I’m writing a simple chat with ajax and I have a problem with JSON. I need username instead of id.
JSON seems like:
[{"pk": 41, "model": "chat.post", "fields": {"timestamp": "2012-01-27 22:14:46", "user": 1, "text": "weq"}}]`
I need replace "user": 1 to "user": username.
How I can do it?
My model:
from django.db import models
from django.contrib.auth.models import User
class Post(models.Model):
timestamp = models.DateTimeField(auto_now_add=True)
text = models.TextField()
user = models.ForeignKey(User)
class Meta:
ordering = ['-id']
def __unicode__(self):
return "[%s] %s by user: %s" % (
self.timestamp.strftime("%Y-%m-%d %H:%M:%S"),
self.text,
self.user
)
My view:
# -*- coding: utf-8 -*-
#!/usr/bin/env python
from django.http import HttpResponse
from django.core import serializers
from django.contrib.auth.decorators import login_required
from django.http import HttpResponseRedirect
from django.contrib.auth.decorators import login_required
from django.template import RequestContext
from django.shortcuts import render_to_response
from live.chat.models import Post
@login_required
def updates_after(request, id):
response = HttpResponse()
response['Content-Type'] = "text/javascript"
response.write(serializers.serialize("json",
Post.objects.filter(pk__gt=id)))
# __gt - greaten then > id
return response
@login_required
def saymessage(request):
if request.method == 'POST':
if "text" in request.POST:
text = request.POST["text"]
user = request.user
message = Post()
message.user, message.text = user, text
message.save()
return HttpResponseRedirect('/')
else:
pass
JSON response example:
[
{
“pk”: 42,
“model”: “chat.post”,
“fields”: {
“timestamp”: “2012-01-28 18:08:44”,
“user”: 1,
“text”: “dasd”
}
}
]
My template:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8" />
<!-- Always force latest IE rendering engine (even in intranet) & Chrome Frame
Remove this if you use the .htaccess -->
<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1" />
<title>templates</title>
<meta name="description" content="" />
<script type="text/javascript" language="javascript" src="/media/js/jquery.min.js"></script>
<script type="text/javascript" language="javascript">
function update() {
update_holder = $("#update_holder");
most_recent = update_holder.find("div:first");
$.getJSON("/live/updates-after/" + most_recent.attr('id') + "/",
function(data) {
cycle_class = most_recent.hasClass("odd") ? "even" : "odd";
jQuery.each(data, function(){
update_holder.prepend('<div id="' + this.pk
+ '" class="update ' + cycle_class
+ '"><div class="timestamp">'
+ this.fields.timestamp
+ '</div><div class="user">'
+ this.fields.user
+ '</div><div class="text">'
+ this.fields.text
+ '</div><div class="clear"></div></div>'
);
cycle_class = (cycle_class == "odd") ? "even" : "odd";
});
}
);
}
$(document).ready(function() {
setInterval("update()", 10000);
})
</script>
<link rel="stylesheet" type="text/css" href="/media/css/main.css" />
</head>
<body>
{% block content %}
<div>
<header>
<h1>Live Update site</h1>
<p>Содержимое обновляется автоматически</p>
</header>
{% if object_list %}
<div id="update_holder">
{% for object in object_list %}
<div class="update {% cycle even,odd %}" id="{{ object.id }}">
<div class="timestamp">
{{ object.timestamp|date:"Y-m-d H:i:s" }}
</div>
<div class="user">
{{ object.user }}
</div>
<div class="text">
{{ object.text|linebreaksbr }}
</div>
<div class="clear"></div>
</div>
{% endfor %}
</div>
{% else %}
<p>Нет обновлений</p>
{% endif %}
</div>
<form enctype="multipart/form-data" action="{% url chat.views.saymessage %}" method="post">{% csrf_token %}
Введите текст сообщения: <input type="text" name="text" id="text">
<input type="submit" name="submit" value="Отправить">
</form>
{% endblock %}
</body>
</html>
Update:
I figure out this problem, we need using natural_key(), and overrive this method in user manager class, add next code to models.py:
class UserManager(models.Manager):
def unatural_key(self):
return self.username
User.natural_key = unatural_key
And dont forget add argument use_natural_keys=True to serializers.serialize()
You might want to look into Natural Keys. Natural keys allow you to specify what foreign key fields are serialized to. By constructing a primary key for your user, you can have the username in the serialization, instead of the ID.