Hello gridfs lib + fsHooks for mongodb bucket storage

models/lib/fsHooks/createInterceptDownload.js

@@ -0,0 +1,47 @@
+import { createObjectId } from '../grid/createObjectId';
+
+const createInterceptDownload = bucket =>
+  function interceptDownload(http, file, versionName) {
+    const { gridFsFileId } = file.versions[versionName].meta || {};
+    if (gridFsFileId) {
+      // opens the download stream using a given gfs id
+      // see: http://mongodb.github.io/node-mongodb-native/3.2/api/GridFSBucket.html#openDownloadStream
+      const gfsId = createObjectId({ gridFsFileId });
+      const readStream = bucket.openDownloadStream(gfsId);
+
+      readStream.on('data', data => {
+        http.response.write(data);
+      });
+
+      readStream.on('end', () => {
+        http.response.end(); // don't pass parameters to end() or it will be attached to the file's binary stream
+      });
+
+      readStream.on('error', () => {
+        // not found probably
+        // eslint-disable-next-line no-param-reassign
+        http.response.statusCode = 404;
+        http.response.end('not found');
+      });
+
+      http.response.setHeader('Cache-Control', this.cacheControl);
+      http.response.setHeader(
+        'Content-Disposition',
+        getContentDisposition(file.name, http?.params?.query?.download),
+      );
+    }
+    return Boolean(gridFsFileId); // Serve file from either GridFS or FS if it wasn't uploaded yet
+  };
+
+/**
+ * Will initiate download, if links are called with ?download="true" queryparam.
+ **/
+const getContentDisposition = (name, downloadFlag) => {
+  const dispositionType = downloadFlag === 'true' ? 'attachment;' : 'inline;';
+
+  const encodedName = encodeURIComponent(fileName);
+  const dispositionName = `filename="${encodedName}"; filename=*UTF-8"${encodedName}";`;
+  const dispositionEncoding = 'charset=utf-8';
+
+  return `${dispositionType} ${dispositionName} ${dispositionEncoding}`;
+};