fix: tarball download not working on Firefox and Edge (#144)

* fix tarball download not working on firefox and edge

* update lastModified to be a date number

src/utils/url.ts

@@ -23,15 +23,37 @@ export function extractFileName(url: string): string {
   return url.substring(url.lastIndexOf('/') + 1);
 }
 
+function blobToFile(blob: Blob, fileName: string): File {
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
+  const b: any = blob;
+  b.lastModified = Date.now();
+  b.name = fileName;
+  return b as File;
+}
+
 export function downloadFile(fileStream: Blob, fileName: string): void {
-  const file = new File([fileStream], fileName, { type: 'application/octet-stream', lastModified: Date.now() });
+  let file: File;
+  // File constructor is not supported by Edge
+  // https://developer.mozilla.org/en-US/docs/Web/API/File#Browser_compatibility
+  if (navigator.msSaveBlob) {
+    // Detect if Edge
+    file = blobToFile(new Blob([fileStream], { type: 'application/octet-stream' }), fileName);
+  } else {
+    file = new File([fileStream], fileName, { type: 'application/octet-stream', lastModified: Date.now() });
+  }
+
   const objectURL = URL.createObjectURL(file);
   const fileLink = document.createElement('a');
   fileLink.href = objectURL;
   fileLink.download = fileName;
+
+  // Without appending to an HTML Element, download dialog does not show up on Firefox
+  // https://github.com/verdaccio/ui/issues/119
+  document.documentElement.appendChild(fileLink);
   fileLink.click();
   // firefox requires remove the object url
   setTimeout(() => {
     URL.revokeObjectURL(objectURL);
+    document.documentElement.removeChild(fileLink);
   }, 150);
 }