Question

I would much appreciate some help on rendering a JSON object on client-side from a Google App Engine entity.

Here is all of my relevant code:

def render_str(template, **params):
   t = jinja_env.get_template(template)
   return t.render(params)

class BlogHandler(webapp2.RequestHandler):
   def write(self, *a, **kw):
      self.response.out.write(*a, **kw)

   def render_str(self, template, **params):
      params['user'] = self.user
      return render_str(template, **params)

   def render(self, template, **kw):
      self.write(self.render_str(template, **kw))

class Post(ndb.Model):
   subject = ndb.TextProperty(required = True)
   created = ndb.DateTimeProperty(auto_now_add = True)
   startdate = ndb.DateTimeProperty()
   enddate = ndb.DateTimeProperty()

class PostPage(BlogHandler):
    def get(self, post_id):
    key = ndb.Key('Post', int(post_id), parent=blog_key())
    post = key.get()
    postdict = post.to_dict()
    postdict['startdate'] = postdict['startdate'].isoformat()
    self.render("permalink.html", postdict = postdict)

In my script tag on the template page, I include

<script>
var jsonobject = JSON.parse({{ postdict['startdate']}});
var jsonobject1 = new Date(jsonobject);
</script>

Am I on the right track here? I would like to ultimately use the datetime object on the client-side for some Jquery functions.

Any help in pointing me in the right direction would be much appreciated.

Answer 1

There are a number of problems with your code. First of all, once you convert post to a dictionary postdict, you can't reference the elements with the dot notation. You have to use a dictionary reference postdict['startdate'] to reference the startdate element.

Next, I use the isoformat() function when storing a date in JSON format:

postdict['startdate'] = postdict['startdate'].isoformat()

This makes it easier to convert to a Javascript Date object:

<script>
var jsonobject = JSON.parse({{ postdict.jsonobject}});
jsonobject[0].y = new Date(jsonobject[0].y);
</script>

How to render JSON on client-side from Google App Engine Entity

1 个答案: