chore(internal API): introduce an internal API for ngtools. (#13415)

modules/@angular/compiler-cli/src/ngtools_api.ts

@@ -0,0 +1,124 @@
+/**
+ * This is a private API for the ngtools toolkit.
+ *
+ * This API should be stable for NG 2. It can be removed in NG 4..., but should be replaced by
+ * something else.
+ */
+
+import * as ts from 'typescript';
+import {StaticReflector, AotCompilerHost} from '@angular/compiler';
+import {AngularCompilerOptions, NgcCliOptions} from '@angular/tsc-wrapped';
+
+import {CodeGenerator} from './codegen';
+import {CompilerHost, CompilerHostContext, ModuleResolutionHostAdapter} from './compiler_host';
+import {listLazyRoutesOfModule} from './ngtools_impl';
+import {PathMappedCompilerHost} from './path_mapped_compiler_host';
+
+
+export interface NgTools_InternalApi_NG2_CodeGen_Options {
+  basePath: string;
+  compilerOptions: ts.CompilerOptions;
+  program: ts.Program;
+  host: ts.CompilerHost;
+
+  angularCompilerOptions: AngularCompilerOptions;
+
+  // i18n options.
+  i18nFormat: string;
+  i18nFile: string;
+  locale: string;
+
+  readResource: (fileName: string) => Promise<string>;
+
+  // Every new property under this line should be optional.
+}
+
+export interface NgTools_InternalApi_NG2_ListLazyRoutes_Options {
+  program: ts.Program;
+  host: ts.CompilerHost;
+  angularCompilerOptions: AngularCompilerOptions;
+  entryModule: string;
+
+  // Every new property under this line should be optional.
+}
+
+
+export interface NgTools_InternalApi_NG_2_LazyRouteMap {
+  [route: string]: string;
+}
+
+
+/**
+ * A ModuleResolutionHostAdapter that overrides the readResource() method with the one
+ * passed in the interface.
+ */
+class CustomLoaderModuleResolutionHostAdapter extends ModuleResolutionHostAdapter {
+  constructor(private _readResource: (path: string) => Promise<string>,
+              host: ts.ModuleResolutionHost) {
+    super(host);
+  }
+
+  readResource(path: string) {
+    return this._readResource(path);
+  }
+}
+
+
+/**
+ * @internal
+ * @private
+ */
+export class NgTools_InternalApi_NG_2 {
+  /**
+   * @internal
+   * @private
+   */
+  static codeGen(options: NgTools_InternalApi_NG2_CodeGen_Options): Promise<void> {
+    const hostContext: CompilerHostContext = new CustomLoaderModuleResolutionHostAdapter(
+      options.readResource, options.host
+    );
+    const cliOptions: NgcCliOptions = {
+      i18nFormat: options.i18nFormat,
+      i18nFile: options.i18nFile,
+      locale: options.locale,
+      basePath: options.basePath
+    };
+
+    // Create the Code Generator.
+    const codeGenerator = CodeGenerator.create(
+      options.angularCompilerOptions,
+      cliOptions,
+      options.program,
+      options.host,
+      hostContext
+    );
+
+    return codeGenerator.codegen();
+  }
+
+
+  /**
+   * @internal
+   * @private
+   */
+  static listLazyRoutes(options: NgTools_InternalApi_NG2_ListLazyRoutes_Options)
+      : NgTools_InternalApi_NG_2_LazyRouteMap {
+    const angularCompilerOptions = options.angularCompilerOptions;
+    const program = options.program;
+
+    const moduleResolutionHost = new ModuleResolutionHostAdapter(options.host);
+    const usePathMapping = !!angularCompilerOptions.rootDirs && angularCompilerOptions.rootDirs.length > 0;
+    const ngCompilerHost: AotCompilerHost = usePathMapping
+      ? new PathMappedCompilerHost(program, angularCompilerOptions, moduleResolutionHost)
+      : new CompilerHost(program, angularCompilerOptions, moduleResolutionHost);
+
+    const staticReflector = new StaticReflector(ngCompilerHost);
+    const routeMap = listLazyRoutesOfModule(options.entryModule, ngCompilerHost, staticReflector);
+
+    return Object.keys(routeMap)
+      .reduce((acc: NgTools_InternalApi_NG_2_LazyRouteMap, route: string) => {
+        acc[route] = routeMap[route].absoluteFilePath;
+        return acc;
+      }, {});
+  }
+}