C# example of using Firebase REST API

Once I got my head around how Firebase worked (see here multiple Firebase related posts), my next step was to figure out a way to send data to it from C#, namely from TeamMentor.

To try it out, I used the Web C# REPL that is part of TeamMentor's admin section (which gives me a great interactive environment to quickly test new APIs).

Using AngularJS in Eclipse, Part 3) Wire up a Backend

This is the third of four posts on how to run (inside Eclipse) the examples provided in AngularJS's home page:

• Using AngularJS in Eclipse, Part 1) The Basics
• Using AngularJS in Eclipse, Part 2) Add Some Control 
• Using AngularJS in Eclipse, Part 3) Wire up a Backend
• Using AngularJS in Eclipse, Part 4) Create Components

The example covered on this post is the Wire up a Backend:

A really SIMPLE and clean AngularJS+Firebase example

As seen on the First PoC of sending TeamMentor's server-side request URLS to Firebase (and seeing it in realtime in an AngularJS page) I created a Simple AngularJS website which I'm very happy with (and I mean Simple with a capital S).

The main reason I really like the solution shown below, is because it represents a number of really nice, clean and Simple solutions for common (complex) problems that exist while developing in Javascript.

The created application is an:

• AngularJS real-time viewer for HTTP requests, 
• ... made to an ASP.NET web application (TeamMentor),  
• ... captured by an custom C# HttpHandler filter, 
• ... submitted to Firebase using its REST API and 
• ... pushed back to the AngularJS app using open HTML 5 WebSockets.

First PoC of sending TeamMentor's server-side request URLS to Firebase (and seeing it in realtime in an AngularJS page)

After getting my head around how Firebase works (see Using Firebase to sync data with a webpage (via Javascript, REST and Firebase Admin panel) and Trying our Firebase (Beta) hosting solution and good example of Firebase Security rules), I really wanted to see how it could work on a key feature that I've been wanting to add to TeamMentor for ages: Realtime viewing  of traffic and logs

And it worked :)

This is really exciting!!! (can you tell :)  ), specially since I can see so many great uses of this type of technique and technology in TeamMentor (for example it will allow for much better understanding on how the content is used, and for better collaboration between its readers (and authors))

Trying out Firebase (Beta) hosting solution and good example of Firebase Security rules

Since Firebase now offers a Beta hosting service (and I was looking for a quick way to publish one of the firebase PoCs I'm working at the moment), I decided to take it for a spin.

I have to say that I'm really impressed with the end result, and as you will see below, there entire process (from install to published website) was really smooth.

Note 1: in the example below I already had created an Firebase app to hold the data (see Using Firebase to sync data with a webpage (via Javascript, REST and Firebase Admin panel) for details on how to create one) 

Note 2: at the time I wrote this post, the website created is/was (depending on when you are reading this) hosted at https://tm-admin-test.firebaseapp.com/

Starting with the instructions from Firebase hosting page:

XSS considerations when developing with Firebase

Following my previous post on Using Firebase to sync data with a webpage (via Javascript, REST and Firebase Admin panel), here are a couple security notes and 'areas of concern', that should be taken into account when developing real-time apps with Firebase:

• Firebase will reflect any payloads sent to it
• We are talking about DOM based XSS
• The current browsers XSS protection does not protect against DOM based XSS
• It is very easy to create a vulnerability (as you will see below, all it takes is a simple change from .text() to .html())
• If powerful DOM based API-manipulation frameworks are used (like jQuery), there are many more injection points (sinks)
• By nature of Firebase applications, the XSS exploit will have wormable capabilities (i.e. it will be able to distribute and self-propagate itself VERY quickly)
• Current static-analysis tools will struggle to pick up this type of vulns

Note: I think (and I will want to double check this) that if is safe (i.e OK) to put received Firebase data/payloads, on an AngularJS auto-binded location/variable (for example {{name}} : {{message}} )

Let's use the chat application provided by Firebase to see this in action (note that as you will see below, the chat application as provided by Firebase, is secure and not exploitable)

Using Firebase to sync data with a webpage (via Javascript, REST and Firebase Admin panel)

If you haven't seen the Anant Narayanan presentation on AngularJS conference called Building realtime apps with Firebase and AngularJS you are missing something good.

Firebase really seems to fix one of the pain points that I currently have in client-server development, which is how to send/synchronise data across multiple clients (including the server).

I first heard about Firebase from the Wire up a Backend example that can be found at http://angularjs.org, and today I was able to give it a test drive (since I want to use it on the AngularJS front-ends that I'm currently developing for TeamMentor)