refactor: version with fallback

Author: atlj

packages/create-react-native-library/src/index.ts

@@ -17,8 +17,9 @@ import { version } from '../package.json';
 import { addCodegenBuildScript } from './utils/addCodegenBuildScript';
 import { createInitialGitCommit } from './utils/initialCommit';
 import { assertNpx } from './utils/assert';
+import { resolveBobVersionWithFallback } from './utils/promiseWithFallback';
 
-const FALLBACK_BOB_VERSION = '0.29.0';
+const FALLBACK_BOB_VERSION = '0.32.0';
 
 const BINARIES = [
  /(gradlew|\.(jar|keystore|png|jpg|gif))$/,
@@ -276,12 +277,7 @@ async function create(_argv: yargs.Arguments<any>) {
  const { _, $0, ...argv } = _argv;
 
  // Prefetch bob version in background while asking questions
- const bobVersionPromise = spawn('npm', [
- 'view',
- 'react-native-builder-bob',
- 'dist-tags.latest',
- ]);
-
+ const resolveBobVersion = resolveBobVersionWithFallback(FALLBACK_BOB_VERSION);
  let local = false;
 
  if (typeof argv.local === 'boolean') {
@@ -531,21 +527,6 @@ async function create(_argv: yargs.Arguments<any>) {
  reactNativeVersion,
  } = answers;
 
- // Get latest version of Bob from NPM
- let bobVersion: string;
-
- try {
- bobVersion = await Promise.race([
- new Promise<string>((resolve) => {
- setTimeout(() => resolve(FALLBACK_BOB_VERSION), 1000);
- }),
- bobVersionPromise,
- ]);
- } catch (e) {
- // Fallback to a known version if we couldn't fetch
- bobVersion = FALLBACK_BOB_VERSION;
- }
-
  const moduleType = type.startsWith('view-') ? 'view' : 'module';
  const arch =
  type === 'module-new' || type === 'view-new'
@@ -570,9 +551,10 @@ async function create(_argv: yargs.Arguments<any>) {
  .replace(/[^a-z0-9]/g, '')
  .toLowerCase()}`;
 
+ const bobVersion = await resolveBobVersion();
  const options = {
  bob: {
- version: bobVersion || FALLBACK_BOB_VERSION,
+ version: bobVersion,
  },
  project: {
  slug,

packages/create-react-native-library/src/utils/promiseWithFallback.ts

@@ -0,0 +1,32 @@
+import { spawn } from './spawn';
+
+export function promiseWithFallback<T>(
+ promise: Promise<T>,
+ fallback: T,
+ timeout: number
+): () => Promise<T> {
+ async function forceResolve() {
+ let result: T;
+
+ try {
+ result = await Promise.race([
+ new Promise<T>((resolve) => {
+ setTimeout(() => resolve(fallback), timeout);
+ }),
+ promise,
+ ]);
+ } catch (e) {
+ result = fallback;
+ }
+ return result;
+ }
+
+ return forceResolve;
+}
+
+export const resolveBobVersionWithFallback = (fallback: string) =>
+ promiseWithFallback(
+ spawn('npm', ['view', 'react-native-builder-bob', 'dist-tags.latest']),
+ fallback,
+ 1000
+ );