Add a little bar chart to the admin list to show number of updates taken from reversion data

admin.py

add field 'updates' to the end of list_display

eg.

class MyAdmin(reversion.VersionAdmin):

    class Meta:
        model = MyModel

    list_display = ('framework_panel', 'level_of_court','seniority', 'updates')
    

and add this to the same admin class:
  
    def updates(self, obj):

        return format_html('<div class="sparks" id="spark_{0}" data-content-type-id="{1}" data-object-id="{0}"></div>',
                           obj.id,
                           self.content_type)

    updates.allow_tags = True

base_site.html

add this to admin/base_site.html


{%  block extrahead %}

        <style>


            div.bar {
                display: inline-block;
                width: 5px;
                height: 50px;
                margin-right: 2px;
                background-color: blueviolet;
                padding-bottom: 0px;
            }

            div.sparks {
                border-bottom: 1px solid;
                border-bottom-color: cornflowerblue;
            }
        </style>
        <script src="http://d3js.org/d3.v3.min.js" charset="utf-8"></script>
        <script type="text/javascript" charset="utf-8">

            (function($) {
                $(document).ready(function() {

                    var updates = d3.selectAll(".sparks");


                    updates[0].forEach(function(spark) {

                        d3.json("/get_updates/"+spark.dataset.contentTypeId+"/"+spark.dataset.objectId+"/", function(error, json) {

                            d3.select("#"+spark.id)
                                    .selectAll(".bar")
                                    .data(json)
                                    .enter()
                                    .append("div")
                                    .attr("class", "bar")
                                    .style("height", function(d) {
                                        var barHeight = d.updates * 10;
                                        return barHeight + "px";
                                    });


                        });

                    });
                    $(".sparks").on("click", function() {
                        document.location = this.baseURI + this.dataset.objectId+"/history/";
                    });

                });


            })(grp.jQuery);
        </script>

{% endblock %}

urls.py

point to your view:
  
    url(r'^get_updates/(?P<content_type>\w+)/(?P<obj_id>\w+)/(?P<daysback>\w+)/', 'get_obj_updates'),
                          

views.py

Create a function to extract the data in an appropriate place like views.py


from django.contrib.admin.views.decorators import staff_member_required
from django.views.decorators.cache import cache_control
from django.http import HttpResponse
from django.core.serializers.json import DjangoJSONEncoder

from datetime import timedelta
import json

from reversion.models import Revision, Version



@cache_control(no_cache=True)
@staff_member_required
def get_obj_updates(request, content_type, obj_id, daysback=30):

    today = datetime.today()
    fromdate = today - timedelta(days=daysback)


    # for each date, create list of changes

    items = Version.objects.filter(object_id_int=obj_id, content_type=content_type, revision__date_created__gt=fromdate).values('revision__date_created', 'revision__user__username', 'revision__comment').order_by('revision__date_created')
    lastdate = items[0]['revision__date_created']

    data = [{'updates': 0,
             }]*daysback

    change_list = []
    count = 0
    n = 0
    num_items = len(items)

    for item in items:
        n += 1

        if lastdate.date() != item['revision__date_created'].date():

            data[(lastdate - fromdate).days] = {
                         'updates': count,
                         }


            count = 0
            change_list = []


        count += 1
        lastdate = item['revision__date_created']
 
        if n==num_items:
            data[(lastdate - fromdate).days] = {
                         'updates': count,
                         }


    jsondata = json.dumps(data, cls=DjangoJSONEncoder)


    return HttpResponse(jsondata, mimetype="application/json", content_type="application/json")