Semi-generic registration mechanism for modules. Still need to clean up…

Semi-generic registration mechanism for modules. Still need to clean up references in content_parser

--HG--
branch : pmitros-mod-template

courseware/module_render.py

@@ -26,28 +26,10 @@ import track.views
 
 import courseware.content_parser as content_parser
 
-import courseware.modules.capa_module
-import courseware.modules.html_module
-import courseware.modules.schematic_module
-import courseware.modules.seq_module
-import courseware.modules.template_module
-import courseware.modules.vertical_module
-import courseware.modules.video_module
+import courseware.modules
 
 log = logging.getLogger("mitx.courseware")
 
-## TODO: Add registration mechanism
-modx_modules={'problem':courseware.modules.capa_module.LoncapaModule, 
-              'video':courseware.modules.video_module.VideoModule,
-              'html':courseware.modules.html_module.HtmlModule,
-              'vertical':courseware.modules.vertical_module.VerticalModule,
-              'sequential':courseware.modules.seq_module.SequentialModule,
-              'tab':courseware.modules.seq_module.SequentialModule,
-              'schematic':courseware.modules.schematic_module.SchematicModule}
-
-for f in os.listdir(settings.DATA_DIR+'/custom_tags'):
-    modx_modules[f] = courseware.modules.template_module.TemplateModule
-
 def object_cache(cache, user, module_type, module_id):
     # We don't look up on user -- all queries include user
     # Additional lookup would require a DB hit the way Django 
@@ -78,18 +60,18 @@ def modx_dispatch(request, module=None, dispatch=None, id=None):
 
     ajax_url = '/modx/'+module+'/'+id+'/'
 
-    id_tag=modx_modules[module].id_attribute
+    id_tag=courseware.modules.get_module_class(module.id_attribute)
 
     # Grab the XML corresponding to the request from course.xml
     xml = content_parser.module_xml(content_parser.course_file(request.user), module, id_tag, id)
 
     # Create the module
-    instance=modx_modules[module](xml, 
-                                  s.module_id, 
-                                  ajax_url=ajax_url, 
-                                  state=s.state, 
-                                  track_function = make_track_function(request), 
-                                  render_function = None)
+    instance=courseware.modules.get_module_class(module)(xml, 
+                                                         s.module_id, 
+                                                         ajax_url=ajax_url, 
+                                                         state=s.state, 
+                                                         track_function = make_track_function(request), 
+                                                         render_function = None)
     # Let the module handle the AJAX
     ajax_return=instance.handle_ajax(dispatch, request.POST)
     # Save the state back to the database
@@ -104,7 +86,7 @@ def render_x_module(user, request, xml_module, module_object_preload):
     ''' Generic module for extensions. This renders to HTML. '''
     # Check if problem has an instance in DB
     module_type=xml_module.tag
-    module_class=modx_modules[module_type]
+    module_class=courseware.modules.get_module_class(module_type)
     module_id=xml_module.get('id') #module_class.id_attribute) or "" 
 
     # Grab state from database

courseware/modules/__init__.py

+import os
+import os.path
+
+from django.conf import settings
+
+import capa_module
+import html_module
+import schematic_module
+import seq_module
+import template_module
+import vertical_module
+import video_module
+
+# Import all files in modules directory, excluding backups (# and . in name) 
+# and __init__
+#
+# Stick them in a list
+modx_module_list = []
+
+for f in os.listdir(os.path.dirname(__file__)):
+    if f!='__init__.py' and \
+            f[-3:] == ".py" and \
+            "." not in f[:-3] \
+            and '#' not in f:
+        mod_path = 'courseware.modules.'+f[:-3]
+        mod = __import__(mod_path, fromlist = "courseware.modules")
+        if 'Module' in mod.__dict__:
+            modx_module_list.append(mod)
+
+# Convert list to a dictionary for lookup by tag
+modx_modules = {}
+for module in modx_module_list:
+    for tag in module.Module.get_xml_tags():
+        modx_modules[tag] = module.Module
+
+def get_module_class(tag):
+    return modx_modules[tag]
+

courseware/modules/capa_module.py

@@ -26,15 +26,18 @@ import courseware.content_parser as content_parser
 
 log = logging.getLogger("mitx.courseware")
 
-class LoncapaModule(XModule):
+class Module(XModule):
     ''' Interface between capa_problem and x_module. Originally a hack
     meant to be refactored out, but it seems to be serving a useful
     prupose now. We can e.g .destroy and create the capa_problem on a
     reset. 
     '''
-    xml_tags = ["problem"]
+
     id_attribute = "filename"
 
+    @classmethod
+    def get_xml_tags(c):
+        return ["problem"]
 
     def get_state(self):
         state = self.lcp.get_state()

courseware/modules/html_module.py

@@ -7,14 +7,15 @@ from mitxmako.shortcuts import render_to_response, render_to_string
 from x_module import XModule
 from lxml import etree
 
-class HtmlModule(XModule):
+class Module(XModule):
     id_attribute = 'filename'
 
     def get_state(self):
         return json.dumps({ })
 
-    def get_xml_tags():
-        return "html"
+    @classmethod
+    def get_xml_tags(c):
+        return ["html"]
         
     def get_html(self):
         if self.filename==None:

courseware/modules/schematic_module.py

@@ -6,14 +6,15 @@ from mitxmako.shortcuts import render_to_response, render_to_string
 
 from x_module import XModule
 
-class SchematicModule(XModule):
+class Module(XModule):
     id_attribute = 'id'
 
     def get_state(self):
         return json.dumps({ })
 
-    def get_xml_tags():
-        return "schematic"
+    @classmethod
+    def get_xml_tags(c):
+        return ["schematic"]
         
     def get_html(self):
         return '<input type="hidden" class="schematic" name="{item_id}" height="480" width="640">'.format(item_id=self.item_id)

courseware/modules/seq_module.py

@@ -13,7 +13,7 @@ from x_module import XModule
 # OBSOLETE: This obsoletes 'type'
 class_priority = ['video', 'problem']
 
-class SequentialModule(XModule):
+class Module(XModule):
     ''' Layout module which lays out content in a temporal sequence
     '''
     id_attribute = 'id'
@@ -21,7 +21,8 @@ class SequentialModule(XModule):
     def get_state(self):
         return json.dumps({ 'position':self.position })
 
-    def get_xml_tags():
+    @classmethod
+    def get_xml_tags(c):
         return ["sequential", 'tab']
         
     def get_html(self):

courseware/modules/vertical_module.py

@@ -7,14 +7,15 @@ from mitxmako.shortcuts import render_to_response, render_to_string
 from x_module import XModule
 from lxml import etree
 
-class VerticalModule(XModule):
+class Module(XModule):
     id_attribute = 'id'
 
     def get_state(self):
         return json.dumps({ })
 
-    def get_xml_tags():
-        return "vertical"
+    @classmethod
+    def get_xml_tags(c):
+        return ["vertical"]
         
     def get_html(self):
         return render_to_string('vert_module.html',{'items':self.contents})

courseware/modules/video_module.py

@@ -11,7 +11,7 @@ from x_module import XModule
 
 log = logging.getLogger("mitx.courseware.modules")
 
-class VideoModule(XModule):
+class Module(XModule):
     #id_attribute = 'youtube'
     video_time = 0
 
@@ -28,9 +28,10 @@ class VideoModule(XModule):
         log.debug(u"STATE POSITION {0}".format(self.position))
         return json.dumps({ 'position':self.position })
 
-    def get_xml_tags():
+    @classmethod
+    def get_xml_tags(c):
         '''Tags in the courseware file guaranteed to correspond to the module'''
-        return "video"
+        return ["video"]
         
     def video_list(self):
         l = self.youtube.split(',')

courseware/modules/x_module.py

@@ -10,7 +10,8 @@ class XModule(object):
     '''
     id_attribute='name' # An attribute guaranteed to be unique
 
-    def get_xml_tags():
+    @classmethod
+    def get_xml_tags(c):
         ''' Tags in the courseware file guaranteed to correspond to the module '''
         return []