⬇️ feat: Assistant File Downloads (#2234)

* WIP: basic route for file downloads and file strategy for generating readablestream to pipe as res

* chore(DALLE3): add typing for OpenAI client

* chore: add `CONSOLE_JSON` notes to dotenv.md

* WIP: first pass OpenAI Assistants File Output handling

* feat: first pass assistants output file download from openai

* chore: yml vs. yaml variation to .gitignore for `librechat.yml`

* refactor(retrieveAndProcessFile): remove redundancies

* fix(syncMessages): explicit sort of apiMessages to fix message order on abort

* chore: add logs for warnings and errors, show toast on frontend

* chore: add logger where console was still being used

api/server/routes/files/files.js

@@ -1,12 +1,13 @@
-const axios = require('axios');
 const fs = require('fs').promises;
 const express = require('express');
-const { isUUID } = require('librechat-data-provider');
+const { isUUID, FileSources } = require('librechat-data-provider');
 const {
   filterFile,
   processFileUpload,
   processDeleteRequest,
 } = require('~/server/services/Files/process');
+const { initializeClient } = require('~/server/services/Endpoints/assistants');
+const { getStrategyFunctions } = require('~/server/services/Files/strategies');
 const { getFiles } = require('~/models/File');
 const { logger } = require('~/config');
 
@@ -65,28 +66,63 @@ router.delete('/', async (req, res) => {
   }
 });
 
-router.get('/download/:fileId', async (req, res) => {
+router.get('/download/:userId/:filepath', async (req, res) => {
   try {
-    const { fileId } = req.params;
+    const { userId, filepath } = req.params;
 
-    const options = {
-      headers: {
-        // TODO: Client initialization for OpenAI API Authentication
-        Authorization: `Bearer ${process.env.OPENAI_API_KEY}`,
-      },
-      responseType: 'stream',
+    if (userId !== req.user.id) {
+      logger.warn(`${errorPrefix} forbidden: ${file_id}`);
+      return res.status(403).send('Forbidden');
+    }
+
+    const parts = filepath.split('/');
+    const file_id = parts[2];
+    const [file] = await getFiles({ file_id });
+    const errorPrefix = `File download requested by user ${userId}`;
+
+    if (!file) {
+      logger.warn(`${errorPrefix} not found: ${file_id}`);
+      return res.status(404).send('File not found');
+    }
+
+    if (!file.filepath.includes(userId)) {
+      logger.warn(`${errorPrefix} forbidden: ${file_id}`);
+      return res.status(403).send('Forbidden');
+    }
+
+    if (file.source === FileSources.openai && !file.model) {
+      logger.warn(`${errorPrefix} has no associated model: ${file_id}`);
+      return res.status(400).send('The model used when creating this file is not available');
+    }
+
+    const { getDownloadStream } = getStrategyFunctions(file.source);
+    if (!getDownloadStream) {
+      logger.warn(`${errorPrefix} has no stream method implemented: ${file.source}`);
+      return res.status(501).send('Not Implemented');
+    }
+
+    const setHeaders = () => {
+      res.setHeader('Content-Disposition', `attachment; filename="${file.filename}"`);
+      res.setHeader('Content-Type', 'application/octet-stream');
     };
 
-    const fileResponse = await axios.get(`https://api.openai.com/v1/files/${fileId}`, {
-      headers: options.headers,
-    });
-    const { filename } = fileResponse.data;
-
-    const response = await axios.get(`https://api.openai.com/v1/files/${fileId}/content`, options);
-    res.setHeader('Content-Disposition', `attachment; filename="${filename}"`);
-    response.data.pipe(res);
+    /** @type {{ body: import('stream').PassThrough } | undefined} */
+    let passThrough;
+    /** @type {ReadableStream | undefined} */
+    let fileStream;
+    if (file.source === FileSources.openai) {
+      req.body = { model: file.model };
+      const { openai } = await initializeClient({ req, res });
+      passThrough = await getDownloadStream(file_id, openai);
+      setHeaders();
+      passThrough.body.pipe(res);
+    } else {
+      fileStream = getDownloadStream(file_id);
+      setHeaders();
+      fileStream.pipe(res);
+    }
   } catch (error) {
-    console.error('Error downloading file:', error);
+    logger.error('Error downloading file:', error);
     res.status(500).send('Error downloading file');
   }
 });