On transition evaluate redirect to a view without showing FacesMessage

Hello
On transition, my flow redirect without rendering the FacesMessage contained in the FacesContext current instance, the issue is the same with the MessageContext.

The service layer is functionally tested so it might not come from this area.

the whole code is available there

the portion who should causing troubles are linked there :
RegistrationController.groovy

enterRegistration.xhtml

web.xml

applicationContext.xml


in the flow xml definition file the statement

PHP Code:

---

    <view-state id="enterRegistration" model="model">
        <transition on="cancelRegistrationAction" to="exitRegistrationAction"/>
        <transition on="validateRegistrationAction" to="reviewRegistration">
            <evaluate expression="registrationController.validate(model)"/>
        </transition>
    </view-state> 


---

should display the facesmessages, instead it's redirect to the next step on the next view with messages into the facescontext (spyed on the console) but not rendered

what's wrong?

Ok I found a workaround, but still dont know what "court-circuite" the JSF lifecycle to not let the message be displayed inside an evaluate of a transition, so I had to use a decision-state to block the transition and change the controller method signature

PHP Code:

---

import javax.faces.application.FacesMessage
import javax.faces.context.FacesContext
import javax.inject.Inject
import javax.inject.Named
import javax.servlet.http.HttpServletRequest

@Named("registrationController")
class RegistrationController {

    static final Logger log = LoggerFactory.getLogger(RegistrationController)

    @Inject
    @LangServiceQualifier
    ILangService langService

    @Inject
    @RegistrationServiceQualifier
    IRegistrationService registrationService

    Lang registrationLang() {
        return langService.supportedLangs.find {
            it.code == FacesContext
                    .currentInstance
                    .externalContext
                    .requestLocale
                    .language
        } as Lang ?: langService.defaultLang
    }

    Boolean validateModel(RegistrationModel registrationModel) {
        FacesContext context = FacesContext.currentInstance
        ResourceBundle bundle = ResourceBundle.getBundle(
                II18nConfigService.BUNDLE_BASE_NAME_VALUE,
                context.viewRoot.locale,
                Thread.currentThread().contextClassLoader)
        registrationModel.user.profile.lang ?: registrationModel.user.profile.setLang(registrationLang())
        try {
            registrationService.validate(registrationModel)
            registrationModel.header = new RequestHelper(
                    request: context
                            .externalContext
                            .request as HttpServletRequest).header
        } catch (RegistrationException re) {
            assert !re.messages.empty
            re.messages.each {
                switch (it) {
                    case new UsernameAlreadyExistsException().message:
                        context.addMessage "register_form_username_inputText_id",
                                new FacesMessage(
                                        severity: FacesMessage.SEVERITY_ERROR,
                                        summary: bundle.getString(it))
                        break
                    case new PrimaryEmailAlreadyExistsException().message:
                        context.addMessage "register_form_currentEmailValue_inputText_id",
                                new FacesMessage(
                                        severity: FacesMessage.SEVERITY_ERROR,
                                        summary: bundle.getString(it))
                        break
                    case new EmailRetypeException().message:
                        context.addMessage "register_form_currentEmailValueRetype_inputText_id",
                                new FacesMessage(
                                        severity: FacesMessage.SEVERITY_ERROR,
                                        summary: bundle.getString(it))
                        break
                    case new PasswordRetypeException().message:
                        context.addMessage "register_form_password_inputText_id",
                                new FacesMessage(
                                        severity: FacesMessage.SEVERITY_ERROR,
                                        summary: bundle.getString(it))
                        break
                }
            }
            return Boolean.FALSE
        }
        return Boolean.TRUE
    }
} 


---

Code:

---

<?xml version="1.0" encoding="UTF-8"?>
<flow xmlns="http://www.springframework.org/schema/webflow"
      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      xsi:schemaLocation="http://www.springframework.org/schema/webflow
                http://www.springframework.org/schema/webflow/spring-webflow-2.0.xsd">
    <on-start>
        <evaluate expression="requestParameters.contains('from')?requestParameters.get('from'):'home'"
                  result="flowScope.from"/>
        <evaluate expression="registrationService.initModel()"
                  result="flowScope.registrationModel"/>
    </on-start>

    <view-state id="enterRegistration" model="registrationModel">
        <transition on="validateRegistrationAction" to="isValidModelDecision">
            <evaluate expression="registrationController.validateModel(registrationModel)"
                      result="flowScope.isValidModel"/>
        </transition>
        <transition on="cancelRegistrationAction" to="exitRegistrationAction" history="discard"/>
    </view-state>

    <decision-state id="isValidModelDecision">
        <if test="isValidModel" then="reviewRegistration" else="enterRegistration"/>
    </decision-state>

    <view-state id="reviewRegistration" model="registrationModel">
        <transition on="reviseRegistrationAction" to="enterRegistration"/>
        <transition on="confirmRegistrationAction" to="exitRegistrationAction">
            <evaluate expression="registrationService.register(registrationModel)" />
        </transition>
        <transition on="cancelRegistrationAction" to="exitRegistrationAction" history="discard"/>
    </view-state>

    <end-state id="exitRegistrationAction" view="externalRedirect:#{from}"/>
</flow>

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the first version of the method was returning void wich was relevant for the evaluate who seems in that case let the the flow transite to next step, so the initial problem was to give a boolean value as a return value in the method evaluated in the evaluate balise.... end of story