Add resource loading utils

tests/unit/data/simple_django_template.txt

+This is a simple django template example.
+
+This template can make use of the following context variables:
+Name: {{name}}
+List: {{items|safe}}
+
+It can also do some fancy things with them:
+Default value if name is empty: {{name|default:"Default Name"}}
+Length of the list: {{items|length}}
+Items of the list:{% for item in items %} {{item}}{% endfor %}

tests/unit/test_resources.py

+import unittest
+
+from xblockutils.resources import ResourceLoader
+
+
+expected_string = u"""\
+This is a simple django template example.
+
+This template can make use of the following context variables:
+Name: {{name}}
+List: {{items|safe}}
+
+It can also do some fancy things with them:
+Default value if name is empty: {{name|default:"Default Name"}}
+Length of the list: {{items|length}}
+Items of the list:{% for item in items %} {{item}}{% endfor %}
+"""
+
+
+example_context = {
+    "name": "This is a fine name",
+    "items": [1, 2, 3, 4, "a", "b", "c"],
+}
+
+
+expected_filled_template = u"""\
+This is a simple django template example.
+
+This template can make use of the following context variables:
+Name: This is a fine name
+List: [1, 2, 3, 4, 'a', 'b', 'c']
+
+It can also do some fancy things with them:
+Default value if name is empty: This is a fine name
+Length of the list: 7
+Items of the list: 1 2 3 4 a b c
+"""
+
+example_id = "example-unique-id"
+
+expected_filled_js_template = u"""\
+<script type='text/template' id='example-unique-id'>
+{}
+</script>\
+""".format(expected_filled_template)
+
+
+class TestResourceLoader(unittest.TestCase):
+    def test_load_unicode(self):
+        s = ResourceLoader(__name__).load_unicode("data/simple_django_template.txt")
+        self.assertEquals(s, expected_string)
+
+    def test_load_unicode_from_another_module(self):
+        s = ResourceLoader("tests.unit.data").load_unicode("simple_django_template.txt")
+        self.assertEquals(s, expected_string)
+
+    def test_render_template(self):
+        loader = ResourceLoader("tests.unit.data")
+        s = loader.render_template("simple_django_template.txt", example_context)
+        self.assertEquals(s, expected_filled_template)
+
+    def test_render_js_template(self):
+        loader = ResourceLoader("tests.unit.data")
+        s = loader.render_js_template("simple_django_template.txt", example_id, example_context)
+        self.assertEquals(s, expected_filled_js_template)

xblockutils/resources.py

+import pkg_resources
+from django.template import Context, Template
+
+
+class ResourceLoader(object):
+    def __init__(self, module_name):
+        self.module_name = module_name
+
+    def load_unicode(self, resource_path):
+        """
+        Gets the content of a resource
+        """
+        resource_content = pkg_resources.resource_string(self.module_name, resource_path)
+        return unicode(resource_content)
+
+    def render_template(self, template_path, context={}):
+        """
+        Evaluate a template by resource path, applying the provided context
+        """
+        template_str = self.load_unicode(template_path)
+        template = Template(template_str)
+        return template.render(Context(context))
+
+    def render_js_template(self, template_path, element_id, context={}):
+        """
+        Render a js template.
+        """
+        return u"<script type='text/template' id='{}'>\n{}\n</script>".format(
+            element_id,
+            self.render_template(template_path, context)
+        )