Simplify image resolver code

.changeset/red-onions-exist.md

@@ -0,0 +1,5 @@
+---
+'@keystone-next/fields': patch
+---
+
+Simplified image input resolver.

packages-next/fields/src/types/image/Implementation.ts

@@ -1,8 +1,8 @@
+import { FileUpload } from 'graphql-upload';
 import { PrismaFieldAdapter, PrismaListAdapter } from '@keystone-next/adapter-prisma-legacy';
 import { getImageRef, SUPPORTED_IMAGE_EXTENSIONS } from '@keystone-next/utils-legacy';
 import { ImageData, KeystoneContext, BaseKeystoneList } from '@keystone-next/types';
 import { Implementation } from '../../Implementation';
-import { handleImageData } from './handle-image-input';
 
 export class ImageImplementation<P extends string> extends Implementation<P> {
   get _supportsUnique() {
@@ -85,8 +85,22 @@ export class ImageImplementation<P extends string> extends Implementation<P> {
     if (data === undefined) {
       return undefined;
     }
-    const imageData = await handleImageData(data, context);
-    return imageData;
+
+    type ImageInput = {
+      upload?: Promise<FileUpload> | null;
+      ref?: string | null;
+    };
+    const { ref, upload }: ImageInput = data;
+    if (ref) {
+      if (upload) {
+        throw new Error('Only one of ref and upload can be passed to ImageFieldInput');
+      }
+      return context.images!.getDataFromRef(ref);
+    }
+    if (!upload) {
+      throw new Error('Either ref or upload must be passed to ImageFieldInput');
+    }
+    return context.images!.getDataFromStream((await upload).createReadStream());
   }
 
   gqlUpdateInputFields() {