Add timestamp and wait for 35 sec.

CHANGELOG.rst

@@ -5,6 +5,9 @@ These are notable changes in edx-platform.  This is a rolling list of changes,
 in roughly chronological order, most recent first.  Add your entries at or near
 the top.  Include a label indicating the component affected.
 
+Blades: Handle situation if no response were sent from XQueue to LMS in Matlab
+problem after Run Code button press. BLD-994.
+
 Blades: Set initial video quality to large instead of default to avoid automatic switch to HD when iframe resizes. BLD-981.
 
 Blades: Add an upload button for authors to provide students with an option to

common/lib/capa/capa/inputtypes.py

@@ -39,6 +39,7 @@ graded status as'status'
 # makes sense, but a bunch of problems have markup that assumes block.  Bigger TODO: figure out a
 # general css and layout strategy for capa, document it, then implement it.
 
+import time
 import json
 import logging
 from lxml import etree
@@ -53,6 +54,7 @@ from .registry import TagRegistry
 from chem import chemcalc
 from calc.preview import latex_preview
 import xqueue_interface
+from xqueue_interface import XQUEUE_TIMEOUT
 from datetime import datetime
 from xmodule.stringify import stringify_children
 
@@ -821,6 +823,15 @@ class MatlabInput(CodeInput):
             self.status = 'queued'
             self.queue_len = 1
             self.msg = self.submitted_msg
+            # Handle situation if no response from xqueue arrived during specified time.
+            if ('queuetime' not in self.input_state or
+                    time.time() - self.input_state['queuetime'] > XQUEUE_TIMEOUT):
+                self.queue_len = 0
+                self.status = 'unsubmitted'
+                self.msg = _(
+                    'No response from Xqueue within {xqueue_timeout} seconds. Aborted.'
+                ).format(xqueue_timeout=XQUEUE_TIMEOUT)
+
 
     def handle_ajax(self, dispatch, data):
         """
@@ -945,6 +956,7 @@ class MatlabInput(CodeInput):
         if error == 0:
             self.input_state['queuekey'] = queuekey
             self.input_state['queuestate'] = 'queued'
+            self.input_state['queuetime'] = time.time()
 
         return {'success': error == 0, 'message': msg}
 

common/lib/capa/capa/tests/test_inputtypes.py

@@ -28,6 +28,8 @@ from capa import inputtypes
 from mock import ANY, patch
 from pyparsing import ParseException
 
+from capa.xqueue_interface import XQUEUE_TIMEOUT
+
 # just a handy shortcut
 lookup_tag = inputtypes.registry.get_class_for_tag
 
@@ -524,10 +526,11 @@ class MatlabTest(unittest.TestCase):
 
             self.assertEqual(context, expected)
 
-    def test_rendering_while_queued(self):
+    @patch('capa.inputtypes.time.time', return_value=10)
+    def test_rendering_while_queued(self, time):
         state = {'value': 'print "good evening"',
                  'status': 'incomplete',
-                 'input_state': {'queuestate': 'queued'},
+                 'input_state': {'queuestate': 'queued', 'queuetime': 5},
                  }
         elt = etree.fromstring(self.xml)
 
@@ -576,9 +579,10 @@ class MatlabTest(unittest.TestCase):
         self.assertTrue('queuekey' not in self.the_input.input_state)
         self.assertTrue('queuestate' not in self.the_input.input_state)
 
-    def test_ungraded_response_success(self):
+    @patch('capa.inputtypes.time.time', return_value=10)
+    def test_ungraded_response_success(self, time):
         queuekey = 'abcd'
-        input_state = {'queuekey': queuekey, 'queuestate': 'queued'}
+        input_state = {'queuekey': queuekey, 'queuestate': 'queued', 'queuetime': 5}
         state = {'value': 'print "good evening"',
                  'status': 'incomplete',
                  'input_state': input_state,
@@ -594,9 +598,10 @@ class MatlabTest(unittest.TestCase):
         self.assertTrue(input_state['queuestate'] is None)
         self.assertEqual(input_state['queue_msg'], inner_msg)
 
-    def test_ungraded_response_key_mismatch(self):
+    @patch('capa.inputtypes.time.time', return_value=10)
+    def test_ungraded_response_key_mismatch(self, time):
         queuekey = 'abcd'
-        input_state = {'queuekey': queuekey, 'queuestate': 'queued'}
+        input_state = {'queuekey': queuekey, 'queuestate': 'queued', 'queuetime': 5}
         state = {'value': 'print "good evening"',
                  'status': 'incomplete',
                  'input_state': input_state,
@@ -612,6 +617,41 @@ class MatlabTest(unittest.TestCase):
         self.assertEqual(input_state['queuestate'], 'queued')
         self.assertFalse('queue_msg' in input_state)
 
+    @patch('capa.inputtypes.time.time', return_value=20)
+    def test_matlab_response_timeout_not_exceeded(self, time):
+
+        state = {'input_state': {'queuestate': 'queued', 'queuetime': 5}}
+        elt = etree.fromstring(self.xml)
+
+        the_input = self.input_class(test_capa_system(), elt, state)
+        context = the_input._get_render_context()
+        self.assertEqual(the_input.status, 'queued')
+
+
+    @patch('capa.inputtypes.time.time', return_value=45)
+    def test_matlab_response_timeout_exceeded(self, time):
+
+        state = {'input_state': {'queuestate': 'queued', 'queuetime': 5}}
+        elt = etree.fromstring(self.xml)
+
+        the_input = self.input_class(test_capa_system(), elt, state)
+        context = the_input._get_render_context()
+        self.assertEqual(the_input.status, 'unsubmitted')
+        self.assertEqual(the_input.msg, 'No response from Xqueue within {} seconds. Aborted.'.format(XQUEUE_TIMEOUT))
+
+    @patch('capa.inputtypes.time.time', return_value=20)
+    def test_matlab_response_migration_of_queuetime(self, time):
+        """
+        Test if problem was saved before queuetime was introduced.
+        """
+        state = {'input_state': {'queuestate': 'queued'}}
+        elt = etree.fromstring(self.xml)
+
+        the_input = self.input_class(test_capa_system(), elt, state)
+        context = the_input._get_render_context()
+        self.assertEqual(the_input.status, 'unsubmitted')
+
+
     def test_get_html(self):
         # usual output
         output = self.the_input.get_html()
@@ -693,7 +733,7 @@ class MatlabTest(unittest.TestCase):
         the_input = self.input_class(test_capa_system(), elt, state)
         context = the_input._get_render_context()  # pylint: disable=W0212
         self.maxDiff = None
-        expected = u'\n<div class="matlabResponse"><div class="commandWindowOutput" style="white-space: pre;"> <strong>if</strong> Conditionally execute statements.\nThe general form of the <strong>if</strong> statement is\n\n   <strong>if</strong> expression\n     statements\n   ELSEIF expression\n     statements\n   ELSE\n     statements\n   END\n\nThe statements are executed if the real part of the expression \nhas all non-zero elements. The ELSE and ELSEIF parts are optional.\nZero or more ELSEIF parts can be used as well as nested <strong>if</strong>\'s.\nThe expression is usually of the form expr rop expr where \nrop is ==, &lt;, &gt;, &lt;=, &gt;=, or ~=.\n<img src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAjAAAAGkCAIAAACgj==">\n\nExample\n   if I == J\n     A(I,J) = 2;\n   elseif abs(I-J) == 1\n     A(I,J) = -1;\n   else\n     A(I,J) = 0;\n   end\n\nSee also <a>relop</a>, <a>else</a>, <a>elseif</a>, <a>end</a>, <a>for</a>, <a>while</a>, <a>switch</a>.\n\nReference page in Help browser\n   <a>doc if</a>\n\n</div><ul></ul></div>\n'
+        expected = u'\n<div class="matlabResponse"><div class="commandWindowOutput" style="white-space: pre;"> <strong>if</strong> Conditionally execute statements.\nThe general form of the <strong>if</strong> statement is\n\n   <strong>if</strong> expression\n     statements\n   ELSEIF expression\n     statements\n   ELSE\n     statements\n   END\n\nThe statements are executed if the real part of the expression\nhas all non-zero elements. The ELSE and ELSEIF parts are optional.\nZero or more ELSEIF parts can be used as well as nested <strong>if</strong>\'s.\nThe expression is usually of the form expr rop expr where\nrop is ==, &lt;, &gt;, &lt;=, &gt;=, or ~=.\n<img src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAjAAAAGkCAIAAACgj==">\n\nExample\n   if I == J\n     A(I,J) = 2;\n   elseif abs(I-J) == 1\n     A(I,J) = -1;\n   else\n     A(I,J) = 0;\n   end\n\nSee also <a>relop</a>, <a>else</a>, <a>elseif</a>, <a>end</a>, <a>for</a>, <a>while</a>, <a>switch</a>.\n\nReference page in Help browser\n   <a>doc if</a>\n\n</div><ul></ul></div>\n'
 
         self.assertEqual(context['queue_msg'], expected)
 

common/lib/capa/capa/xqueue_interface.py

@@ -13,6 +13,9 @@ dateformat = '%Y%m%d%H%M%S'
 
 XQUEUE_METRIC_NAME = 'edxapp.xqueue'
 
+# Wait time for response from Xqueue.
+XQUEUE_TIMEOUT = 35 # seconds
+
 
 def make_hashkey(seed):
     """