Refactor test setup for XBlock rendering and handlers.

apps/openassessment/xblock/test/base.py

+"""
+Base class for handler-level testing of the XBlock.
+"""
+import os.path
+import json
+from functools import wraps
+
+from django.test import TestCase
+from workbench.runtime import WorkbenchRuntime
+import webob
+
+
+def scenario(scenario_path, user_id=None):
+    """
+    Method decorator to load a scenario for a test case.
+    Must be called on an `XBlockHandlerTestCase` subclass, or
+    else it will have no effect.
+
+    Args:
+        scenario_path (str): Path to the scenario XML file.
+
+    Kwargs:
+        user_id (str or None): User ID to log in as, or None.
+
+    Returns:
+        The decorated method
+
+    Example:
+
+        @scenario('data/test_scenario.xml')
+        def test_submit(self, xblock):
+            response = self.request(xblock, 'submit', 'Test submission')
+            self.assertTrue('Success' in response)
+    """
+    def _decorator(func):
+        @wraps(func)
+        def _wrapped(*args, **kwargs):
+
+            # Retrieve the object (self)
+            # if this is a function, not a method, then do nothing.
+            xblock = None
+            if args:
+                self = args[0]
+                if isinstance(self, XBlockHandlerTestCase):
+
+                    # Configure the runtime with our user id
+                    self.set_user(user_id)
+
+                    # Load the scenario
+                    xblock = self.load_scenario(scenario_path)
+
+                    # Pass the XBlock as the first argument to the decorated method (after `self`)
+                    args = list(args)
+                    args.insert(1, xblock)
+
+            return func(*args, **kwargs)
+        return _wrapped
+    return _decorator
+
+
+class XBlockHandlerTestCase(TestCase):
+    """
+    Load the XBlock in the workbench runtime to test its handler.
+    """
+
+    def setUp(self):
+        """
+        Create the runtime.
+        """
+        self.runtime = WorkbenchRuntime()
+
+    def set_user(self, user_id):
+        """
+        Provide a user ID to the runtime.
+
+        Args:
+            user_id (str): a user ID.
+
+        Returns:
+            None
+        """
+        self.runtime.user_id = user_id
+
+    def load_scenario(self, xml_path):
+        """
+        Load an XML definition of an XBlock and return the XBlock instance.
+
+        Args:
+            xml (string): Path to an XML definition of the XBlock, relative
+                to the test module.
+
+        Returns:
+            XBlock
+        """
+        base_dir = os.path.dirname(os.path.abspath(__file__))
+        with open(os.path.join(base_dir, xml_path)) as xml_file:
+            block_id = self.runtime.parse_xml_string(
+                xml_file.read(), self.runtime.id_generator
+            )
+            return self.runtime.get_block(block_id)
+
+    def request(self, xblock, handler_name, content, response_format=None):
+        """
+        Make a request to an XBlock handler.
+
+        Args:
+            xblock (XBlock): The XBlock instance that should handle the request.
+            handler_name (str): The name of the handler.
+            content (unicode): Content of the request.
+
+        Kwargs:
+            response_format (None or str): Expected format of the response string.
+                If `None`, return the raw response content; if 'json', parse the
+                response as JSON and return the result.
+
+        Raises:
+            NotImplementedError: Response format not supported.
+
+        Returns:
+            Content of the response (mixed).
+        """
+        # Create a fake request
+        request = webob.Request(dict())
+        request.body = content
+
+        # Send the request to the XBlock handler
+        response = self.runtime.handle(xblock, handler_name, request)
+
+        # Parse the response (if a format is specified)
+        if response_format is None:
+            return response.body
+        elif response_format == 'json':
+            return json.loads(response.body)
+        else:
+            raise NotImplementedError("Response format '{format}' not supported".format(response_format))

apps/openassessment/xblock/test/data/basic_scenario.xml

+<openassessment start="2014-12-19T23:00:00" due="2014-12-21T23:00:00">
+    <prompt>
+        Given the state of the world today, what do you think should be done to
+        combat poverty? Please answer in a short essay of 200-300 words.
+    </prompt>
+    <rubric>
+        Read for conciseness, clarity of thought, and form.
+        <criterion name="concise">
+            How concise is it?
+            <option val="0">Neal Stephenson (late)</option>
+            <option val="1">HP Lovecraft</option>
+            <option val="3">Robert Heinlein</option>
+            <option val="4">Neal Stephenson (early)</option>
+            <option val="5">Earnest Hemingway</option>
+        </criterion>
+        <criterion name="clearheaded">
+            How clear is the thinking?
+            <option val="0">Yogi Berra</option>
+            <option val="1">Hunter S. Thompson</option>
+            <option val="2">Robert Heinlein</option>
+            <option val="3">Isaac Asimov</option>
+            <option val="10">Spock</option>
+        </criterion>
+        <criterion name="form">
+            Lastly, how is it's form? Punctuation, grammar, and spelling all count.
+            <option val="0">lolcats</option>
+            <option val="1">Facebook</option>
+            <option val="2">Reddit</option>
+            <option val="3">metafilter</option>
+            <option val="4">Usenet, 1996</option>
+            <option val="5">The Elements of Style</option>
+        </criterion>
+    </rubric>
+    <assessments>
+        <peer-assessment name="peer-assessment"
+          start="2014-12-20T19:00"
+          due="2014-12-21T22:22"
+          must_grade="5"
+          must_be_graded_by="3" />
+        <self-assessment name="self-assessment"/>
+    </assessments>
+</openassessment>