Installing a Request Context add-on
One of the coolest features of Spincast is the ability to
extend the Request Context type.
The Request Context are objects, associated with a request, that Spincast automatically creates and passes
to your Route Handlers. You can extend the type of those object by adding add-ons.
Some plugins may suggest that you use one of their components as such add-on.
To do so, you first add the add-on entry point to your Request Context interface. This entry point is simply
a method, with a meaningful name, and that returns the add-on's main component :
public interface AppRequestContext extends RequestContext{ public WonderfulComponent wonderful(); //... other add-ons and methods }
Here, the add-on is named "wonderful()" and its main component is
"WonderfulComponent".
Then, you inject a Provider for the main component in your
Request Context implementation, and you use it to return component instances :
public class AppRequestContext extends RequestContextBase<AppRequestContext>
implements AppRequestContext {
private final Provider<WonderfulComponent> wonderfulComponentProvider;
@AssistedInject
public AppRequestContext(@Assisted Object exchange,
RequestContextBaseDeps<AppRequestContext> requestContextBaseDeps,
Provider<WonderfulComponent> wonderfulComponentProvider) {
super(exchange, requestContextBaseDeps);
this.wonderfulComponentProvider = wonderfulComponentProvider;
}
@Override
public WonderfulComponent wonderful() {
return this.wonderfulComponentProvider.get();
}
//...
}
It's a good practice to always use a
Provider for the
add-on's component, because it is often not a singleton and may even be
request scoped.
You can now use the newly installed add-on, directly in your Route Handlers!
For example :
public void myRouteHandler(AppRequestContext context) {
context.wonderful().doSomething();
//...
}