feat(@angular-devkit/build-angular): add Browser Builder v2

It exposes a lot of functions that can be reused to run webpack with
different config, so third party builders can reuse those.

packages/angular_devkit/build_angular/builders.json

@@ -7,6 +7,7 @@
       "description": "Build a server app and a browser app, then render the index.html and use it for the browser output."
     },
     "browser": {
+      "implementation": "./src/browser/index2",
       "class": "./src/browser",
       "schema": "./src/browser/schema.json",
       "description": "Build a browser app."

packages/angular_devkit/build_angular/src/browser/index2.ts

@@ -0,0 +1,298 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+import { BuilderContext, BuilderOutput, createBuilder } from '@angular-devkit/architect/src/index2';
+import {
+  WebpackLoggingCallback,
+  runWebpack,
+} from '@angular-devkit/build-webpack/src/webpack/index2';
+import {
+  Path,
+  experimental,
+  getSystemPath,
+  join,
+  json,
+  logging,
+  normalize,
+  resolve,
+  schema,
+  virtualFs,
+} from '@angular-devkit/core';
+import { NodeJsSyncHost } from '@angular-devkit/core/node';
+import * as fs from 'fs';
+import { EMPTY, Observable, from, of } from 'rxjs';
+import { concatMap, last, map, switchMap } from 'rxjs/operators';
+import * as ts from 'typescript'; // tslint:disable-line:no-implicit-dependencies
+import { WebpackConfigOptions } from '../angular-cli-files/models/build-options';
+import {
+  getAotConfig,
+  getBrowserConfig,
+  getCommonConfig,
+  getNonAotConfig,
+  getStatsConfig,
+  getStylesConfig,
+} from '../angular-cli-files/models/webpack-configs';
+import { readTsconfig } from '../angular-cli-files/utilities/read-tsconfig';
+import { requireProjectModule } from '../angular-cli-files/utilities/require-project-module';
+import { augmentAppWithServiceWorker } from '../angular-cli-files/utilities/service-worker';
+import {
+  statsErrorsToString,
+  statsToString,
+  statsWarningsToString,
+} from '../angular-cli-files/utilities/stats';
+import { NormalizedBrowserBuilderSchema, defaultProgress, normalizeBrowserSchema } from '../utils';
+import { Schema as BrowserBuilderSchema } from './schema';
+
+import webpack = require('webpack');
+const SpeedMeasurePlugin = require('speed-measure-webpack-plugin');
+const webpackMerge = require('webpack-merge');
+
+
+export type BrowserBuilderOutput = json.JsonObject & BuilderOutput & {
+  outputPath: string;
+};
+
+
+function _deleteOutputDir(root: Path, outputPath: Path, host: virtualFs.Host) {
+  const resolvedOutputPath = resolve(root, outputPath);
+  if (resolvedOutputPath === root) {
+    throw new Error('Output path MUST not be project root directory!');
+  }
+
+  return host.exists(resolvedOutputPath).pipe(
+    concatMap(exists => exists ? host.delete(resolvedOutputPath) : EMPTY),
+    last(null, null),
+  );
+}
+
+
+export function createBrowserLoggingCallback(
+  verbose: boolean,
+  logger: logging.LoggerApi,
+): WebpackLoggingCallback {
+  return (stats, config) => {
+    // config.stats contains our own stats settings, added during buildWebpackConfig().
+    const json = stats.toJson(config.stats);
+    if (verbose) {
+      logger.info(stats.toString(config.stats));
+    } else {
+      logger.info(statsToString(json, config.stats));
+    }
+
+    if (stats.hasWarnings()) {
+      logger.warn(statsWarningsToString(json, config.stats));
+    }
+    if (stats.hasErrors()) {
+      logger.error(statsErrorsToString(json, config.stats));
+    }
+  };
+}
+
+export function buildWebpackConfig(
+  root: Path,
+  projectRoot: Path,
+  host: virtualFs.Host<fs.Stats>,
+  options: NormalizedBrowserBuilderSchema,
+  logger: logging.LoggerApi,
+): webpack.Configuration {
+  // Ensure Build Optimizer is only used with AOT.
+  if (options.buildOptimizer && !options.aot) {
+    throw new Error(`The 'buildOptimizer' option cannot be used without 'aot'.`);
+  }
+
+  let wco: WebpackConfigOptions<NormalizedBrowserBuilderSchema>;
+
+  const tsConfigPath = getSystemPath(normalize(resolve(root, normalize(options.tsConfig))));
+  const tsConfig = readTsconfig(tsConfigPath);
+
+  const projectTs = requireProjectModule(getSystemPath(projectRoot), 'typescript') as typeof ts;
+
+  const supportES2015 = tsConfig.options.target !== projectTs.ScriptTarget.ES3
+    && tsConfig.options.target !== projectTs.ScriptTarget.ES5;
+
+  wco = {
+    root: getSystemPath(root),
+    logger: logger.createChild('webpackConfigOptions'),
+    projectRoot: getSystemPath(projectRoot),
+    buildOptions: options,
+    tsConfig,
+    tsConfigPath,
+    supportES2015,
+  };
+
+  wco.buildOptions.progress = defaultProgress(wco.buildOptions.progress);
+
+  const webpackConfigs: {}[] = [
+    getCommonConfig(wco),
+    getBrowserConfig(wco),
+    getStylesConfig(wco),
+    getStatsConfig(wco),
+  ];
+
+  if (wco.buildOptions.main || wco.buildOptions.polyfills) {
+    const typescriptConfigPartial = wco.buildOptions.aot
+      ? getAotConfig(wco, host)
+      : getNonAotConfig(wco, host);
+    webpackConfigs.push(typescriptConfigPartial);
+  }
+
+  const webpackConfig = webpackMerge(webpackConfigs);
+
+  if (options.profile) {
+    const smp = new SpeedMeasurePlugin({
+      outputFormat: 'json',
+      outputTarget: getSystemPath(join(root, 'speed-measure-plugin.json')),
+    });
+
+    return smp.wrap(webpackConfig);
+  }
+
+  return webpackConfig;
+}
+
+
+export async function buildBrowserWebpackConfigFromWorkspace(
+  options: BrowserBuilderSchema,
+  projectName: string,
+  workspace: experimental.workspace.Workspace,
+  host: virtualFs.Host<fs.Stats>,
+  logger: logging.LoggerApi,
+): Promise<webpack.Configuration> {
+  // TODO: Use a better interface for workspace access.
+  const projectRoot = resolve(workspace.root, normalize(workspace.getProject(projectName).root));
+  const sourceRoot = workspace.getProject(projectName).sourceRoot;
+
+  const normalizedOptions = normalizeBrowserSchema(
+    host,
+    workspace.root,
+    projectRoot,
+    sourceRoot ? resolve(workspace.root, normalize(sourceRoot)) : undefined,
+    options,
+  );
+
+  return buildWebpackConfig(workspace.root, projectRoot, host, normalizedOptions, logger);
+}
+
+
+export async function buildBrowserWebpackConfigFromContext(
+  options: BrowserBuilderSchema,
+  context: BuilderContext,
+  host: virtualFs.Host<fs.Stats>,
+): Promise<{ workspace: experimental.workspace.Workspace, config: webpack.Configuration }> {
+  const registry = new schema.CoreSchemaRegistry();
+  registry.addPostTransform(schema.transforms.addUndefinedDefaults);
+
+  const workspace = await experimental.workspace.Workspace.fromPath(
+    host,
+    normalize(context.workspaceRoot),
+    registry,
+  );
+
+  const projectName = context.target ? context.target.project : workspace.getDefaultProjectName();
+
+  if (!projectName) {
+    throw new Error('Must either have a target from the context or a default project.');
+  }
+
+  const config = await buildBrowserWebpackConfigFromWorkspace(
+    options,
+    projectName,
+    workspace,
+    host,
+    context.logger,
+  );
+
+  return { workspace, config };
+}
+
+
+export type BrowserConfigTransformFn = (
+  workspace: experimental.workspace.Workspace,
+  config: webpack.Configuration,
+) => Observable<webpack.Configuration>;
+
+export function buildWebpackBrowser(
+  options: BrowserBuilderSchema,
+  context: BuilderContext,
+  transforms: {
+    config?: BrowserConfigTransformFn,
+    output?: (output: BrowserBuilderOutput) => Observable<BuilderOutput>,
+    logging?: WebpackLoggingCallback,
+  } = {},
+) {
+  const host = new NodeJsSyncHost();
+  const root = normalize(context.workspaceRoot);
+
+  const configFn = transforms.config;
+  const outputFn = transforms.output;
+  const loggingFn = transforms.logging
+      || createBrowserLoggingCallback(!!options.verbose, context.logger);
+
+  // This makes a host observable into a cold one. This is because we want to wait until
+  // subscription before calling buildBrowserWebpackConfigFromContext, which can throw.
+  return of(null).pipe(
+    switchMap(() => from(buildBrowserWebpackConfigFromContext(options, context, host))),
+    switchMap(({ workspace, config }) => {
+      if (configFn) {
+        return configFn(workspace, config).pipe(
+          map(config => ({ workspace, config })),
+        );
+      } else {
+        return of({ workspace, config });
+      }
+    }),
+    switchMap(({workspace, config}) => {
+      if (options.deleteOutputPath) {
+        return _deleteOutputDir(
+          normalize(context.workspaceRoot),
+          normalize(options.outputPath),
+          host,
+        ).pipe(map(() => ({ workspace, config })));
+      } else {
+        return of({ workspace, config });
+      }
+    }),
+    switchMap(({ workspace, config }) => {
+      const projectName = context.target
+        ? context.target.project : workspace.getDefaultProjectName();
+
+      if (!projectName) {
+        throw new Error('Must either have a target from the context or a default project.');
+      }
+
+      const projectRoot = resolve(
+        workspace.root,
+        normalize(workspace.getProject(projectName).root),
+      );
+
+      return runWebpack(config, context, { logging: loggingFn }).pipe(
+        concatMap(buildEvent => {
+          if (buildEvent.success && !options.watch && options.serviceWorker) {
+            return from(augmentAppWithServiceWorker(
+              host,
+              root,
+              projectRoot,
+              resolve(root, normalize(options.outputPath)),
+              options.baseHref || '/',
+              options.ngswConfigPath,
+            ).then(() => ({ success: true })));
+          } else {
+            return of(buildEvent);
+          }
+        }),
+        map(event => ({
+          ...event,
+          outputPath: config.output && config.output.path || '',
+        } as BrowserBuilderOutput)),
+        concatMap(output => outputFn ? outputFn(output) : of(output)),
+      );
+    }),
+  );
+}
+
+
+export default createBuilder<json.JsonObject & BrowserBuilderSchema>(buildWebpackBrowser);