colin_dev256 colin_dev256 - 2 months ago 18
AngularJS Question

Datastore One-to-Many Google App Engine

I'm struggling to display my array items in the template. Just started with Entity relationships in GAE and I'm not finding suitable solutions on SO. Do i have to perform a query first in my handler. if so, how coz I'm struggling with the logic.


entities example display

enter image description here

entities example display

enter image description here

class Project(ndb.Model):
projectID = ndb.IntegerProperty(required=True)
title = ndb.StringProperty(required=True)
description = ndb.StringProperty(required=True)
startAt = ndb.DateTimeProperty(indexed=True)
endAt = ndb.DateTimeProperty()
isFullDay = ndb.BooleanProperty()
days = ndb.KeyProperty(kind='CompanyDay', repeated=True)
employees = ndb.KeyProperty(kind='Employees', repeated=True)
client = ndb.KeyProperty(kind='Client')

class Employees(ndb.Model):
name = ndb.StringProperty()
role = ndb.StringProperty()


is fetched from the backend through angular's

<md-content class="md-padding projects" layout="row" layout-wrap>
<md-card ng-repeat="data in controller.projects" flex="20" ng-click="editProject(data)">
<img src="" alt="">
<div class="project-info">
<h2 class="md-title">{{ data.title }}</h2>
<p>{{ data.description }}</p>
<p>{{ data.employees }}</p>


python code that responds to /comments

class commentsJsonHandler(webapp2.RequestHandler):
def route(cls):
name: index, template: /
return webapp2.Route('/comments', handler=cls, name='_commments_')

def get(self):
projects = Project.query()

def date_handler(obj):
print obj
if isinstance(obj, datetime):
return obj.isoformat()
return str(obj)

self.response.out.write(json.dumps([dict(proj.to_dict(), **dict( for proj in projects], default=date_handler))

from angular - code that reguests from server

var vm = this;
vm.projects = [];
.then(function(result) {
vm.projects =;

Displaying employees as from the datastore.

enter image description here


You could change your date_handler to handle ndb.Key to properly render your Employee collection in your returned json

def date_handler(obj):
    print obj
    if isinstance(obj, datetime):
        return obj.isoformat()
    elif isinstance(obj, ndb.Key):
      return obj.get().to_dict()
        return str(obj)

You may want to change the name of this method as it is not just doing date_handling any more