backend-common: make ReadTreeResponse.dir() accept an options object instead

packages/backend-common/src/reading/GithubUrlReader.test.ts

@@ -293,7 +293,7 @@ describe('GithubUrlReader', () => {
       );
 
       mockfs();
-      const directory = await response.dir('/tmp/fs');
+      const directory = await response.dir({ targetDir: '/tmp/fs' });
 
       const writtenToDirectory = fs.existsSync(directory);
       const paths = await recursive(directory);

packages/backend-common/src/reading/GithubUrlReader.ts

@@ -18,7 +18,13 @@ import { Config } from '@backstage/config';
 import parseGitUri from 'git-url-parse';
 import fetch from 'cross-fetch';
 import { NotFoundError } from '../errors';
-import { ReaderFactory, ReadTreeResponse, UrlReader, File } from './types';
+import {
+  ReaderFactory,
+  ReadTreeResponse,
+  UrlReader,
+  File,
+  ReadTreeResponseDirOptions,
+} from './types';
 import tar from 'tar';
 import fs from 'fs-extra';
 import concatStream from 'concat-stream';
@@ -294,9 +300,10 @@ export class GithubUrlReader implements UrlReader {
               resolve(Buffer.from('Archive is not yet implemented')),
             );
           },
-          dir: (outDir: string | undefined) => {
+          dir: (options?: ReadTreeResponseDirOptions) => {
             const targetDirectory =
-              outDir || fs.mkdtempSync(path.join(os.tmpdir(), 'backstage-'));
+              options?.targetDir ||
+              fs.mkdtempSync(path.join(os.tmpdir(), 'backstage-'));
 
             return new Promise((res, rej) => {
               Promise.all(

packages/backend-common/src/reading/types.ts

@@ -17,6 +17,11 @@
 import { Logger } from 'winston';
 import { Config } from '@backstage/config';
 
+export type ReadTreeOptions = {
+  /** A filter that can be used to select which files should be extracted. By default all files are extracted */
+  filter?(path: string): boolean;
+};
+
 /**
  * A generic interface for fetching plain data from URLs.
  */
@@ -48,8 +53,13 @@ export type File = {
   content(): Promise<Buffer>;
 };
 
+export type ReadTreeResponseDirOptions = {
+  /** The directory to write files to. Defaults to the OS tmpdir or `backend.workingDirectory` if set in config */
+  targetDir?: string;
+};
+
 export type ReadTreeResponse = {
   files(): Promise<File[]>;
   archive(): Promise<Buffer>;
-  dir(outDir?: string): Promise<string>;
+  dir(options?: ReadTreeResponseDirOptions): Promise<string>;
 };