ENH: Command to load questions from XML file.

Added manage command to load questions from XML file.  Updated README
and including a simple set of sample questions for testing.

3 files changed, 64 insertions, 0 deletions

diff --git a/exam/management/__init__.py b/exam/management/__init__.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/exam/management/__init__.py
diff --git a/exam/management/commands/__init__.py b/exam/management/commands/__init__.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/exam/management/commands/__init__.py
diff --git a/exam/management/commands/load_questions.py b/exam/management/commands/load_questions.py
new file mode 100644
index 0000000..336ed92
--- /dev/null
+++ b/exam/management/commands/load_questions.py
@@ -0,0 +1,64 @@
+# System library imports.
+from os.path import basename
+from xml.dom.minidom import parse
+from htmlentitydefs import name2codepoint
+import re
+
+# Django imports.
+from django.core.management.base import BaseCommand
+
+# Local imports.
+from exam.models import Question
+
+def decode_html(html_str):
+    """Un-escape or decode HTML strings to more usable Python strings.
+    From here: http://wiki.python.org/moin/EscapingHtml
+    """
+    return re.sub('&(%s);' % '|'.join(name2codepoint), 
+            lambda m: unichr(name2codepoint[m.group(1)]), html_str)
+
+def clear_questions():
+    """Delete all questions from the database."""
+    for question in Question.objects.all():
+        question.delete()
+
+def load_questions(filename):
+    """Load questions from the given XML file."""
+    q_bank = parse(filename).getElementsByTagName("question")
+
+    for question in q_bank:
+
+        summary_node = question.getElementsByTagName("summary")[0]
+        summary = (summary_node.childNodes[0].data).strip()
+
+        desc_node = question.getElementsByTagName("description")[0]
+        description = (desc_node.childNodes[0].data).strip()
+
+        points_node = question.getElementsByTagName("points")[0]
+        points = int((points_node.childNodes[0].data).strip()) \
+                 if points_node else 1
+
+        test_node = question.getElementsByTagName("test")[0]
+        test = decode_html((test_node.childNodes[0].data).strip())
+
+        new_question = Question(summary=summary,
+                                description=description,
+                                points=points,
+                                test=test)
+        new_question.save()
+    
+class Command(BaseCommand):
+    args = '<q_file1.xml q_file2.xml>'
+    help = 'loads the questions from given XML files'
+    
+    def handle(self, *args, **options):
+        """Handle the command."""
+        # Delete existing stuff.
+        clear_questions()
+        
+        # Load from files.
+        for fname in args:
+            self.stdout.write('Importing from {0} ... '.format(basename(fname)))
+            load_questions(fname)
+            self.stdout.write('Done\n')
+