jquery - Need help making Django + Ajax like button -

i new coding , have implemented button online book - tango django:

http://www.tangowithdjango.com/book17/chapters/ajax.html#add-a-like-button

however project need record users have liked , ensure can item once (similar instagram/facebook). have looked @ other related questions online have found there no laid out answer other beginners follow. if easy follow answer me , other people trying achieve same in future, appreciated!

my current code follows:

models

class userproject(models.model):     user = models.foreignkey(user)     title = models.charfield(max_length=100)     date_created = models.datetimefield(auto_now_add=true)     project_likes = models.integerfield(default=0)     slug = models.slugfield(max_length=100, unique=true) 

views

@login_required def like_project(request):      proj_id = none     if request.method == 'get':         proj_id = request.get['project_id']      likes = 0     if proj_id:         proj = userproject.objects.get(id=int(proj_id))         if proj:             likes = proj.project_likes + 1             proj.project_likes = likes             proj.save()      return httpresponse(likes) 

template

<strong id="like_count">{{ project.project_likes }}</strong> likes            {% if user.is_authenticated %}                   <button id="likes" data-projid="{{project.id}}" class="btn btn-danger-outline btn-sm" type="button"> <i class="fa fa-heart-o" aria-hidden="true"></i>                                      </button>           {% endif %} 

url

url(r'^like_project/$', views.like_project, name='like_project'), 

ajax

$(document).ready(function() {  $('#likes').click(function(){     var projid;     projid = $(this).attr("data-projid");     $.get('/like_project/', {project_id: projid}, function(data){                $('#like_count').html(data);                $('#likes').hide();     }); }); }); 

if want make sure no user likes same userproject twice, can not store number of likes in project_likes field, should rather create separate model (e.g. userlikes) foreignkeys user , userproject, , e.g. time @ user liked userproject. can make function on userproject model count number of likes.