build: compile entry-points in parallel (#7094)

tools/package-tools/build-package.ts

@@ -1,10 +1,11 @@
-import {main as ngc} from '@angular/tsc-wrapped';
+import {red} from 'chalk';
+import {spawn} from 'child_process';
 import {readFileSync, writeFileSync} from 'fs';
 import {sync as glob} from 'glob';
 import {join} from 'path';
+import {PackageBundler} from './build-bundles';
 import {buildConfig} from './build-config';
 import {getSecondaryEntryPointsForPackage} from './secondary-entry-points';
-import {PackageBundler} from './build-bundles';
 
 
 const {packagesDir, outputDir} = buildConfig;
@@ -37,19 +38,23 @@ export class BuildPackage {
   /** Path to the tsconfig file, which will be used to build the tests. */
   private readonly tsconfigTests: string;
 
+  private _secondaryEntryPoints: string[];
+  private _secondaryEntryPointsByDepth: string[][];
+
+  /** Secondary entry-points partitioned by their build depth. */
+  private get secondaryEntryPointsByDepth(): string[][] {
+    this.cacheSecondaryEntryPoints();
+    return this._secondaryEntryPointsByDepth;
+  }
+
   private readonly bundler = new PackageBundler(this);
 
   /** Secondary entry points for the package. */
   get secondaryEntryPoints(): string[] {
-    if (!this._secondaryEntryPoints) {
-      this._secondaryEntryPoints = getSecondaryEntryPointsForPackage(this);
-    }
-
+    this.cacheSecondaryEntryPoints();
     return this._secondaryEntryPoints;
   }
 
-  private _secondaryEntryPoints: string[];
-
   constructor(public readonly name: string, public readonly dependencies: BuildPackage[] = []) {
     this.sourceDir = join(packagesDir, name);
     this.outputDir = join(outputDir, 'packages', name);
@@ -62,9 +67,13 @@ export class BuildPackage {
 
   /** Compiles the package sources with all secondary entry points. */
   async compile() {
-    // Walk through every secondary entry point and build the TypeScript sources sequentially.
-    for (const entryPoint of this.secondaryEntryPoints) {
-      await this._compileEntryPoint(buildTsconfigName, entryPoint);
+    // Compile all secondary entry-points with the same depth in parallel, and each separate depth
+    // group in sequence. This will look something like:
+    // Depth 0: coercion, platform, keycodes, bidi
+    // Depth 1: a11y, scrolling
+    // Depth 2: overlay
+    for (const entryPointGroup of this.secondaryEntryPointsByDepth) {
+      await Promise.all(entryPointGroup.map(p => this._compileEntryPoint(buildTsconfigName, p)));
     }
 
     // Compile the primary entry-point.
@@ -86,8 +95,17 @@ export class BuildPackage {
     const entryPointPath = join(this.sourceDir, secondaryEntryPoint);
     const entryPointTsconfigPath = join(entryPointPath, tsconfigName);
 
-    await ngc(entryPointTsconfigPath, {basePath: entryPointPath});
-    this.renamePrivateReExportsToBeUnique(secondaryEntryPoint);
+    return new Promise((resolve, reject) => {
+      const childProcess = spawn('./node_modules/.bin/ngc', ['-p', entryPointTsconfigPath]);
+
+      // Pipe stdout and stderr from the child process.
+      childProcess.stdout.on('data', (data: any) => console.log(`${data}`));
+      childProcess.stderr.on('data', (data: any) => console.error(red(`${data}`)));
+
+      childProcess.on('exit', (exitCode: number) => exitCode === 0 ? resolve() : reject());
+    })
+    .catch(() => console.error(red(`Failed to compile ${secondaryEntryPoint}`)))
+    .then(() => this.renamePrivateReExportsToBeUnique(secondaryEntryPoint));
   }
 
   /** Renames `ɵa`-style re-exports generated by Angular to be unique across compilation units. */
@@ -107,4 +125,13 @@ export class BuildPackage {
       });
     }
   }
+
+  /** Stores the secondary entry-points for this package if they haven't been computed already. */
+  private cacheSecondaryEntryPoints() {
+    if (!this._secondaryEntryPoints) {
+      this._secondaryEntryPointsByDepth = getSecondaryEntryPointsForPackage(this);
+      this._secondaryEntryPoints =
+        this._secondaryEntryPointsByDepth.reduce((list, p) => list.concat(p), []);
+    }
+  }
 }

tools/package-tools/secondary-entry-points.ts

@@ -24,7 +24,7 @@ export function getSecondaryEntryPointsForPackage(pkg: BuildPackage) {
       .filter(d => existsSync(join(packageDir, d, 'tsconfig-build.json')));
 
   // Create nodes that comprise the build graph.
-  const buildNodes: BuildNode[] = entryPoints.map(p => ({name: p, deps: []}));
+  const buildNodes: BuildNode[] = entryPoints.map(p => ({name: p, deps: [], depth: 0}));
 
   // Create a lookup for name -> build graph node.
   const nodeLookup = buildNodes.reduce((lookup, node) => {
@@ -54,24 +54,27 @@ export function getSecondaryEntryPointsForPackage(pkg: BuildPackage) {
 
   // Concatenate the build order for each node into one global build order.
   // Duplicates are automatically omitted by getBuildOrder.
-  return buildNodes.reduce((order: string[], node) => {
+  const buildOrder = buildNodes.reduce((order: BuildNode[], node) => {
     return [...order, ...getBuildOrder(node)];
   }, []);
+
+  return partitionNodesByDepth(buildOrder).map(level => level.map(node => node.name));
 }
 
-/** Gets the build order for a given node with DFS. */
-function getBuildOrder(node: BuildNode): string[] {
+/** Gets the build order for node with DFS. As a side-effect, sets the depth on visited nodes. */
+function getBuildOrder(node: BuildNode): BuildNode[] {
   if (node.visited) {
     return [];
   }
 
-  let buildOrder: string[] = [];
+  let buildOrder: BuildNode[] = [];
   for (const dep of node.deps) {
     buildOrder = [...buildOrder, ...getBuildOrder(dep)];
+    node.depth = node.deps.reduce((maxDepth, d) => Math.max(d.depth + 1, maxDepth), -1);
   }
 
   node.visited = true;
-  return [...buildOrder, node.name];
+  return [...buildOrder, node];
 }
 
 /** Gets the names of all subdirectories for a given path. */
@@ -84,9 +87,32 @@ interface BuildNode {
   name: string;
   deps: BuildNode[];
   visited?: boolean;
+  depth: number;
 }
 
 
+/**
+ * Partitions nodes into groups by depth. For example,
+ * [{name: a11y, depth: 1}, {name: bidi, depth: 0}, {name: platform, depth: 0}]
+ * =>
+ * [ [{name: bidi, depth: 0}, {name: platform, depth: 0}], [{name: a11y, depth: 1}] ]
+ */
+function partitionNodesByDepth(nodes: BuildNode[]): BuildNode[][] {
+  const result: BuildNode[][] = [[]];
+  let lastDepth = 0;
+
+  nodes.sort((a, b) => a.depth - b.depth).forEach(node => {
+    if (node.depth === lastDepth) {
+      result[result.length - 1].push(node);
+    } else {
+      result.push([node]);
+      lastDepth = node.depth;
+    }
+  });
+
+  return result;
+}
+
 /** Builds the command that will be executed to find all import statements for a package. */
 function buildPackageImportStatementFindCommand(searchDirectory: string, packageName: string) {
   if (platform() === 'win32') {