fix: concurrent cy.prompt() and Studio bundle download issues

packages/driver/src/cy/commands/prompt/index.ts

@@ -63,23 +63,29 @@ const initializeModule = async (Cypress: Cypress.Cypress): Promise<CyPromptDrive
     })
   }
 
+  let module: CyPromptDriver | null = null
+
   // Once the cy prompt bundle is downloaded and ready,
   // we can initialize it via the module federation runtime
-  init({
-    remotes: [{
-      alias: 'cy-prompt',
-      type: 'module',
-      name: 'cy-prompt',
-      entryGlobalName: 'cy-prompt',
-      entry: '/__cypress-cy-prompt/driver/cy-prompt.js',
-      shareScope: 'default',
-    }],
-    name: 'driver',
-  })
-
-  // This cy-prompt.js file and any subsequent files are
-  // served from the cy prompt bundle.
-  const module = await loadRemote<CyPromptDriver>('cy-prompt')
+  try {
+    init({
+      remotes: [{
+        alias: 'cy-prompt',
+        type: 'module',
+        name: 'cy-prompt',
+        entryGlobalName: 'cy-prompt',
+        entry: '/__cypress-cy-prompt/driver/cy-prompt.js',
+        shareScope: 'default',
+      }],
+      name: 'driver',
+    })
+
+    // This cy-prompt.js file and any subsequent files are
+    // served from the cy prompt bundle.
+    module = await loadRemote<CyPromptDriver>('cy-prompt')
+  } catch (error) {
+    $errUtils.throwErrByPath('prompt.promptBundleNeedsRefresh')
+  }
 
   if (!module?.default) {
     $errUtils.throwErrByPath('prompt.promptDownloadError', {

packages/driver/src/cypress/error_messages.ts

@@ -1354,6 +1354,11 @@ export default {
         docsUrl: 'https://on.cypress.io/prompt-download-error',
       }
     },
+    promptBundleNeedsRefresh: stripIndent`\
+      Your \`cy.prompt\` Cloud code needs to be refreshed.
+
+      Please restart the app to get the latest version.
+    `,
     promptProxyError: {
       message: stripIndent`\
       \`cy.prompt\` requires an internet connection. To continue, you may need to configure Cypress with your proxy settings.

packages/server/lib/cloud/cy-prompt/ensure_cy_prompt_bundle.ts

@@ -1,9 +1,8 @@
-import { remove, ensureDir, readFile, pathExists } from 'fs-extra'
-
-import tar from 'tar'
+import { ensureDir, readFile, pathExists } from 'fs-extra'
 import { getCyPromptBundle } from '../api/cy-prompt/get_cy_prompt_bundle'
 import path from 'path'
 import { verifySignature } from '../encryption'
+import { extractAtomic } from '../extract_atomic'
 
 interface EnsureCyPromptBundleOptions {
   cyPromptPath: string
@@ -21,8 +20,6 @@ interface EnsureCyPromptBundleOptions {
 export const ensureCyPromptBundle = async ({ cyPromptPath, cyPromptUrl, projectId }: EnsureCyPromptBundleOptions): Promise<Record<string, string>> => {
   const bundlePath = path.join(cyPromptPath, 'bundle.tar')
 
-  // First remove cyPromptPath to ensure we have a clean slate
-  await remove(cyPromptPath)
   await ensureDir(cyPromptPath)
 
   const responseManifestSignature: string = await getCyPromptBundle({
@@ -31,10 +28,7 @@ export const ensureCyPromptBundle = async ({ cyPromptPath, cyPromptUrl, projectI
     bundlePath,
   })
 
-  await tar.extract({
-    file: bundlePath,
-    cwd: cyPromptPath,
-  })
+  await extractAtomic(bundlePath, cyPromptPath)
 
   const manifestPath = path.join(cyPromptPath, 'manifest.json')
 

packages/server/lib/cloud/extract_atomic.ts

@@ -0,0 +1,52 @@
+import { createReadStream } from 'fs'
+import tar from 'tar'
+import { ensureDir } from 'fs-extra'
+import path from 'path'
+import writeFileAtomic from 'write-file-atomic'
+
+export const extractAtomic = async (archivePath: string, destinationPath: string) => {
+  const entryPromises: Promise<void>[] = []
+
+  const parser = new tar.Parse()
+
+  parser.on('entry', (entry) => {
+    if (entry.type !== 'File') {
+      entry.resume() // skip non-files
+
+      return
+    }
+
+    const targetPath = path.join(destinationPath, entry.path)
+
+    const p = (async () => {
+      await ensureDir(path.dirname(targetPath))
+
+      const chunks: Buffer[] = []
+
+      for await (const chunk of entry) {
+        chunks.push(chunk)
+      }
+
+      const content = Buffer.concat(chunks)
+
+      await writeFileAtomic(targetPath, content, {
+        mode: entry.mode || 0o644,
+      })
+    })()
+
+    entryPromises.push(p)
+  })
+
+  // Pipe archive into parser
+  const stream = createReadStream(archivePath)
+
+  stream.pipe(parser)
+
+  // Wait for parser to finish and all entry writes to complete
+  await new Promise<void>((resolve, reject) => {
+    parser.on('end', resolve)
+    stream.on('error', reject)
+  })
+
+  await Promise.all(entryPromises)
+}

packages/server/lib/cloud/studio/ensure_studio_bundle.ts

@@ -4,6 +4,7 @@ import tar from 'tar'
 import { getStudioBundle } from '../api/studio/get_studio_bundle'
 import path from 'path'
 import { verifySignature } from '../encryption'
+import { extractAtomic } from '../extract_atomic'
 
 interface EnsureStudioBundleOptions {
   studioUrl: string
@@ -25,19 +26,14 @@ export const ensureStudioBundle = async ({
 }: EnsureStudioBundleOptions): Promise<Record<string, string>> => {
   const bundlePath = path.join(studioPath, 'bundle.tar')
 
-  // First remove studioPath to ensure we have a clean slate
-  await remove(studioPath)
   await ensureDir(studioPath)
 
   const responseManifestSignature = await getStudioBundle({
     studioUrl,
     bundlePath,
   })
 
-  await tar.extract({
-    file: bundlePath,
-    cwd: studioPath,
-  })
+  await extractAtomic(bundlePath, studioPath)
 
   const manifestPath = path.join(studioPath, 'manifest.json')
 

packages/server/package.json

@@ -138,7 +138,8 @@
     "wait-port": "1.1.0",
     "webdriver": "9.14.0",
     "webpack-virtual-modules": "0.5.0",
-    "widest-line": "3.1.0"
+    "widest-line": "3.1.0",
+    "write-file-atomic": "7.0.0"
   },
   "devDependencies": {
     "@babel/core": "7.28.0",