feat(v2): Collect plugin versions to allow them to be inspected in debug plugin

[SamChou19815]

Motivation

Implements the proposal in #3042.

@docusaurus/core will collect and generate all the plugin version at start time, and put them into .docusaurus/site-metadata.json. To find the version of the plugin, I choose to walked up the directory of the resolved path until it hits a directory with package.json.

The version information has 4 possible categories:

• package: plugin is external to the current docusaurus project, with will be attached with a version string if it can be found in package.json
• project: plugin is inside the same docusaurus project
• local: some random place on the filesystem that doesn't have any package.json in its ancestor directories.
• synthetic: only used to workaround the synthetic docusaurus-bootstrap-plugin:

  docusaurus/packages/docusaurus/src/server/index.ts

  Lines 97 to 131 in 6e43c9b

  	plugins.push({
  	name: 'docusaurus-bootstrap-plugin',
  	configureWebpack: () => ({
  	resolve: {
  	alias,
  	},
  	}),
  	injectHtmlTags: () => {
  	const stylesheetsTags = stylesheets.map((source) =>
  	typeof source === 'string'
  	? `<link rel="stylesheet" href="${source}">`
  	: {
  	tagName: 'link',
  	attributes: {
  	rel: 'stylesheet',
  	...source,
  	},
  	},
  	);
  	const scriptsTags = scripts.map((source) =>
  	typeof source === 'string'
  	? `<script type="text/javascript" src="${source}"></script>`
  	: {
  	tagName: 'script',
  	attributes: {
  	type: 'text/javascript',
  	...source,
  	},
  	},
  	);
  	return {
  	headTags: [...stylesheetsTags, ...scriptsTags],
  	};
  	},
  	});

Have you read the Contributing Guidelines on pull requests?

Yes

Test Plan

• Added unit test to test the version resolution behavior.
• works on debug page:

• generated site-metadata.json for v2 website:

{
  "docusaurusVersion": "2.0.0-alpha.58",
  "siteVersion": "2.0.0-alpha.58",
  "pluginVersions": {
    "docusaurus-plugin-content-docs": {
      "type": "package",
      "version": "2.0.0-alpha.58"
    },
    "docusaurus-plugin-content-blog": {
      "type": "package",
      "version": "2.0.0-alpha.58"
    },
    "docusaurus-plugin-content-pages": {
      "type": "package",
      "version": "2.0.0-alpha.58"
    },
    "docusaurus-plugin-debug": {
      "type": "package",
      "version": "2.0.0-alpha.58"
    },
    "docusaurus-theme-classic": {
      "type": "package",
      "version": "2.0.0-alpha.58"
    },
    "docusaurus-theme-search-algolia": {
      "type": "package",
      "version": "2.0.0-alpha.58"
    },
    "docusaurus-plugin-client-redirects": {
      "type": "package",
      "version": "2.0.0-alpha.58"
    },
    "docusaurus-plugin-ideal-image": {
      "type": "package",
      "version": "2.0.0-alpha.58"
    },
    "docusaurus-plugin-pwa": {
      "type": "package",
      "version": "2.0.0-alpha.58"
    },
    "docusaurus-theme-live-codeblock": {
      "type": "package",
      "version": "2.0.0-alpha.58"
    }
  }
}

Related PRs

(If this PR adds or changes functionality, please take some time to update the docs at https://github.com/facebook/docusaurus, and link to your PR here.)

[docusaurus-bot]

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[slorber]

Awesome, seems to work fine!