Parse and serialize multiple prompts

TNL-708

openassessment/xblock/openassessmentblock.py

@@ -418,7 +418,7 @@ class OpenAssessmentBlock(
 
         xblock_validator = validator(block, block._, strict_post_release=False)
         xblock_validator(
-            create_rubric_dict(config['prompt'], config['rubric_criteria']),
+            create_rubric_dict(config['prompts'], config['rubric_criteria']),
             config['rubric_assessments'],
             submission_start=config['submission_start'],
             submission_due=config['submission_due'],
@@ -432,7 +432,7 @@ class OpenAssessmentBlock(
         block.submission_start = config['submission_start']
         block.submission_due = config['submission_due']
         block.title = config['title']
-        block.prompt = config['prompt']
+        block.prompts = config['prompts']
         block.allow_file_upload = config['allow_file_upload']
         block.allow_latex = config['allow_latex']
         block.leaderboard_show = config['leaderboard_show']

openassessment/xblock/xml.py

@@ -55,6 +55,26 @@ def _safe_get_text(element):
     return unicode(element.text) if element.text is not None else u""
 
 
+def _serialize_prompts(prompts_root, prompts_list):
+    """
+    Serialize prompts as XML, adding children to the XML with root
+    node `prompts_root`.
+
+    Args:
+        prompts_root (lxml.etree.Element): The root node of the tree.
+        prompts_list (list): List of prompt dictionaries.
+
+    Returns:
+        None
+    """
+    for prompt in prompts_list:
+        prompt_el = etree.SubElement(prompts_root, 'prompt')
+
+        # Prompt description
+        prompt_description = etree.SubElement(prompt_el, 'description')
+        prompt_description.text = unicode(prompt.get('description', u''))
+
+
 def _serialize_options(options_root, options_list):
     """
     Serialize rubric criterion options as XML, adding children to the XML
@@ -139,7 +159,7 @@ def _serialize_criteria(criteria_root, criteria_list):
             _serialize_options(criterion_el, options_list)
 
 
-def serialize_rubric(rubric_root, oa_block, include_prompt=True):
+def serialize_rubric(rubric_root, oa_block):
     """
     Serialize a rubric dictionary as XML, adding children to the XML
     with root node `rubric_root`.
@@ -153,17 +173,9 @@ def serialize_rubric(rubric_root, oa_block, include_prompt=True):
         rubric_dict (dict): A dictionary representation of the rubric, of the form
             described in the serialized Rubric model (peer grading serializers).
 
-    Kwargs:
-        include_prompt (bool): Whether or not to include the prompt in the
-            serialized format for a rubric. Defaults to True.
     Returns:
         None
     """
-    # Rubric prompt (default to empty text); None indicates no input element
-    if include_prompt and oa_block.prompt is not None:
-        prompt = etree.SubElement(rubric_root, 'prompt')
-        prompt.text = unicode(oa_block.prompt)
-
     # Criteria
     criteria_list = oa_block.rubric_criteria
 
@@ -227,6 +239,51 @@ def _parse_boolean(boolean_str):
     return boolean_str in ['True', 'true']
 
 
+def _parse_prompts_xml(root):
+    """
+    Parse <prompts> element in the OpenAssessment XBlock's content XML.
+
+    Args:
+        root (lxml.etree.Element): The root node of the tree.
+
+    Returns:
+        list of prompts dictionaries.
+
+    Raises:
+        UpdateFromXmlError: The XML definition is invalid or the XBlock could not be updated.
+    """
+    prompts_list = []
+
+    prompts_el = root.find('prompts')
+    if prompts_el is not None:
+        for prompt in prompts_el.findall('prompt'):
+            prompt_dict = dict()
+
+            # Prompt description
+            prompt_description = prompt.find('description')
+            if prompt_description is not None:
+                prompt_dict['description'] = _safe_get_text(prompt_description)
+            else:
+                raise UpdateFromXmlError('Every "prompt" element must contain a "description" element.')
+
+            prompts_list.append(prompt_dict)
+    else:
+        # For backwards compatibility. Initially a single prompt element was added in
+        # the rubric element.
+        rubric_el = root.find('rubric')
+        prompt_el = rubric_el.find('prompt')
+        prompt_description = ''
+        if prompt_el is not None:
+            prompt_description = _safe_get_text(prompt_el)
+
+        prompts_list.append(
+            {
+                'description': prompt_description,
+            }
+        )
+
+    return prompts_list
+
 def _parse_options_xml(options_root):
     """
     Parse <options> element in the OpenAssessment XBlock's content XML.
@@ -368,13 +425,6 @@ def parse_rubric_xml(rubric_root):
     """
     rubric_dict = dict()
 
-    # Rubric prompt
-    prompt_el = rubric_root.find('prompt')
-    if prompt_el is not None:
-        rubric_dict['prompt'] = _safe_get_text(prompt_el)
-    else:
-        rubric_dict['prompt'] = None
-
     feedback_prompt_el = rubric_root.find('feedbackprompt')
     if feedback_prompt_el is not None:
         rubric_dict['feedbackprompt'] = _safe_get_text(feedback_prompt_el)
@@ -635,6 +685,10 @@ def serialize_content_to_xml(oa_block, root):
     assessments_root = etree.SubElement(root, 'assessments')
     serialize_assessments(assessments_root, oa_block)
 
+    # Prompts
+    prompts_root = etree.SubElement(root, 'prompts')
+    _serialize_prompts(prompts_root, oa_block.prompts)
+
     # Rubric
     rubric_root = etree.SubElement(root, 'rubric')
     serialize_rubric(rubric_root, oa_block)
@@ -673,7 +727,7 @@ def serialize_rubric_to_xml_str(oa_block):
 
     """
     rubric_root = etree.Element('rubric')
-    serialize_rubric(rubric_root, oa_block, include_prompt=False)
+    serialize_rubric(rubric_root, oa_block)
     return etree.tostring(rubric_root, pretty_print=True, encoding='unicode')
 
 
@@ -767,6 +821,9 @@ def parse_from_xml(root):
     else:
         rubric = parse_rubric_xml(rubric_el)
 
+    # Retrieve the prompts
+    prompts = _parse_prompts_xml(root)
+
     # Retrieve the leaderboard if it exists, otherwise set it to 0
     leaderboard_show = 0
     if 'leaderboard_show' in root.attrib:
@@ -784,7 +841,7 @@ def parse_from_xml(root):
 
     return {
         'title': title,
-        'prompt': rubric['prompt'],
+        'prompts': prompts,
         'rubric_criteria': rubric['criteria'],
         'rubric_assessments': assessments,
         'rubric_feedback_prompt': rubric['feedbackprompt'],