Add a message to the messageContext in the flow xml - spring

Question

I am implementing a forgot password process. The challenge phase would ask three previously answered questions and if they are correct it continues. However, if they are incorrect, i want to loop back to the challenge form this time with an error message stating that the answers were incorrect. Basically, I want something like this:
<view-state id="challengeForm" view="forgotPasswordChallengeView" model="challenge">
<binder>
<!-- http://stackoverflow.com/questions/10338472/debugging-spring-mvc-collection-binding -->
<binding property="questionAndAnswerList[0].answer.answer" />
<binding property="questionAndAnswerList[1].answer.answer" />
<binding property="questionAndAnswerList[2].answer.answer" />
</binder>
<on-entry>
<set name="viewScope.commandName" value="'challenge'" />
</on-entry>
<transition on="submit" bind="true" validate="true" to="checkChallenge" />
</view-state>
<action-state id="checkChallenge">
<evaluate expression="userManager.challengePasses( challange )" />
<transition on="true" to="resetPassword" />
<transition on="false" to="challengeForm">
<!-- ADD MESSAGE HERE -->
<evaluate expression="messageContext.addMessage( ... )" />
</transition>
</action-state>
...
As I see it now, i have 3 possible solutions:
Check the challenge answers in the Validator and add a message there, but this feels wrong to be doing work in the validation.
Pass the messageContext to the challengePasses method and if it fails, add the message there, but the userManager seems like it should be more like a plain service and just return a response rather than have to manage messages.
Create an new method that would be something like messageManager.addChallengeFailedMessage( messageContext ), probably the clearest separation of concerns but feels a little overboard.
So, what i am asking is: Is there a clean way to add messages to the messageContext directly in the flow XML?

Answer 1

I have also had this exact question in the past. What is the semantic meaning of 'validation' and what goes appropriately in the validator? I ultimately decided this type of operation should not be a part of the validator. I have used option 3 for cases similar to yours, though I agree it seems a little overboard. Option 2 isn't ideal since the method name challengePasses does not indicate that it will add error messages, and 'challengePassesAddedErrorIfNot` would be kind of ridiculous.