Allow multiple file upload (WIP)

src/middlewares/openapi.multipart.ts

@@ -7,6 +7,7 @@ import {
   ValidationError,
 } from '../framework/types';
 import { MulterError } from 'multer';
+
 const multer = require('multer');
 
 export function multipart(
@@ -32,13 +33,31 @@ export function multipart(
           //
           // This is a bit complex because the schema may be defined inline (easy) or via a $ref (complex) in which
           // case we must follow the $ref to check the type.
+
           if (req.files) {
-            // add files to body
-            (<Express.Multer.File[]>req.files).forEach(
-              (f: Express.Multer.File) => {
-                req.body[f.fieldname] = '';
-              },
-            );
+
+            // to handle single and multiple file upload at the same time, let us this initialize this count variable
+            // for example { "files": 5 }
+            const count_by_fieldname = (<Express.Multer.File[]>req.files)
+              .map(file => file.fieldname)
+              .reduce((acc, curr) => {
+                acc[curr] = (acc[curr] || 0) + 1;
+                return acc;
+              }, {});
+
+            // add file(s) to body
+            Object
+              .entries(count_by_fieldname)
+              .forEach(
+                ([fieldname, count]: [string, number]) => {
+                  // TODO maybe also check in the api doc if it is a single upload or multiple
+                  const is_multiple = count > 1;
+                  req.body[fieldname] = (is_multiple)
+                    ? new Array(count).fill('')
+                    : '';
+                },
+              );
+
           }
           next();
         }