mkouba / cdi-extensions-demo

CDI Extensions Demo

This is a demo project for Quarkus Insights #122.

It compares 2 approaches for integrating with the CDI container in Quarkus:

• Build Compatible Extensions, as defined by CDI Lite
• Quarkus extensions

Therefore, there are 2 demonstration projects, both implementing the same use case.

Use Case

The demo consists of a hypothetical, CDI-based framework. It is not very realistic, but covers many important concerns.

Users of the framework are supposed to provide beans that implement a simple interface:

interface Processor {
    void doWork();
}

The framework provides a bean of type ProcessorManager which allows obtaining all Processor instances. For this, the extension must:

1. participate in type discovery.

Further, the framework makes sure that all implementations of Processor.doWork() are intercepted with a LoggingInterceptor. For this, the extension must:

2. alter annotations on application classes.

Further, the processor implementations may be annotated @Important, which changes the log level used by the interceptor. For this, the extension must:

3. inspect beans that exist in the container,
4. create a synthetic bean and pass data from the extension to runtime.

Finally, the extension validates that at least one Processor implementation actually exists. For this, the extension must:

5. perform custom validation of the deployment.

Usage

This is not a multi-module Maven project. There's a parent POM only for centralizing some boilerplate. All modules must be built independently.

First of all, install the parent POM and the framework core classes to the local Maven repository for later resolution:

mvn clean install

cd framework
mvn clean install

cdi-lite

cd cdi-lite/integration
mvn clean install

cd ../user
mvn clean test

quarkus

cd quarkus/integration
mvn clean install

cd ../user
mvn clean test