Add initial set of views for managing cohorts

- lets user see and add cohorts
- needs styling
- needs to allow them to actually manage membership!

common/djangoapps/course_groups/models.py

+import logging
+
 from django.contrib.auth.models import User
 from django.db import models
 
+log = logging.getLogger(__name__)
+
 class CourseUserGroup(models.Model):
     """
     This model represents groups of users in a course.  Groups may have different types,
@@ -27,7 +31,6 @@ class CourseUserGroup(models.Model):
     GROUP_TYPE_CHOICES = ((COHORT, 'Cohort'),)
     group_type = models.CharField(max_length=20, choices=GROUP_TYPE_CHOICES)
 
-
 def get_cohort(user, course_id):
     """
     Given a django User and a course_id, return the user's cohort.  In classes with
@@ -65,3 +68,49 @@ def get_course_cohorts(course_id):
     """
     return list(CourseUserGroup.objects.filter(course_id=course_id,
                                                group_type=CourseUserGroup.COHORT))
+
+### Helpers for cohor management views
+
+def get_cohort_by_name(course_id, name):
+    """
+    Return the CourseUserGroup object for the given cohort.  Raises DoesNotExist
+    it isn't present.
+    """
+    return CourseUserGroup.objects.get(course_id=course_id,
+                                       group_type=CourseUserGroup.COHORT,
+                                       name=name)
+
+def add_cohort(course_id, name):
+    """
+    Add a cohort to a course.  Raises ValueError if a cohort of the same name already
+    exists.
+    """
+    log.debug("Adding cohort %s to %s", name, course_id)
+    if CourseUserGroup.objects.filter(course_id=course_id,
+                                      group_type=CourseUserGroup.COHORT,
+                                      name=name).exists():
+        raise ValueError("Can't create two cohorts with the same name")
+
+    return CourseUserGroup.objects.create(course_id=course_id,
+                                          group_type=CourseUserGroup.COHORT,
+                                          name=name)
+
+def get_course_cohort_names(course_id):
+    """
+    Return a list of the cohort names in a course.
+    """
+    return [c.name for c in get_course_cohorts(course_id)]
+
+
+def delete_empty_cohort(course_id, name):
+    """
+    Remove an empty cohort.  Raise ValueError if cohort is not empty.
+    """
+    cohort = get_cohort_by_name(course_id, name)
+    if cohort.users.exists():
+        raise ValueError(
+            "Can't delete non-empty cohort {0} in course {1}".format(
+                name, course_id))
+
+    cohort.delete()
+

common/djangoapps/course_groups/views.py

+import json
+from django_future.csrf import ensure_csrf_cookie
+from django.contrib.auth.decorators import login_required
+from django.core.context_processors import csrf
+from django.core.urlresolvers import reverse
+from django.http import HttpResponse, HttpResponseForbidden, Http404
+from django.shortcuts import redirect
+import logging
+
+from courseware.courses import get_course_with_access
+from mitxmako.shortcuts import render_to_response, render_to_string
+from .models import CourseUserGroup
+from . import models
+
+import track.views
+
+
+log = logging.getLogger(__name__)
+
+def JsonHttpReponse(data):
+    """
+    Return an HttpResponse with the data json-serialized and the right content type
+    header.  Named to look like a class.
+    """
+    return HttpResponse(json.dumps(data), content_type="application/json")
+
+@ensure_csrf_cookie
+def list_cohorts(request, course_id):
+    """
+    Return json dump of dict:
+
+    {'success': True,
+     'cohorts': [{'name': name, 'id': id}, ...]}
+    """
+    get_course_with_access(request.user, course_id, 'staff')
+
+    cohorts = [{'name': c.name, 'id': c.id}
+               for c in models.get_course_cohorts(course_id)]
+
+    return JsonHttpReponse({'success': True,
+                            'cohorts': cohorts})
+
+
+@ensure_csrf_cookie
+def add_cohort(request, course_id):
+    """
+    Return json of dict:
+    {'success': True,
+     'cohort': {'id': id,
+                'name': name}}
+
+                or
+
+    {'success': False,
+     'msg': error_msg} if there's an error
+    """
+    get_course_with_access(request.user, course_id, 'staff')
+
+
+    if request.method != "POST":
+        raise Http404("Must POST to add cohorts")
+
+    name = request.POST.get("name")
+    if not name:
+        return JsonHttpReponse({'success': False,
+                                'msg': "No name specified"})
+
+    try:
+        cohort = models.add_cohort(course_id, name)
+    except ValueError as err:
+        return JsonHttpReponse({'success': False,
+                                'msg': str(err)})
+
+    return JsonHttpReponse({'success': 'True',
+                            'cohort': {
+                                'id': cohort.id,
+                                'name': cohort.name
+                                }})
+
+
+@ensure_csrf_cookie
+def users_in_cohort(request, course_id, cohort_id):
+    """
+    """
+    get_course_with_access(request.user, course_id, 'staff')
+
+    return JsonHttpReponse({'error': 'Not implemented'})
+
+
+@ensure_csrf_cookie
+def add_users_to_cohort(request, course_id):
+    """
+    """
+    get_course_with_access(request.user, course_id, 'staff')
+
+    return JsonHttpReponse({'error': 'Not implemented'})
+
+
+def debug_cohort_mgmt(request, course_id):
+    """
+    Debugging view for dev.
+    """
+    # add staff check to make sure it's safe if it's accidentally deployed.
+    get_course_with_access(request.user, course_id, 'staff')
+    
+    context = {'cohorts_ajax_url': reverse('cohorts',
+                                           kwargs={'course_id': course_id})}
+    return render_to_response('/course_groups/debug.html', context)

common/static/js/course_groups/cohorts.js

+// structure stolen from http://briancray.com/posts/javascript-module-pattern
+
+var CohortManager = (function ($) {
+    // private variables and functions
+
+    // using jQuery
+    function getCookie(name) {
+        var cookieValue = null;
+        if (document.cookie && document.cookie != '') {
+            var cookies = document.cookie.split(';');
+            for (var i = 0; i < cookies.length; i++) {
+                var cookie = $.trim(cookies[i]);
+                // Does this cookie string begin with the name we want?
+                if (cookie.substring(0, name.length + 1) == (name + '=')) {
+                    cookieValue = decodeURIComponent(cookie.substring(name.length + 1));
+                    break;
+                }
+            }
+        }
+        return cookieValue;
+    }
+    var csrftoken = getCookie('csrftoken');
+    
+    function csrfSafeMethod(method) {
+        // these HTTP methods do not require CSRF protection
+        return (/^(GET|HEAD|OPTIONS|TRACE)$/.test(method));
+    }  
+    $.ajaxSetup({
+        crossDomain: false, // obviates need for sameOrigin test
+        beforeSend: function(xhr, settings) {
+            if (!csrfSafeMethod(settings.type)) {
+                xhr.setRequestHeader("X-CSRFToken", csrftoken);
+            }
+        }
+    });
+
+    // constructor
+    var module = function () {
+        var url = $(".cohort_manager").data('ajax_url');
+        var self = this;
+        var error_list = $(".cohort_errors");
+        var cohort_list = $(".cohort_list");
+        var cohorts_display = $(".cohorts_display");
+        var show_cohorts_button = $(".cohort_controls .show_cohorts");
+        var add_cohort_input = $("#cohort-name");
+        var add_cohort_button = $(".add_cohort");
+
+        function show_cohort(item) {
+            // item is a li that has a data-href link to the cohort base url
+            var el = $(this);
+            alert("would show you data about " + el.text() + " from " + el.data('href'));
+        }
+
+        function add_to_cohorts_list(item) {
+            var li = $('<li><a></a></li>');
+            $("a", li).text(item.name)
+                .data('href', url + '/' + item.id)
+                .addClass('link')
+                .click(show_cohort);
+            cohort_list.append(li);
+        };
+
+        function log_error(msg) {
+            error_list.empty();
+            error_list.append($("<li />").text(msg).addClass("error"));
+        };
+        
+        function load_cohorts(response) {
+            cohort_list.empty();
+            if (response && response.success) { 
+                response.cohorts.forEach(add_to_cohorts_list);
+            } else {
+                log_error(response.msg || "There was an error loading cohorts");
+            }
+            cohorts_display.show();
+        };
+
+        function added_cohort(response) {
+            if (response && response.success) {
+                add_to_cohorts_list(response.cohort);
+            } else {
+                log_error(response.msg || "There was an error adding a cohort");
+            }                
+        }
+
+        show_cohorts_button.click(function() { 
+            $.ajax(url).done(load_cohorts);
+        });
+        
+        add_cohort_input.change(function() {
+            if (!$(this).val()) {
+                add_cohort_button.removeClass('button').addClass('button-disabled');
+            } else {
+                add_cohort_button.removeClass('button-disabled').addClass('button');
+            }
+        });
+
+        add_cohort_button.click(function() { 
+            var add_url = url + '/add';
+            data = {'name': add_cohort_input.val()}
+            $.post(add_url, data).done(added_cohort);
+        });
+
+    };
+
+    // prototype
+    module.prototype = {
+        constructor: module,
+    };
+
+    // return module
+    return module;
+})(jQuery);
+
+$(window).load(function () {
+    var my_module = new CohortManager();
+})
+

lms/djangoapps/instructor/views.py

@@ -562,6 +562,7 @@ def instructor_dashboard(request, course_id):
                'djangopid' : os.getpid(),
                'mitx_version' : getattr(settings,'MITX_VERSION_STRING',''),
                'offline_grade_log' : offline_grades_available(course_id),
+               'cohorts_ajax_url' : reverse('cohorts', kwargs={'course_id': course_id}),
                }
 
     return render_to_response('courseware/instructor_dashboard.html', context)

lms/templates/course_groups/cohort_management.html

+<section class="cohort_manager" data-ajax_url="${cohorts_ajax_url}">
+<h3>Cohort groups</h3>
+
+<div class="cohort_controls">
+  <a href="#" class="button show_cohorts">Show cohorts</a>
+</div>
+
+<ul class="cohort_errors">
+</ul>
+
+<div class="cohorts_display" style="display:none">
+  <h3>Cohorts in the course</h3>
+  <ul class="cohort_list">
+  </ul>
+
+  <p>
+  <input id="cohort-name"/>
+  <a href="#" class="button add_cohort">Add cohort</a>
+  </p>
+  
+
+</div>
+
+
+</section>

lms/templates/course_groups/debug.html

+<!DOCTYPE html>
+<html>
+<head>
+  <%block name="title"><title>edX</title></%block>
+
+  <script type="text/javascript" src="/static/js/vendor/jquery.min.js"></script>
+  <script type="text/javascript" src="/static/js/course_groups/cohorts.js"></script>
+
+</head>
+
+<body class="<%block name='bodyclass'/>">
+<%include file="/course_groups/cohort_management.html" />
+
+</body>
+</html>
+

lms/templates/courseware/instructor_dashboard.html

@@ -6,6 +6,8 @@
   <%static:css group='course'/>
   <script type="text/javascript" src="${static.url('js/vendor/flot/jquery.flot.js')}"></script>
   <script type="text/javascript" src="${static.url('js/vendor/flot/jquery.flot.axislabels.js')}"></script>
+  <script type="text/javascript" src="${static.url('js/course_groups/cohorts.js')}"></script>
+
 </%block>
 
 <%include file="/courseware/course_navigation.html" args="active_page='instructor'" />
@@ -282,16 +284,19 @@ function goto( mode)
     <input type="submit" name="action" value="Add beta testers">
     </p>
     <hr width="40%" style="align:left">
+
+    <%include file="/course_groups/cohort_management.html" />
+
   %endif
 %endif
 
     </form>
+##----------------------------------------------------------------------------- 
 
 %if msg:
     <p></p><p>${msg}</p>
 %endif
 ##----------------------------------------------------------------------------- 
-##----------------------------------------------------------------------------- 
 
 %if datatable and modeflag.get('Psychometrics') is None:
 

lms/urls.py

@@ -274,6 +274,23 @@ if settings.COURSEWARE_ENABLED:
             'open_ended_grading.peer_grading_service.save_grade', name='peer_grading_save_grade'),
         url(r'^courses/(?P<course_id>[^/]+/[^/]+/[^/]+)/peer_grading/save_calibration_essay$',
             'open_ended_grading.peer_grading_service.save_calibration_essay', name='peer_grading_save_calibration_essay'),
+
+        # Cohorts management
+        url(r'^courses/(?P<course_id>[^/]+/[^/]+/[^/]+)/cohorts$',
+            'course_groups.views.list_cohorts', name="cohorts"),
+        url(r'^courses/(?P<course_id>[^/]+/[^/]+/[^/]+)/cohorts/add$',
+            'course_groups.views.add_cohort',
+            name="add_cohort"),
+        url(r'^courses/(?P<course_id>[^/]+/[^/]+/[^/]+)/cohorts/(?P<cohort_id>[0-9]+)$',
+            'course_groups.views.users_in_cohort',
+            name="list_cohort"),
+        url(r'^courses/(?P<course_id>[^/]+/[^/]+/[^/]+)/cohorts/(?P<cohort_id>[0-9]+)/add$',
+            'course_groups.views.add_users_to_cohort',
+            name="add_to_cohort"),
+        url(r'^courses/(?P<course_id>[^/]+/[^/]+/[^/]+)/cohorts/debug$',
+            'course_groups.views.debug_cohort_mgmt',
+            name="debug_cohort_mgmt"),
+
     )
 
     # discussion forums live within courseware, so courseware must be enabled first