false as isServer.

utils

The initial call to configureWebpack also receives a util object consists of three functions:

• getStyleLoaders(isServer: boolean, cssOptions: {[key: string]: any}): Loader[]
• getCacheLoader(isServer: boolean, cacheOptions?: {}): Loader | null
• getBabelLoader(isServer: boolean, babelOptions?: {}): Loader

You may use them to return your webpack configures conditionally.

For example, this plugin below modify the webpack config to transpile .foo file.

module.exports = function (context, options) {
  return {
    name: 'custom-docusaurus-plugin',
    // highlight-start
    configureWebpack(config, isServer, utils) {
      const {getCacheLoader} = utils;
      return {
        module: {
          rules: [
            {
              test: /\.foo$/,
              use: [getCacheLoader(isServer), 'my-custom-webpack-loader'],
            },
          ],
        },
      };
    },
    // highlight-end
  };
};

Merge strategy

We merge the Webpack configuration parts of plugins into the global Webpack config using webpack-merge.

It is possible to specify the merge strategy. For example, if you want a webpack rule to be prepended instead of appended:

module.exports = function (context, options) {
  return {
    name: 'custom-docusaurus-plugin',
    configureWebpack(config, isServer, utils) {
      return {
        // highlight-start
        mergeStrategy: {'module.rules': 'prepend'},
        module: {rules: [myRuleToPrepend]},
        // highlight-end
      };
    },
  };
};

Read the webpack-merge strategy doc for more details.

configurePostCss(options)

Modifies postcssOptions of postcss-loader during the generation of the client bundle.

Should return the mutated postcssOptions.

By default, postcssOptions looks like this:

const postcssOptions = {
  ident: 'postcss',
  plugins: [require('autoprefixer')],
};

Example:

module.exports = function (context, options) {
  return {
    name: 'docusaurus-plugin',
    // highlight-start
    configurePostCss(postcssOptions) {
      // Appends new PostCSS plugin.
      postcssOptions.plugins.push(require('postcss-import'));
      return postcssOptions;
    },
    // highlight-end
  };
};

postBuild(props)

Called when a (production) build finishes.

type Props = {
  siteDir: string;
  generatedFilesDir: string;
  siteConfig: DocusaurusConfig;
  outDir: string;
  baseUrl: string;
  headTags: string;
  preBodyTags: string;
  postBodyTags: string;
  routesPaths: string[];
  plugins: Plugin<any>[];
};

Example:

module.exports = function (context, options) {
  return {
    name: 'docusaurus-plugin',
    async postBuild({siteConfig = {}, routesPaths = [], outDir}) {
      // Print out to console all the rendered routes.
      routesPaths.map((route) => {
        console.log(route);
      });
    },
  };
};

extendCli(cli)

Register an extra command to enhance the CLI of docusaurus. cli is commander object.

Example:

module.exports = function (context, options) {
  return {
    name: 'docusaurus-plugin',
    extendCli(cli) {
      cli
        .command('roll')
        .description('Roll a random number between 1 and 1000')
        .action(() => {
          console.log(Math.floor(Math.random() * 1000 + 1));
        });
    },
  };
};

injectHtmlTags()

Inject head and/or body HTML tags to Docusaurus generated HTML.

function injectHtmlTags(): {
  headTags?: HtmlTags;
  preBodyTags?: HtmlTags;
  postBodyTags?: HtmlTags;
};

type HtmlTags = string | HtmlTagObject | (string | HtmlTagObject)[];

interface HtmlTagObject {
  /**
   * Attributes of the HTML tag
   * E.g. `{'disabled': true, 'value': 'demo', 'rel': 'preconnect'}`
   */
  attributes?: {
    [attributeName: string]: string | boolean;
  };
  /**
   * The tag name e.g. `div`, `script`, `link`, `meta`
   */
  tagName: string;
  /**
   * The inner HTML
   */
  innerHTML?: string;
}

Example:

module.exports = function (context, options) {
  return {
    name: 'docusaurus-plugin',
    // highlight-start
    injectHtmlTags() {
      return {
        headTags: [
          {
            tagName: 'link',
            attributes: {
              rel: 'preconnect',
              href: 'https://www.github.com',
            },
          },
        ],
        preBodyTags: [
          {
            tagName: 'script',
            attributes: {
              charset: 'utf-8',
              src: '/noflash.js',
            },
          },
        ],
        postBodyTags: [`<div> This is post body </div>`],
      };
    },
    // highlight-end
  };
};

getThemePath()

Returns the path to the directory where the theme components can be found. When your users calls swizzle, getThemePath is called and its returned path is used to find your theme components.

If you use the folder directory above, your getThemePath can be:

const path = require('path');

module.exports = function (context, options) {
  return {
    name: 'name-of-my-theme',
    getThemePath() {
      return path.resolve(__dirname, './theme');
    },
  };
};

getTypeScriptThemePath()

Similar to getThemePath(), it should return the path to the directory where the source code of TypeScript theme components can be found. Theme components under this path will not be resolved by Webpack. Therefore, it is not a replacement of getThemePath(). Instead, this path is purely for swizzling TypeScript theme components.

If you want to support TypeScript component swizzling for your theme, you can make the path returned by getTypeScriptThemePath() be your source directory, and make path returned by getThemePath() be the compiled JavaScript output.

Example:

const path = require('path');

module.exports = function (context, options) {
  return {
    name: 'name-of-my-theme',
    getThemePath() {
      // Where compiled JavaScript output lives
      return path.join(__dirname, '..', 'lib', 'theme');
    },
    getTypeScriptThemePath() {
      // Where TypeScript source code lives
      return path.resolve(__dirname, './theme');
    },
  };
};

getSwizzleComponentList()

Return a list of stable component that are considered as safe for swizzling. These components will be listed in swizzle component without --danger. All the components are considers unstable by default. If an empty array is returned then all components are considered unstable, if undefined is returned then all component are considered stable.

const swizzleAllowedComponents = [
  'CodeBlock',
  'DocSidebar',
  'Footer',
  'NotFound',
  'SearchBar',
  'hooks/useTheme',
  'prism-include-languages',
];

module.exports.getSwizzleComponentList = () => swizzleAllowedComponents;

getClientModules()

Returns an array of paths to the modules that are to be imported in the client bundle. These modules are imported globally before React even renders the initial UI.

As an example, to make your theme load a customCss or customJs file path from options passed in by the user:

const path = require('path');

module.exports = function (context, options) {
  const {customCss, customJs} = options || {};
  return {
    name: 'name-of-my-theme',
    getClientModules() {
      return [customCss, customJs];
    },
  };
};

i18n lifecycles

getTranslationFiles({content})

Plugins declare the JSON translation files they want to use.

Returns translation files {path: string, content: ChromeI18nJSON}:

• Path: relative to the plugin localized folder i18n/<locale>/pluginName. Extension .json is not necessary.
• Content: using the Chrome i18n JSON format

These files will be written by the write-translations CLI to the plugin i18n subfolder, and will be read in the appropriate locale before calling translateContent() and translateThemeConfig()

Example:

module.exports = function (context, options) {
  return {
    name: 'my-plugin',
    // highlight-start
    async getTranslationFiles({content}) {
      return [
        {
          path: 'sidebar-labels',
          content: {
            someSidebarLabel: {
              message: 'Some Sidebar Label',
              description: 'A label used in my plugin in the sidebar',
            },
            someLabelFromContent: content.myLabel,
          },
        },
      ];
    },
    // highlight-end
  };
};

translateContent({content,translationFiles})

Translate the plugin content, using the localized translation files.

Returns the localized plugin content.

The contentLoaded() lifecycle will be called with the localized plugin content returned by translateContent().

Example:

module.exports = function (context, options) {
  return {
    name: 'my-plugin',
    // highlight-start
    translateContent({content, translationFiles}) {
      const myTranslationFile = translationFiles.find(
        (f) => f.path === 'myTranslationFile',
      );
      return {
        ...content,
        someContentLabel: myTranslationFile.someContentLabel.message,
      };
    },
    // highlight-end
  };
};

translateThemeConfig({themeConfig,translationFiles})

Translate the site themeConfig labels, using the localized translation files.

Returns the localized themeConfig.

Example:

module.exports = function (context, options) {
  return {
    name: 'my-theme',
    // highlight-start
    translateThemeConfig({themeConfig, translationFiles}) {
      const myTranslationFile = translationFiles.find(
        (f) => f.path === 'myTranslationFile',
      );
      return {
        ...themeConfig,
        someThemeConfigLabel: myTranslationFile.someThemeConfigLabel.message,
      };
    },
    // highlight-end
  };
};

async getDefaultCodeTranslationMessages()

Themes using the <Translate> API can provide default code translation messages.

It should return messages in Record<string,string>, where keys are translation ids and values are messages (without the description) localized using the site current locale.

Example:

module.exports = function (context, options) {
  return {
    name: 'my-theme',
    // highlight-start
    async getDefaultCodeTranslationMessages() {
      return readJsonFile(`${context.i18n.currentLocale}.json`);
    },
    // highlight-end
  };
};

Example

Here's a mind model for a presumptuous plugin implementation.

const DEFAULT_OPTIONS = {
  // Some defaults.
};

// A JavaScript function that returns an object.
// `context` is provided by Docusaurus. Example: siteConfig can be accessed from context.
// `opts` is the user-defined options.
module.exports = function (context, opts) {
  // Merge defaults with user-defined options.
  const options = {...DEFAULT_OPTIONS, ...options};

  return {
    // A compulsory field used as the namespace for directories to cache
    // the intermediate data for each plugin.
    // If you're writing your own local plugin, you will want it to
    // be unique in order not to potentially conflict with imported plugins.
    // A good way will be to add your own project name within.
    name: 'docusaurus-my-project-cool-plugin',

    async loadContent() {
      // The loadContent hook is executed after siteConfig and env has been loaded.
      // You can return a JavaScript object that will be passed to contentLoaded hook.
    },

    async contentLoaded({content, actions}) {
      // The contentLoaded hook is done after loadContent hook is done.
      // `actions` are set of functional API provided by Docusaurus (e.g. addRoute)
    },

    async postBuild(props) {
      // After docusaurus <build> finish.
    },

    // TODO
    async postStart(props) {
      // docusaurus <start> finish
    },

    // TODO
    afterDevServer(app, server) {
      // https://webpack.js.org/configuration/dev-server/#devserverbefore
    },

    // TODO
    beforeDevServer(app, server) {
      // https://webpack.js.org/configuration/dev-server/#devserverafter
    },

    configureWebpack(config, isServer) {
      // Modify internal webpack config. If returned value is an Object, it
      // will be merged into the final config using webpack-merge;
      // If the returned value is a function, it will receive the config as the 1st argument and an isServer flag as the 2nd argument.
    },

    getPathsToWatch() {
      // Paths to watch.
    },

    getThemePath() {
      // Returns the path to the directory where the theme components can
      // be found.
    },

    getClientModules() {
      // Return an array of paths to the modules that are to be imported
      // in the client bundle. These modules are imported globally before
      // React even renders the initial UI.
    },

    extendCli(cli) {
      // Register an extra command to enhance the CLI of Docusaurus
    },

    injectHtmlTags() {
      // Inject head and/or body HTML tags.
    },

    async getTranslationFiles() {
      // Return translation files
    },

    translateContent({content, translationFiles}) {
      // translate the plugin content here
    },

    translateThemeConfig({themeConfig, translationFiles}) {
      // translate the site themeConfig here
    },

    async getDefaultCodeTranslationMessages() {
      // return default theme translations here
    },
  };
};