Add progress bar for file upload.

app/static/js/opaque.js

@@ -0,0 +1,30 @@
+function sendNewJobFormData(form, progress) {
+  var XHR = new XMLHttpRequest();
+  var FD = new FormData(form);
+  XHR.upload.addEventListener("progress", function(event) {
+    progress.querySelector(".determinate").style.width = ((event.loaded / event.total) * 100).toString() + "%";
+  });
+  XHR.addEventListener("loadend", function(event) {
+    form.reset();
+    location.reload();
+  });
+  XHR.open("POST", window.location.href);
+  XHR.send(FD);
+}
+function initNewJobForm(newJobFormElement) {
+  newJobFormElement.addEventListener("submit", function(event) {
+    event.preventDefault();
+    var toast = M.toast(
+      {html: `<div class="row">
+                <div class="col s12">${this.title.value}</div>
+                <div class="col s12">
+                  <div class="progress">
+                    <div class="determinate" style="width: 0%"></div>
+                  </div>
+                </div>
+              </div>`,
+       displayLength: Infinity}
+    );
+    sendNewJobFormData(this, toast.el.querySelector(".progress"));
+  });
+}