[WEB + CLSI] Download as docx file feature (#32851)

* using CLSI logic for fetching the project contents and skip the .zip export

* Use unique conversion directory for project-to-docx export to avoid corrupting the shared compile
  directory when a compile runs concurrently

* Remove X-Accel-Buffering header — not needed as CLSI does not run behind nginx

* moving log before sending the data

* Return CLSI stream directly instead of buffering to disk on web

  Previously convertProjectToDocx wrote the CLSI response to a temp file
  on disk, then the controller read it back to stream to the client.
  Now the stream is returned directly and piped to the response,
  avoiding unnecessary disk I/O on the web server.

* Use href redirect for docx export instead of fetching blob into memory

* making functions and files more generic so they can be used in future for other documents exports as well

* adding export-docx split test

* adding unit tests

* adding cypress E2E test

* format:fix

* renaming the route to download from convert

* adding new icon for export docx button

* format:fix

* remove unused showExportDocumentErrorToast export and adding guard against invalid Content-Length header from CLSI

* format:fix

* refactor(clsi): move promisify(parse) into RequestParser

* refactor: generic conversion endpoint with type as route
  param

* refactor: use type→extension map for validated conversion types

* refactor(clsi): remove --standalone flag and fix rejection test

* fixing the href in cypress test

* renaming function

* adding type to Metrics.inc

* fix: rename exportProjectDocument, add WithLock wrapper and metrics type label

* format:fix

* fix: hide docx export from anonymous users and add WithLock wrapper

* format fix

* remove redundant Content-Length validation from DocumentConversionManager

* format:fix

* removing trailing icon

GitOrigin-RevId: e9764fefac2c4b625d23be9e942ea4a8b283c70d

services/clsi/app/js/ConversionController.js

@@ -3,10 +3,14 @@ import { expressify } from '@overleaf/promise-utils'
 import fs from 'node:fs/promises'
 import fsSync from 'node:fs'
 import ConversionManager from './ConversionManager.js'
+import ResourceWriter from './ResourceWriter.js'
+import RequestParser from './RequestParser.js'
 import { pipeline } from 'node:stream/promises'
 import Settings from '@overleaf/settings'
 import Path from 'node:path'
 
+const SUPPORTED_CONVERSION_TYPES = new Map([['docx', 'docx']])
+
 async function convertDocxToLaTeX(req, res) {
   const { path } = req.file
   if (!Settings.enablePandocConversions) {
@@ -41,6 +45,59 @@ async function convertDocxToLaTeX(req, res) {
   }
 }
 
+async function convertProjectToDocument(req, res) {
+  if (!Settings.enablePandocConversions) {
+    return res.sendStatus(404)
+  }
+
+  const type = req.query.type
+  const extension = SUPPORTED_CONVERSION_TYPES.get(type)
+  if (!extension) {
+    return res.sendStatus(400)
+  }
+
+  const request = await RequestParser.promises.parse(req.body)
+  request.project_id = req.params.project_id
+  request.user_id = req.params.user_id
+  request.metricsOpts = {}
+
+  const conversionId = crypto.randomUUID()
+  const conversionDir = Path.join(Settings.path.compilesDir, conversionId)
+
+  logger.debug(
+    {
+      projectId: request.project_id,
+      userId: request.user_id,
+      rootResourcePath: request.rootResourcePath,
+      type,
+    },
+    'syncing resources for project-to-document conversion'
+  )
+
+  try {
+    await ResourceWriter.promises.syncResourcesToDisk(request, conversionDir)
+
+    const documentPath =
+      await ConversionManager.promises.convertLaTeXToDocumentInDirWithLock(
+        conversionId,
+        conversionDir,
+        request.rootResourcePath,
+        type,
+        extension
+      )
+
+    const documentStat = await fs.stat(documentPath)
+    res.setHeader('Content-Length', documentStat.size)
+    res.attachment(`output.${extension}`)
+    res.setHeader('X-Content-Type-Options', 'nosniff')
+    const readStream = fsSync.createReadStream(documentPath)
+    await pipeline(readStream, res)
+  } finally {
+    await fs.rm(conversionDir, { recursive: true, force: true }).catch(() => {})
+  }
+}
+
 export default {
   convertDocxToLaTeX: expressify(convertDocxToLaTeX),
+  convertProjectToDocument: expressify(convertProjectToDocument),
 }