📷 fix: Pass Base64 to Gemini Vision Payload when using CDN URLs (danny-avila#1705)

Author: danny-avila

api/server/services/Files/images/encode.js

@@ -1,5 +1,27 @@
+const axios = require('axios');
 const { EModelEndpoint, FileSources } = require('librechat-data-provider');
 const { getStrategyFunctions } = require('../strategies');
+const { logger } = require('~/config');
+
+/**
+ * Fetches an image from a URL and returns its base64 representation.
+ *
+ * @async
+ * @param {string} url The URL of the image.
+ * @returns {Promise<string>} The base64-encoded string of the image.
+ * @throws {Error} If there's an issue fetching the image or encoding it.
+ */
+async function fetchImageToBase64(url) {
+  try {
+    const response = await axios.get(url, {
+      responseType: 'arraybuffer',
+    });
+    return Buffer.from(response.data).toString('base64');
+  } catch (error) {
+    logger.error('Error fetching image to convert to base64', error);
+    throw error;
+  }
+}
 
 /**
  * Encodes and formats the given files.
@@ -26,6 +48,13 @@ async function encodeAndFormat(req, files, endpoint) {
     }
 
     encodingMethods[source] = prepareImagePayload;
+
+    /* Google doesn't support passing URLs to payload */
+    if (source !== FileSources.local && endpoint === EModelEndpoint.google) {
+      const [_file, imageURL] = await prepareImagePayload(req, file);
+      promises.push([_file, await fetchImageToBase64(imageURL)]);
+      continue;
+    }
     promises.push(prepareImagePayload(req, file));
   }