grahambrooks / bvira

Demonstration reference architecture and test example. Bvira is based on the architecture of a social media project I was involved in some years ago.

bvira - sample web application

Bvira is a reference/example web application modeled on an extremely successful project. The application architecture exhibited a very clean separation of concerns and overall the project demonstrated how a number of principles and practices contributed to the success of the project.

Build Times

After 3+ months of development the project build and unit test cycle was less that 2 minutes. (Bvira is very primitive by comparison and currently builds and tests in 8 seconds). A short build time meant that developers could concentrate on delivering value through application features.

Self contained source and dependencies

Everything that is required to build and test the application in development is stored under version control. Developers were responsible for adding, updating and removing dependencies from the appropriate lib folder manually. All build tools were also stored in the repository.

This single source of truth meant that new developers could be up and running by installing a JDK and checking out the source repository.

Keeping the dependencies small was everyone's business.

Bvira is missing a persistence capability. The project that inspired bvira used an in-memory hypersonic in development to keep the builds fast.

Some characteristics of Bvira

Requests handling

Requests are handled and routed by a custom servlet to component classes. Each component class handles a number of paths. POST requests are routed to Command classes that accept parameters and then using the Post-Redirect-Get pattern return the URI for the later GET request. Get requests are again routed to a component to a presenter for the requested URI.

Response rendering

Bvira using stringtemplate for content templates. StringTemplate (http://www.stringtemplate.org) has a very clean separation of concerns and by design does not allow any business logic within the template.

Dependency injection

Capabilities like dependency injection are placed behind a facade that only exposes the functionality required by the application. Currently dependency injection is provided by PicoContainer (http://picocontainer.codehaus.org) but because it is behind application classes it can be quite easily replaced as additional requirements are identified.

bvira's Issues

As a developer I would like to see a complete workflow involving persistence

Consider hibernate and hypersonic for the sample. This would also help flesh out configuration handling.

Add raw acceptance and functional tests for comparison

Add comparison tests to illustrate the value of an abstraction layer in the test code.

Sample: Add a comment

As a site user I want to be able to comment on a recipe so my opinion is heard

Create a new controller and view

As a developer I want a simple command that will create a new view,
and controller for a specific url so I can write my application more
quickly without worrying about wiring code.

Sample: Add new recipe

As a cook I want to be able to add a new recipe so I can share it with others

Sample: Log in

As a cook I want to log in so I can add recipes

Sample: See new recipes on the home page

As a cook I want to see a list newly added recipes on the home page

Sample: Update recipe

As a cook I want to edit a recipe that I have written

Creating a new web application

As a developer I want a simple command that will create all the basic
files for a web application in my chosen technology so I can start
writing functional code more quickly.

Tasks

• Separate out the core bvira functionality into a core jar for
  distribution
• Create a command line tool that creates a basic application,
  including the ant script and other ancillary files.
• Add templates for the required source and test files
• Create an eclipse project file
• Create an IntelliJ project file