Index: openacs-4/packages/proctoring-support/proctoring-support.info
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/proctoring-support/proctoring-support.info,v
diff -u -r1.1.2.35 -r1.1.2.36
--- openacs-4/packages/proctoring-support/proctoring-support.info	8 Mar 2022 13:01:00 -0000	1.1.2.35
+++ openacs-4/packages/proctoring-support/proctoring-support.info	24 May 2023 14:06:20 -0000	1.1.2.36
@@ -10,7 +10,7 @@
     <inherit-templates-p>f</inherit-templates-p>
     <auto-mount>proctoring</auto-mount>
 
-    <version name="3.4.7" url="http://openacs.org/repository/download/apm/proctoring-support-3.4.7.apm">
+    <version name="3.5.0" url="http://openacs.org/repository/download/apm/proctoring-support-3.5.0.apm">
         <owner url="mailto:apisano@wu.ac.at">Antonio Pisano</owner>
         <summary>Set of tools to implement proctoring of user interaction</summary>
         <vendor url="https://www.wu.ac.at/">Wirtschaftsuniversität Wien</vendor>
@@ -21,7 +21,7 @@
 No real UI is provided by the package itself. Other packages must integrate the provided includes.</description>
         <maturity>0</maturity>
 
-        <provides url="proctoring-support" version="3.4.7"/>
+        <provides url="proctoring-support" version="3.5.0"/>
         <requires url="acs-templating" version="5.10.0"/>
         <requires url="xotcl-core" version="5.10.0"/>
 
Index: openacs-4/packages/proctoring-support/catalog/proctoring-support.de_DE.ISO-8859-1.xml
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/proctoring-support/catalog/proctoring-support.de_DE.ISO-8859-1.xml,v
diff -u -r1.1.2.23 -r1.1.2.24
--- openacs-4/packages/proctoring-support/catalog/proctoring-support.de_DE.ISO-8859-1.xml	8 Mar 2022 13:01:00 -0000	1.1.2.23
+++ openacs-4/packages/proctoring-support/catalog/proctoring-support.de_DE.ISO-8859-1.xml	24 May 2023 14:06:20 -0000	1.1.2.24
@@ -137,6 +137,7 @@
   <msg key="Start_date">Anfangsdatum</msg>
   <msg key="student_id_label">Matrikelnummer</msg>
   <msg key="time_filter_presets_label">Filter</msg>
+  <msg key="too_long_without_sending_artifacts">Es ist zu viel Zeit verstrichen, ohne dass Proctoring-Artefakte gesendet wurden. Diese Sitzung wird abgebrochen. Bitte �berpr�fen Sie Ihre Netzwerkverbindung und Hardwarekonfiguration und versuchen Sie es erneut.</msg>
   <msg key="unflag_all_confirm_msg">Alle Artefakte f�r diesen Benutzer w�rden als in Ordnung best�tigt, sind Sie sicher?</msg>
   <msg key="unflag_all_label">Alle in Ordnung</msg>
   <msg key="unflag_artifact_label">In Ordnung</msg>
Index: openacs-4/packages/proctoring-support/catalog/proctoring-support.en_US.ISO-8859-1.xml
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/proctoring-support/catalog/proctoring-support.en_US.ISO-8859-1.xml,v
diff -u -r1.1.2.25 -r1.1.2.26
--- openacs-4/packages/proctoring-support/catalog/proctoring-support.en_US.ISO-8859-1.xml	2 Mar 2022 17:43:32 -0000	1.1.2.25
+++ openacs-4/packages/proctoring-support/catalog/proctoring-support.en_US.ISO-8859-1.xml	24 May 2023 14:06:20 -0000	1.1.2.26
@@ -142,6 +142,7 @@
   <msg key="Start_date">Start date</msg>
   <msg key="student_id_label">Student ID</msg>
   <msg key="time_filter_presets_label">Time filter presets</msg>
+  <msg key="too_long_without_sending_artifacts">Too much time has passed without sending proctoring artifacts. This session will be aborted. Please check your network connectivity and hardware configuration and try again.</msg>
   <msg key="unflag_all_confirm_msg">This will set all artifacts for this user as OK, are you sure?</msg>
   <msg key="unflag_all_label">Set everything as OK</msg>
   <msg key="unflag_artifact_label">Confirm OK</msg>
Index: openacs-4/packages/proctoring-support/catalog/proctoring-support.it_IT.ISO-8859-1.xml
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/proctoring-support/catalog/proctoring-support.it_IT.ISO-8859-1.xml,v
diff -u -r1.1.2.8 -r1.1.2.9
--- openacs-4/packages/proctoring-support/catalog/proctoring-support.it_IT.ISO-8859-1.xml	2 Mar 2022 17:43:32 -0000	1.1.2.8
+++ openacs-4/packages/proctoring-support/catalog/proctoring-support.it_IT.ISO-8859-1.xml	24 May 2023 14:06:20 -0000	1.1.2.9
@@ -63,6 +63,7 @@
   <msg key="Start_date">Data inizio</msg>
   <msg key="student_id_label">ID Studente</msg>
   <msg key="time_filter_presets_label">Periodi preselezionati</msg>
+  <msg key="too_long_without_sending_artifacts">� trascorso troppo tempo senza che siano stati inviati artefatti di verifica. La sessione verr� interrotta. Si prega di controllare la connettivit� di rete e la configurazione hardware e riprovare.</msg>
   <msg key="unflag_all_confirm_msg">Tutti gli artefatti di questo utente saranno segnati come OK. Vuoi procedere?</msg>
   <msg key="unflag_all_label">Segna tutto come OK</msg>
   <msg key="unflag_artifact_label">Segna come OK</msg>
Index: openacs-4/packages/proctoring-support/lib/proctored-page.adp
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/proctoring-support/lib/proctored-page.adp,v
diff -u -r1.1.2.15 -r1.1.2.16
--- openacs-4/packages/proctoring-support/lib/proctored-page.adp	15 Dec 2022 13:47:29 -0000	1.1.2.15
+++ openacs-4/packages/proctoring-support/lib/proctored-page.adp	24 May 2023 14:06:20 -0000	1.1.2.16
@@ -137,5 +137,6 @@
     const submitLabel = "#proctoring-support.wizard_finish#";
     const acceptLabel = "#proctoring-support.accept#";
     const blackPictureSizeThreshold = 5000; // kbytes
+    const tooLongWithoutSendingArtifactsMessage = `@msg.too_long_without_sending_artifacts@`;
   </script>
   <script src="/resources/proctoring-support/proctored-page.js"></script>
Index: openacs-4/packages/proctoring-support/lib/proctored-page.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/proctoring-support/lib/proctored-page.tcl,v
diff -u -r1.1.2.13 -r1.1.2.14
--- openacs-4/packages/proctoring-support/lib/proctored-page.tcl	12 Jul 2022 14:46:35 -0000	1.1.2.13
+++ openacs-4/packages/proctoring-support/lib/proctored-page.tcl	24 May 2023 14:06:20 -0000	1.1.2.14
@@ -119,6 +119,7 @@
 set default_msg(wrong_display_surface_selected) [_ proctoring-support.wrong_display_surface_selected]
 set default_msg(display_surface_not_supported) [_ proctoring-support.display_surface_not_supported]
 set default_msg(mobile_devices_not_supported) [_ proctoring-support.mobile_devices_are_unsupported]
+set default_msg(too_long_without_sending_artifacts) [_ proctoring-support.too_long_without_sending_artifacts]
 
 foreach {key value} [array get default_msg] {
     if {![info exists msg($key)]} {
Index: openacs-4/packages/proctoring-support/www/resources/proctored-page.js
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/proctoring-support/www/resources/proctored-page.js,v
diff -u -r1.1.2.30 -r1.1.2.31
--- openacs-4/packages/proctoring-support/www/resources/proctored-page.js	15 Dec 2022 13:41:22 -0000	1.1.2.30
+++ openacs-4/packages/proctoring-support/www/resources/proctored-page.js	24 May 2023 14:06:20 -0000	1.1.2.31
@@ -1,10 +1,15 @@
 function modalAlert(message, handler) {
-    document.querySelector('#modal-messages .modal-body').innerHTML = message;
-    const dialog = $('#modal-messages');
-    if (typeof handler === 'function') {
-        dialog.on('hidden.bs.modal', handler);
+    if (typeof jQuery !== 'undefined') {
+        document.querySelector('#modal-messages .modal-body').innerHTML = message;
+        const dialog = $('#modal-messages');
+        if (typeof handler === 'function') {
+            dialog.on('hidden.bs.modal', handler);
+        }
+        dialog.modal('show');
+    } else {
+        alert(message);
+        handler();
     }
-    dialog.modal('show');
 }
 
 function streamMuted(stream) {
@@ -105,6 +110,39 @@
     uploadQueue.push(formData);
 }
 
+
+//
+// In this proctoring implementation we try to tolerate many
+// suboptimal conditions such as lack of Internet connectivity or a
+// temporary downtime of the server.  We also handle exceptions
+// happening at various places on the client side, such as obtaining
+// the picture, making sure streams are active and so on.
+//
+// In the wild we have encountered situations where despite our best
+// efforts the user would be able to proceed through the session
+// without generating proctoring artifacts. Foul play aside, such
+// condition may happen, for instance, if the client suddenly hangs
+// while taking a picture without generating an error. This may be due
+// to various factors such as hardware errors or browser bugs that is
+// difficult to foresee or reproduce. In such unfortunate case, no
+// upload would be scheduled and no error would be thrown.
+//
+// Therefore, we now implement a simple "ground-truth" test: whenever
+// we detect that the client has not been sending artifacts for longer
+// than 10 times the maximum proctoring interval, we inform the user
+// and abort the session.
+//
+let latestSuccessfulUploadTimeout;
+function checkUpload() {
+    clearTimeout(latestSuccessfulUploadTimeout);
+
+    latestSuccessfulUploadTimeout = setTimeout(function () {
+        modalAlert(tooLongWithoutSendingArtifactsMessage, function() {
+            location.reload();
+        });
+    }, maxMsInterval * 10);
+}
+
 function upload() {
     if (!hasUpload) {
         uploadQueue.length = 0;
@@ -140,6 +178,7 @@
                     // Success: reschedule the upload 1s from now.
                     //
                     reschedule(1000);
+                    checkUpload();
                 } else {
                     //
                     // Proctoring is over: redirect to the unproctored
@@ -537,6 +576,7 @@
         proctoring.start();
         console.log('starting upload');
         upload();
+        checkUpload();
         console.log('proctoring has started');
     } else {
         createIframe();