extract params for multiple 'routes' in a handler

Hey everyone-

I'm trying to figure out how to extract some optional params for multiple, but not all, routes or handlers within an action chain. (I'm probably improperly using those terms.)

See: https://github.com/joshdurbin/rx-mongo-ratpack/blob/master/src/main/groovy/io/joshdurbin/action/PeopleHandler.groovy

What I'm looking for is something more like the following where I extract the query parameters only for three of the four handlers defined in the chain.

  @Override
  void execute(Chain chain) throws Exception {

    Groovy.chain(chain) {

      all {

        Integer page = request.queryParams.page as Integer ?: 1
        Integer pageSize = request.queryParams.pageSize as Integer ?: persistenceServiceConfig.maxResultSizePerPage
        Integer evaluatedPageSize = pageSize <= persistenceServiceConfig.maxResultSizePerPage ? pageSize : persistenceServiceConfig.maxResultSizePerPage

        get("near/:lat/:long") {

          Double latitude = pathTokens.lat as Double
          Double longitude = pathTokens.long as Double

          persistenceService.getPeopleNearPoint(latitude, longitude, page, evaluatedPageSize).toList().subscribe() { List<Person> people ->

            render json(people)
          }
        }

        get("in/:postalCode") {

          String postalCode = pathTokens.postalCode

          persistenceService.getPeopleInPostalCode(postalCode, page, evaluatedPageSize).toList().subscribe() { List<Person> people ->

            render json(people)
          }

        }

        get {

          persistenceService.getPeople(page, evaluatedPageSize).toList().subscribe() { List<Person> people ->
            render json(people)
          }
        }
      }

      post {
        def form = parse(Form)

        persistenceService
          .insertPerson(form)
          .subscribe { Person person ->
            redirect "/person/${person.id}"
        }
      }
    }
  }

You can use the context registry for managing this kind of inter-handler communication.

import static ratpack.groovy.Groovy.ratpack

class PageModel {
        Integer page
        Integer pageSize
        Integer evaluatedPageSize
}

ratpack {
       
        bindings {
                module(JacksonModule)
                bind(PersistenceService, DefaultPersistenceService)
        }

        handlers {
                all { PersistenceService persistenceService ->
                        Integer page = request.queryParams.page as Integer ?: 1
                        Integer pageSize = request.queryParams.pageSize as Integer ?: persistenceServiceConfig.maxResultSizePerPage
                        Integer evaluatedPageSize = pageSize <= persistenceServiceConfig.maxResultSizePerPage ? pageSize : persistenceServiceConfig.maxResultSizePerPage
                        context.next(new PageModel(page: page, pageSize: pageSize, evaluatedPageSize: evaluatedPageSize))
                }

                all { PersistenceService persistenceService ->
                        byMethod {
                                get { PageModel pageModel ->
                                        persistenceService.getPeople(pageModel.page, pageModel.evaluatedPageSize).toList().subscribe() { List<Person> people ->
                                render json(people)
                                }
                                }
                                post {
                                        def form = parse(Form)
                                persistenceService
                                  .insertPerson(form)
                                  .subscribe { Person person ->
                                    redirect "/person/${person.id}"
                                  }
                                }

                        }
                }

        get("in/:postalCode") { PersistenceService persistenceService, PageModel pageModel ->
          String postalCode = pathTokens.postalCode
          persistenceService.getPeopleInPostalCode(postalCode, pageModel.page, pageModel.evaluatedPageSize).toList().subscribe() { List<Person> people ->
            render json(people)
          }
        }

        }
}

Better formatting of response => https://gist.github.com/danveloper/6ed3caaf0f4b192f99bd

Sweet. That makes sense, but the API doesn't seem to support that syntax -- adding a random object via context.next(...).

I changed it to context.next(single(

Ah yes -- my fault :-)

You need:

module JacksonModule

in your `bindings` block, here: https://github.com/joshdurbin/rx-mongo-ratpack/blob/master/src/ratpack/Ratpack.groovy#L23

Ahhh. Re: Ratpack, the module changed. Got it.

--

Any thoughts on the NPE with the addition of the PageModel to the registry? I still feel like I'm doing something wrong.

Request to /people yields:

java.lang.NullPointerException: Cannot get property 'page' on null object
        at org.codehaus.groovy.runtime.NullObject.getProperty(NullObject.java:57)
        at org.codehaus.groovy.runtime.InvokerHelper.getProperty(InvokerHelper.java:169)
        at org.codehaus.groovy.runtime.callsite.NullCallSite.getProperty(NullCallSite.java:44)
        at org.codehaus.groovy.runtime.callsite.AbstractCallSite.callGetProperty(AbstractCallSite.java:293)
        at io.joshdurbin.action.PeopleHandler$_execute_closure1$_closure3$_closure6$_closure7.doCall(PeopleHandler.groovy:52)

It's a “bug” of sorts.

The closures used inside `byMethod()` don't support registry extraction. You'd have to move the param up to the handler level. This is something we could potentially make work.

The fact that you are getting a null, and not a runtime (or compile time if using @CompileStatic) error when coercing a Closure to ratpack.func.Block is surprising though.

What version of Ratpack are you using?