Jinaga App

The simplest way to build a collaborative web app.

What You Get

Real-time collaboration. After you follow these steps, you will have a web app that lets your users collaborate in real-time with one another. Changes made by one user in their browser will appear in other user's browsers instantly. Think real-time chat. For your whole application model.

Persistence. The app will also persist that data to MongoDB. You don't have to write any code to do that. You don't have to talk to the MongoDB API at all.

Security. Your app will be secure. Users will log in using their Google account. You can have some parts of your app open to the public, and other parts that require a login.

Universal back end. All of your application code will run on the client. Once the back end is up and running, you won't need to touch it again.

Saving data

To save something, you will record a Jinaga fact. A fact is a JSON document. By convention, you provide a type property to indicate what the document means.

var userGroup = {
  type: 'MyApp.UserGroup',
  identifier: 'papersdallas'
};
j.fact(userGroup);

Querying data

To query data, you will write a template function. A template function matches facts with a certain set of properties:

function meetingsInUserGroup(g) {
  return {
    type: 'MyApp.Meeting',
    userGroup: g
  };
}

Collections

Then you will create a Collection for the child objects.

function UserGroupViewModel(userGroup) {
  this.meetings = new jko.Collection(userGroup, [meetingsInUserGroup], MeetingViewModel);
  var meetingsWatch = this.meetings.watch();
}

A view model will be added to the collection whever a fact is created. This could happen when it's loaded from the MongoDB storage, when the user on this browser adds a child, or when a user on another browser adds a child. Bind to the view models in Knockout JS.

Mutable properties

Programming with facts is very different from programming with properties. But you can simulate properties using facts. Create a Mutable in the child view model:

function MeetingViewModel(meeting, vm) {
  this.title = new jko.Mutable('MyApp.Meeting.Title', meeting, '(new meeting)');
}

Watch for changes to that mutable property.

  // In the UserGroupViewModel
  jko.watchMutable(meetingsWatch, 'title', 'MyApp.Meeting.Title');

Capture the current value of a mutable property so you can data bind it to a modal.

  var title = this.title.capture();

And then when the user saves changes, just save.

  title.save();

The property will be updated on this browser, and on all other browsers currently looking at the same object.

Continue on to installing