Adding pre-processing stage into send-workflow button in Orbeon XForms Form runner

Question

I have a form in Orbeon Form runner where I needed to add external validation before submitting with 'workflow-send'. Can we add capability to 'workflow-send' button in properties-local.xml for that?

For the record, I have also implemented a button which does the validation and does certain actions when the validation results come back. So alternatively, can we add 'workflow-send' capability to that button of mine?

Answer 1

I have done this by making some changes to the persistence-model.xml file. This kind of validation needs to be done in the persistence stage. Because, what we need was a server-side validation (accessing database etc) that was called before saving the data and obviously before workflow-send.

I have commented out the old code snippets.

<!-- Respond to send button activation -->
<xforms:action ev:event="DOMActivate" ev:observer="fr-workflow-send-button">
    <xforms:send submission="validation-submission" />
    <!-- xforms:setvalue ref="instance('fr-persistence-instance')/submit-or-save-or-send">send</xforms:setvalue> 
        <xforms:dispatch name="fr-save-action" target="fr-persistence-model"> <xxforms:context 
        name="fr:check-data-valid" select="true()" /> </xforms:dispatch -->
</xforms:action>

<xforms:action ev:event="my-valid-action">
    <xforms:setvalue
        ref="instance('fr-persistence-instance')/submit-or-save-or-send">send</xforms:setvalue>
    <xforms:dispatch name="fr-save-action" target="fr-persistence-model">
        <xxforms:context name="fr:check-data-valid" select="true()" />
    </xforms:dispatch>
</xforms:action>

<xforms:instance id="validation-result">
    <dummy />
</xforms:instance>

<xforms:submission id="validation-submission"
    ref="xxforms:instance('fr-form-instance')" resource="http://localhost:8080/MyApp/OrbeonValidationServlet"
    method="post" replace="instance" instance="validation-result">
    <!-- Clear external errors just before doing external validation -->
    <xforms:delete ev:event="xforms-submit" nodeset="//@v:*" />
    <xforms:action ev:event="xforms-submit-done">
        <!-- Insert external validation results when done -->
        <xforms:insert nodeset="."
            origin="instance('validation-result')/v:data/*" />
        <!-- Show all errors on form -->
        <xforms:dispatch name="fr-visit-all" targetid="error-summary" />
        <!-- Update error summary for incremental mode -->
        <xforms:refresh />
        <xforms:dispatch name="fr-update" targetid="error-summary" />
        <xforms:dispatch name="my-valid-action" target="fr-persistence-model"
            if="count(instance('validation-result')/v:global-errors/*) 
            = 0" />
    </xforms:action>
</xforms:submission>

So basically

• I have implemented my-valid-action and validate-submission
• Placed validate-submission instead of workflow-send
• Dispatch my-valid-action only if there is no error
• Call workflow-send from my-valid-action

The last thing was binding validation-result to a fr:error-summary in my form.

One can try harder and make /OrbeonValidationServlet settable from properties-local.xml.