Catch error when file is null or undefined

wiki/src/install/inc/js/download.js

@@ -116,6 +116,9 @@ document.addEventListener("DOMContentLoaded", function() {
     else if (result === "failed-again") {
       show(document.getElementById("verification-failed-again"));
     }
+    else if (result === "error-file") {
+      show(document.getElementById("verification-error-file"));
+    }
     else if (result === "error-json") {
       show(document.getElementById("verification-error-json"));
       document.getElementById("checksum-file").setAttribute("href", URLofJsonFileContainingChecksums);
@@ -131,6 +134,7 @@ document.addEventListener("DOMContentLoaded", function() {
     hide(document.getElementById("verification-successful"));
     hide(document.getElementById("verification-failed"));
     hide(document.getElementById("verification-failed-again"));
+    hide(document.getElementById("verification-error-file"));
     hide(document.getElementById("verification-error-json"));
     hide(document.getElementById("verification-error-image"));
     show(document.getElementById("verification"));
@@ -147,8 +151,14 @@ document.addEventListener("DOMContentLoaded", function() {
   /* Verification logic functions */
 
   async function verifyFile(e, elm) {
-    file = elm.files[0]
-    showVerifyingDownload(file.name);
+
+    try {
+      file = elm.files[0];
+      showVerifyingDownload(file.name);
+    } catch(err) {
+      showVerificationResult("error-file");
+      return;
+    }
 
     try {
       var response=await fetch(URLofJsonFileContainingChecksums);
@@ -306,5 +316,6 @@ document.addEventListener("DOMContentLoaded", function() {
   // showVerificationResult("failed-again");
   // showVerificationResult("error-json");
   // showVerificationResult("error-image");
+  // verifyFile(null, null);
 
 });

wiki/src/install/inc/steps/download.inline.html

@@ -145,6 +145,12 @@ were solved, and known issues that have already been identified.</p>
       </div>
       <p>Please try to download again from a different place or a different computer&hellip;</p>
     </div>
+    <div id="verification-error-file" class="block">
+      <p>[[!img lib/cross.png class="icon" link="no" alt=""]]<b>Error selecting image.</b></p>
+      <p class="usb upgrade download-only-img">Make sure that you select a USB image that is readable by your browser.</p>
+      <p class="dvd vm download-only-iso">Make sure that you select an ISO image that is readable by your browser.</p>
+      <p><a id="retry-json">Retry&hellip;</a></p>
+    </div>
     <div id="verification-error-json" class="block">
       <p>[[!img lib/cross.png class="icon" link="no" alt=""]]<b>Error downloading <a id="checksum-file" href="">checksum file</a> from our website.</b></p>
       <p>Make sure that your browser is connected to the Internet.</p>

wiki/src/install/inc/stylesheets/download.css

@@ -18,6 +18,7 @@
 #verification-successful,
 #verification-failed,
 #verification-failed-again,
+#verification-error-file,
 #verification-error-json,
 #verification-error-image,
 #skip-download,
@@ -147,7 +148,7 @@ img.icon {
   vertical-align: bottom;
 }
 
-#verification-error-json, #verification-error-image {
+#verification-error-file, #verification-error-json, #verification-error-image {
   margin-top: 1.5em;
 }