GAE for Mobile Part 3 – Servlet I/O

Did you miss GAE for Mobile Part1 or GAE for Mobile Part2?

Input/Output – Making the Servlet Useful

Input / doPost()

So far, the servlet described does absolutely nothing from a client perspective.  Since we can’t output data until data exists, let’s flesh out doPost() first, specifically the handling for RecipeIngredient.  Before I begin, I want to give a special thanks for a great article over at gae-java-persistence.blogspot.com on Querying with Key Parameters in GAE, I have implemented some of the concepts from this article in the code for doPost() and doGet().

GAE for Mobile Part 2 – RESTful server implementation

Did you miss GAE for Mobile Part 1?

The Development Environment

Before launching into a discussion on the server implementation, I wanted to mention that I am using Eclipse and Google Plugin for Eclipse.  I am writing in Java, although you can choose to write in Python as well.  If you haven’t gone through Google’s Tutorials then you should stop and do so.  Google does a fantastic job of walking through installation and configuration of the IDE, the creation of a simple app, user authentication and the datastore.

I <3 REST

I think everyone that knows REST feels the same.  If you haven’t done the necessary reading from Wikipedia and Java then here is the super lazy man’s guide to RESTful web services.  If you are a php dude and you want to get recipes from a database, you might write a file called getRecipes.php.  If you wanted to pull recipe 6 out you might call http://www.blah.com/getRecipes.php?id=6.

Notice that getRecipes is a verb, REST uses nouns instead of verbs.  To get all recipes from a RESTful service you would call http://www.blah.com/recipes/.  To get recipe 6 you would call http://www.blah.com/recipes/6.  If you wanted to update recipe 6 you would POST instead of GET in your HTML form/AJAX request.  That is RESTful web services 101.

GAE for Mobile Part 1 – Architecture, Classes and Relationships

Motivation

Some time ago, I wrote a C# based Cookbook that stores data on our local server, I then compiled it in Mono so it could run on our Ubuntu Netbook as well as our Windows computers. Providing a rich user experience on both platforms became very difficult, if I compiled in Visual Studio, everything looked as designed but the Netbook obviously couldn’t run it.  Compiling with Mono allowed the app to run on both platforms but it did not look as designed.

This became frustrating to maintain and develop, so I got the idea of creating a cloud-based Cookbook.  There are several advantages to this that I wanted to capitalize on:

1. We can access the Cookbook from anywhere without exposing our home server to the outside world.
2. We could easily allow friends and family read or write access to the Cookbook.
3. The server and client implementations are decoupled, meaning that anyone could write their own client to suit their needs.

Making a 3D Level using Blender

Since I am a horrible artist, I figured that it would be much easier to model than to draw.  For this reason I decided to do my first game in 3D.  My game uses a fixed camera view, the camera sits in one place and never moves (except possibly for special effects like camera shake).

Basics

Here is my first level prototype, it doesn’t get much more simple than this.