chore: allow downloading of autoradiographs

deploy/datasets/index.js

@@ -132,6 +132,12 @@ datasetsRouter.get('/previewFile', cacheMaxAge24Hr, (req, res) => {
   const { file } = req.query
   const filePath = previewFileMap.get(file)
 
+  // Set content type to give browser a hint for download
+  const ext = path.extname(filePath).slice(1)
+  const type = express.static.mime.types[ext]
+
+  if (type) res.setHeader('Content-Type', type)
+
   // even though req.url is modified, req.query is not
   // for now, just serve non encoded image
 

src/ui/databrowserModule/fileviewer/fileviewer.component.ts

@@ -32,7 +32,10 @@ export class FileViewer implements OnChanges{
     private cdr: ChangeDetectorRef,
     @Optional() @Inject(MAT_DIALOG_DATA) data
   ){
-    if (data) this.previewFile = data.previewFile
+    if (data) {
+      this.previewFile = data.previewFile
+      this.downloadUrl = this.previewFile.url
+    }
   }
 
   public downloadUrl: string

src/ui/databrowserModule/fileviewer/fileviewer.template.html

@@ -86,6 +86,10 @@
     <i class="fas fa-file-csv"></i>
   </a>
 
+  <!-- nb -->
+  <!-- cross origin download attribute will be ignored -->
+  <!-- this effective means that when dev on localhost:8080, resource request to localhost:3000 will always open in a new window -->
+  <!-- link: https://developers.google.com/web/updates/2018/02/chrome-65-deprecations#block_cross-origin_wzxhzdk5a_download -->
   <a mat-icon-button
     *ngIf="downloadUrl"
     [href]="downloadUrl"