Over the last year, Tangram has changed very much and does not look the same in all of its modules and options.
Persistence Options
The Tangram Dynamic Web Application Framework has been extended to support the Java Persistence API (JPA) and EBean as persistence layers in addition to the already available Java Data Objects solution. This greatly extends the number of options for platforms to use with Tangram.
The Tangram examples reflect this with the JDO/DataNucleus, JDO/Google App Engine, EBean, and JPA example where the later is switchable with tested API implementations for OpenJPA, EclipseLink, DataNucleus, and Hibernate.
The simple and more or less generic JDO editor now is a generic editor
for all the storage solutions and built as a separate module. Except for
Google App Engine this module can be left out if there is another
solution available to get the content into the repository.
Dynamic Model Extenions
In addition to the Groovy implemented classes stored in the repository, which are used to extend the view and controller part of the application, you can now create JDO annotated classes which are immetiately usable as model classes in the repository. This option can only be presented for the JDO implementation.
To make the building of Tangram itself, any Tangram application, or even any application using byte-code transformation for JDO, JPA, and Ebean easier, a gradle plugin has been introduced. The examples and over blog entries illustrate the usage of this plugin.
IDE Integration
To be able to synchronize codes stored in the repository a separate FTP module has be introduced. Most IDE due to their strong PHP past support FTP better than any other protocol. CSS, JavaScript, Groovy codes can be imported and exported.
Generic Import and Export
Additionally and apart from the FTP module Tangram now contains a generic importer and exporter for the whole content stored in the repository. The XML representation can be used to transfer content between application using JPA, JDO, or EBean. IDs cannot be preserved.
Framework Independency
For the whole Tangram code the Springframework now is only an option to do the setup of the application by Spring's Dependency Injection IoC-Container and for the controller and view parts of the application.
Along this way it was easier to present a custom DI component, Dinistiq, than to use one of the available solutions. Tests have been done with Google Guice, TinyDI, and JSR-330. As of Tangram 0.9 none of these are more than experiments. Work on a Tangram JavaEE integration is also in an experimental stage and would require a major refactoring of some parts of Tangram, see other entries in this blog on the JavaEE topic.
It should now be fairly easy to do more experiments with other IoC/DI frameworks and containers or to integrate other web frameworks starting from the new plain servlet based solution.
Options
Tangram 0.9 has been tested, verified, or is even in production use on the following platforms: Google App Engine, run@CloudBees, OpenShift, and Standalone with Apache Tomcat using RDBMS or MongoDB.
The option matrix now looks like this:
Persistence: JDO, JPA, EBean
IoC: Springframework, Dinistiq
Security: Spring Security, Apache Shiro
Hosting: On Premise, OpenShift, Cloudbees, Google App Engine
Storage: RDBMS, No-SQL e.g. MongoDB, Files
Code Reduction
Tangram started as an idea to plug existing components together to form a web application with as little glue code as possible. Some of the ideas like object oriented templating though had to be coded explicitly. After this starting point the Tangram codes started growing and the 0.9 release got an additional design goal to stop this. Still some of the codes in Tangram duplicate functionality which would otherwise externally be available but avoids a depedency just to call one method. And there are still codes duplicates within Tangram where the different options e.g. for persistence might get a stronger common code base. In these areas it is still not clear if they will differentiate or grow together.
Outlook
The experiences with CapeDwarf showed the way into a Java EE module as an alternative to dinistiq, the Springframework, and the many tests with e.g. Google Guice. The not that encouraging experiences with the EBean ORM might lead to discontinued support for that module. Dinistiq will become more Java EE / CDI compatible and CDI without the full Java EE stack also seems to be an interesting option. Work on the generic import and export functions using XStream needs to be extended and easier integration of OpenID or OAuth outside of the Google App Engine is needed for many applications. Google App Engine with JPA is still on the list but not desperately needed.
