CLI: Add index command / API

code/core/src/cli/bin/index.ts

@@ -10,6 +10,7 @@ import picocolors from 'picocolors';
 import invariant from 'tiny-invariant';
 
 import { build } from '../build';
+import { buildIndex as index } from '../buildIndex';
 import { dev } from '../dev';
 
 addToGlobalContext('cliVersion', versions.storybook);
@@ -127,6 +128,31 @@ command('build')
     }).catch(() => process.exit(1));
   });
 
+command('index')
+  .option('-o, --output-file <file-name>', 'JSON file to output index')
+  .option('-c, --config-dir <dir-name>', 'Directory where to load Storybook configurations from')
+  .option('--quiet', 'Suppress verbose build output')
+  .option('--loglevel <level>', 'Control level of logging during build')
+  .action(async (options) => {
+    process.env.NODE_ENV = process.env.NODE_ENV || 'production';
+    logger.setLevel(options.loglevel);
+    consoleLogger.log(picocolors.bold(`${pkg.name} v${pkg.version}\n`));
+
+    // The key is the field created in `options` variable for
+    // each command line argument. Value is the env variable.
+    getEnvConfig(options, {
+      staticDir: 'SBCONFIG_STATIC_DIR',
+      outputDir: 'SBCONFIG_OUTPUT_DIR',
+      configDir: 'SBCONFIG_CONFIG_DIR',
+    });
+
+    await index({
+      ...options,
+      packageJson: pkg,
+      test: !!options.test || process.env.SB_TESTBUILD === 'true',
+    }).catch(() => process.exit(1));
+  });
+
 program.on('command:*', ([invalidCmd]) => {
   consoleLogger.error(
     ' Invalid command: %s.\n See --help for a list of available commands.',

code/core/src/cli/buildIndex.ts

@@ -0,0 +1,23 @@
+import { cache } from '@storybook/core/common';
+
+import { buildIndexStandalone, withTelemetry } from '@storybook/core/core-server';
+
+import { findPackage } from 'fd-package-json';
+import invariant from 'tiny-invariant';
+
+export const buildIndex = async (cliOptions: any) => {
+  const packageJson = await findPackage(__dirname);
+  invariant(packageJson, 'Failed to find the closest package.json file.');
+  const options = {
+    ...cliOptions,
+    configDir: cliOptions.configDir || './.storybook',
+    outputFile: cliOptions.outputFile || './index.json',
+    ignorePreview: true,
+    configType: 'PRODUCTION',
+    cache,
+    packageJson,
+  };
+  await withTelemetry('index', { cliOptions, presetOptions: options }, () =>
+    buildIndexStandalone(options)
+  );
+};

code/core/src/core-server/build-index.ts

@@ -0,0 +1,71 @@
+import { writeFile } from 'node:fs/promises';
+import { join } from 'node:path';
+import { resolve } from 'node:path';
+
+import { loadAllPresets, loadMainConfig, normalizeStories } from '@storybook/core/common';
+import type { BuilderOptions, CLIOptions, LoadOptions } from '@storybook/core/types';
+
+import { logger } from '@storybook/core/node-logger';
+
+import { StoryIndexGenerator } from './utils/StoryIndexGenerator';
+
+type BuildIndexOptions = CLIOptions & LoadOptions & BuilderOptions & { outputFile: string };
+
+export const buildIndex = async (options: BuildIndexOptions) => {
+  const configDir = resolve(options.configDir ?? '.storybook');
+  const config = await loadMainConfig({
+    configDir,
+    noCache: true,
+  });
+
+  const { framework } = config;
+  const corePresets = [];
+
+  const frameworkName = typeof framework === 'string' ? framework : framework?.name;
+  if (frameworkName) {
+    corePresets.push(join(frameworkName, 'preset'));
+  } else if (!options.ignorePreview) {
+    logger.warn(`you have not specified a framework in your ${options.configDir}/main.js`);
+  }
+
+  const presets = await loadAllPresets({
+    corePresets: [
+      require.resolve('@storybook/core/core-server/presets/common-preset'),
+      ...corePresets,
+    ],
+    overridePresets: [
+      require.resolve('@storybook/core/core-server/presets/common-override-preset'),
+    ],
+    isCritical: true,
+    ...options,
+  });
+  const [indexers, stories, docsOptions] = await Promise.all([
+    // presets.apply('features'),
+    presets.apply('experimental_indexers', []),
+    presets.apply('stories', []),
+    presets.apply('docs', {}),
+  ]);
+
+  const workingDir = process.cwd();
+  const directories = {
+    configDir,
+    workingDir,
+  };
+  const normalizedStories = normalizeStories(stories, directories);
+  const generator = new StoryIndexGenerator(normalizedStories, {
+    ...directories,
+    indexers,
+    docs: docsOptions,
+    build: {},
+  });
+
+  await generator.initialize();
+  const index = await generator.getIndex();
+  return index;
+};
+
+export const buildIndexStandalone = async (options: BuildIndexOptions) => {
+  const index = await buildIndex(options);
+  console.log(`Writing index to ${options.outputFile}`);
+  await writeFile(options.outputFile, JSON.stringify(index, null, 2));
+};

code/core/src/core-server/build-static.ts

@@ -1,5 +1,4 @@
-import { existsSync } from 'node:fs';
-import { cp, mkdir, readdir } from 'node:fs/promises';
+import { cp, mkdir } from 'node:fs/promises';
 import { rm } from 'node:fs/promises';
 import { dirname, join, relative, resolve } from 'node:path';
 

code/core/src/core-server/index.ts

@@ -4,6 +4,7 @@ export { getPreviewHeadTemplate, getPreviewBodyTemplate } from '@storybook/core/
 
 export * from './build-static';
 export * from './build-dev';
+export * from './build-index';
 export * from './withTelemetry';
 export { default as build } from './standalone';
 export { mapStaticDir } from './utils/server-statics';

code/core/src/telemetry/types.ts

@@ -8,6 +8,7 @@ export type EventType =
   | 'boot'
   | 'dev'
   | 'build'
+  | 'index'
   | 'upgrade'
   | 'init'
   | 'scaffolded-empty'

code/lib/cli/src/proxy.ts

@@ -4,7 +4,7 @@ import { spawn } from 'child_process';
 
 const args = process.argv.slice(2);
 
-if (['dev', 'build'].includes(args[0])) {
+if (['dev', 'build', 'index'].includes(args[0])) {
   require('@storybook/core/cli/bin');
 } else {
   const proxiedArgs =