Add a technical overview page to the wiki

[mcollovati]

The page should provide information about the Hilla integration

• Reimplemented/extended components
• Spring removal hacks
• current limitations

This ticket can be used to collect findings and potential changes that could be applied to Hilla to make integration easier to implement and maintain (for Quarkus, but also other environments)

[mcollovati]

Partial list, work in progress

• created a shaded jar to contain the minimum possible set of Spring classes that allows to compile a module with Hilla components
  • ApplicationContext and directly referenced interfaces, classes and exceptions)
  • Subset of spring-web classes to be able to wrap the EndpointController instead of copy/paste its logics
  • To support Auto Grid feature, a subset of spring-data-common is requierd
• create a jandex index for Hilla
• Partial implementation of a custom ApplicationContext, required by EndpointInvoker and EndpointController
• Custom ViewAccessChecker integrated with Quarkus security
• Custom Atmosphere InjectableObjectFactory to inject required beans in PushEndpoint
• Custom security policy and form authentication mechanism
• Byte code manipulation to remove/replace calls to Spring classes
  • replacement of @Autowired annotation
  • TODO: list classes and methods

Hilla refactoring that may ease development and maintenance

• Replacement of field injection with constructor injection
• Remove direct usage of ApplicationContext in Hilla components, providing instead the required beans or collections of beans
• Hilla OOB Jandex index
• TODO: other to be added

Huge refactoring/breaking changes

• Hilla 2.3 Auto Grid: introduce Pageable abstraction to be used in ListService instead of using Spring org.springframework.data.domain.Pageable
• Introduce and abstraction for spring ResponseEntity to be used in EndpointController. This should allow reusing the Hilla controller in any servlet-based framework, by wrapping it.
• Another breaking refactoring, could be creating abstraction for request/response as in Vaadin so that the controller could be used even with not servlet toolkits (e.g. Vert.x, Micronaut, ...)

[mcollovati]

https://github.com/mcollovati/quarkus-hilla/wiki/TechnicalOverview

[mcollovati]

DevToolsDatabase disabled by removing the related META-INF/services file because it is strongly coupled with Spring; in particular, it uses ApplicationContextProvider that implements ApplicationContextAware, that is not provided nor handled by the extension.