Student browser polls for queued submission result

common/lib/capa/capa/inputtypes.py

@@ -307,7 +307,18 @@ def filesubmission(element, value, status, render_template, msg=''):
     Upload a single file (e.g. for programming assignments)
     '''
     eid = element.get('id')
-    context = { 'id': eid, 'state': status, 'msg': msg, 'value': value, }
+
+    # Check if problem has been queued
+    queued = '' 
+    queue_len = 0
+    if status == 'incomplete': # Flag indicating that the problem has been queued, 'msg' is length of queue
+        queued = 'true'
+        queue_len = msg
+        msg = 'Submitted to grader. (Queue length: %s)' % queue_len 
+
+    context = { 'id': eid, 'state': status, 'msg': msg, 'value': value, 
+                'queued': queued, 'queue_len': queue_len
+              }
     html = render_template("filesubmission.html", context)
     return etree.XML(html) 
 
@@ -329,10 +340,18 @@ def textbox(element, value, status, render_template, msg=''):
     hidden = element.get('hidden', '')	 # if specified, then textline is hidden and id is stored in div of name given by hidden
 
     if not value: value = element.text	 # if no student input yet, then use the default input given by the problem
+    
+    # Check if problem has been queued
+    queued = '' 
+    queue_len = 0
+    if status == 'incomplete': # Flag indicating that the problem has been queued, 'msg' is length of queue
+        queued = 'true'
+        queue_len = msg
+        msg = 'Submitted to grader. (Queue length: %s)' % queue_len 
 
     # For CodeMirror
-    mode = element.get('mode')	or 'python' # mode, eg "python" or "xml"
-    linenumbers = element.get('linenumbers','true')	 # for CodeMirror
+    mode = element.get('mode','python') 
+    linenumbers = element.get('linenumbers','true')
     tabsize = element.get('tabsize','4')
     tabsize = int(tabsize)
 
@@ -340,6 +359,7 @@ def textbox(element, value, status, render_template, msg=''):
                'mode': mode, 'linenumbers': linenumbers,
                'rows': rows, 'cols': cols,
                'hidden': hidden, 'tabsize': tabsize,
+               'queued': queued, 'queue_len': queue_len,
                }
     html = render_template("textbox.html", context)
     try:

common/lib/capa/capa/responsetypes.py

@@ -898,7 +898,7 @@ class CodeResponse(LoncapaResponse):
                     'processor': self.code,
                     }
         
-        # Submit request
+        # Submit request. When successful, 'msg' is the prior length of the queue
         if is_file(submission):
             contents.update({'edX_student_response': submission.name})
             (error, msg) = qinterface.send_to_queue(header=xheader,
@@ -914,8 +914,11 @@ class CodeResponse(LoncapaResponse):
             cmap.set(self.answer_id, queuekey=None,
                      msg='Unable to deliver your submission to grader. (Reason: %s.) Please try again later.' % msg)
         else:
-            # Non-null CorrectMap['queuekey'] indicates that the problem has been queued 
-            cmap.set(self.answer_id, queuekey=queuekey, msg='Submitted to grader. (Queue length: %s)' % msg)
+            # Queueing mechanism flags:
+            #   1) Backend: Non-null CorrectMap['queuekey'] indicates that the problem has been queued
+            #   2) Frontend: correctness='incomplete' eventually trickles down through inputtypes.textbox 
+            #       and .filesubmission to inform the browser to poll the LMS
+            cmap.set(self.answer_id, queuekey=queuekey, correctness='incomplete', msg=msg)
 
         return cmap
 

common/lib/capa/capa/templates/filesubmission.html

@@ -9,6 +9,9 @@
     % elif state == 'incomplete':
     <span class="incorrect" id="status_${id}"></span>
     % endif
+    % if queued:
+    <span class="xqueue" id="${id}" >${queue_len}</span>
+    % endif
     <span class="debug">(${state})</span>
     <br/>
     <span class="message">${msg|n}</span>

common/lib/capa/capa/templates/textbox.html

@@ -19,6 +19,9 @@
   % if hidden:
       <div style="display:none;" name="${hidden}" inputid="input_${id}" />
   % endif
+  % if queued:
+    <span class="xqueue" id="${id}" >${queue_len}</span>
+  % endif
   <br/>
   <span class="debug">(${state})</span>
   <br/>

common/lib/capa/capa/xqueue_interface.py

@@ -10,7 +10,8 @@ import time
 # TODO: Collection of parameters to be hooked into rest of edX system
 XQUEUE_LMS_AUTH = { 'username': 'LMS',
                     'password': 'PaloAltoCA' }
-XQUEUE_URL = 'http://xqueue.edx.org'
+#XQUEUE_URL = 'http://xqueue.edx.org'
+XQUEUE_URL = 'http://ec2-50-17-47-60.compute-1.amazonaws.com'
 
 log = logging.getLogger('mitx.' + __name__)
 

common/lib/xmodule/xmodule/js/src/capa/display.coffee

@@ -4,6 +4,12 @@ class @Problem
     @id = @el.data('problem-id')
     @element_id = @el.attr('id')
     @url = @el.data('url')
+
+    # Destroy any existing polling threads on Problem change
+    if window.queuePollerID
+      window.clearTimeout(window.queuePollerID)
+      delete window.queuePollerID
+
     @render()
 
   $: (selector) ->
@@ -12,7 +18,10 @@ class @Problem
   bind: =>
     MathJax.Hub.Queue ["Typeset", MathJax.Hub]
     window.update_schematics()
-    @inputs = @$("[id^=input_#{@element_id.replace(/problem_/, '')}_]")
+
+    problem_prefix = @element_id.replace(/problem_/,'')
+    @inputs = @$("[id^=input_#{problem_prefix}_]")
+    
     @$('section.action input:button').click @refreshAnswers
     @$('section.action input.check').click @check_fd
     #@$('section.action input.check').click @check
@@ -26,15 +35,37 @@ class @Problem
         @el.attr progress: response.progress_status
         @el.trigger('progressChanged')
 
+  queueing: =>
+    @queued_items = @$(".xqueue")
+    if @queued_items.length > 0
+      if window.queuePollerID # Only one poller 'thread' per Problem
+        window.clearTimeout(window.queuePollerID)
+      window.queuePollerID = window.setTimeout(@poll, 100)
+
+  poll: =>
+    $.postWithPrefix "#{@url}/problem_get", (response) =>
+      @el.html(response.html)
+      @executeProblemScripts()
+      @bind()
+
+      @queued_items = @$(".xqueue")
+      if @queued_items.length == 0 
+        delete window.queuePollerID
+      else
+        # TODO: Dynamically adjust timeout interval based on @queued_items.value
+        window.queuePollerID = window.setTimeout(@poll, 1000)
+
   render: (content) ->
     if content
       @el.html(content)
       @bind()
+      @queueing()
     else
       $.postWithPrefix "#{@url}/problem_get", (response) =>
         @el.html(response.html)
         @executeProblemScripts()
         @bind()
+        @queueing()
 
   executeProblemScripts: ->
     @el.find(".script_placeholder").each (index, placeholder) ->