使线程上的对象可用于Dropwizard异常映射器

Question

We're using Dropwizard as a platform for our REST service and make use of its exception mappers to deal with any exceptions thrown during the user journey. We're using google guice for dependency injection.

In one of our use cases, when an exception is thrown, we need to attach some extra information to the response that is not available at the point where exception is thrown.

The following flow diagram highlights the use case.

Object A -> Object b -> Object C

Object A has the main input available which has the extra information and Object C is where the exception is thrown. Also, Object C is an adapter that talks to an external system and at the moment we don't have the option to carry our input from Object A through C.

When exception is thrown, the thread goes into an exception mapper from where the Response is returned.

Is there a way to make the input available in the exception mapper via some dropwizard/jersey/guice annotation magic ?

Answer 1

I've been able to do this by defining a RequestScoped (@RequestScoped) bean that can hold intermediary result and then injecting it into the dropwizard exception mapper using @Inject. Google Guice magic.