[ 
https://issues.apache.org/jira/browse/WW-5704?focusedWorklogId=1041405&page=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-1041405
 ]

ASF GitHub Bot logged work on WW-5704:
--------------------------------------

                Author: ASF GitHub Bot
            Created on: 14/Sep/26 12:30
            Start Date: 14/Sep/26 12:30
    Worklog Time Spent: 10m 
      Work Description: asf-ci commented on PR #336:
URL: https://github.com/apache/struts-site/pull/336#issuecomment-5663943379

   Staged site is ready at https://struts.staged.apache.org/




Issue Time Tracking
-------------------

    Worklog Id:     (was: 1041405)
    Time Spent: 40m  (was: 0.5h)

> HTML5 required false-rejects on radio/file when the bound property is never 
> null
> --------------------------------------------------------------------------------
>
>                 Key: WW-5704
>                 URL: https://issues.apache.org/jira/browse/WW-5704
>             Project: Struts 2
>          Issue Type: Bug
>          Components: Core Tags
>            Reporter: Lukasz Lenart
>            Assignee: Lukasz Lenart
>            Priority: Major
>             Fix For: 7.4.0
>
>          Time Spent: 40m
>  Remaining Estimate: 0h
>
> Found reviewing WW-5695 (PR #1865). Violates that feature's governing rule: 
> emit a constraint only when the browser cannot reject input the server would 
> accept.
> h3. What happens
> {{StrutsHtmlConstraintProvider.addRequiredField}} emits {{required}} for 
> RADIO and FILE only, and its javadoc explains why:
> bq. A control that submits an empty string rather than omitting the parameter 
> therefore passes server-side while the browser blocks it [...] Only RADIO and 
> FILE omit the parameter entirely when empty, so only they agree with the 
> browser.
> That reasoning is about the HTTP request. {{RequiredFieldValidator}} never 
> sees the request - it inspects the already-bound property:
> {code:java}
> public void validate(Object object) throws ValidationException {
>     String fieldName = getFieldName();
>     Object value = this.getFieldValue(fieldName, object);
>     if (value == null) {
>         addFieldError(fieldName, object);
>     } else if (value.getClass().isArray() && Array.getLength(value) == 0) {
>         addFieldError(fieldName, object);
>     } else if (Collection.class.isAssignableFrom(value.getClass()) && 
> ((Collection) value).isEmpty()) {
>         addFieldError(fieldName, object);
>     }
> }
> {code}
> For a primitive-typed or otherwise default-initialised property the server 
> can therefore _never_ fail, while the browser's {{required}} still can.
> h3. Reproduction
> The action declares {{private int priority;}} with a {{required}} 
> field-validator on it, rendered as {{s:radio}} with {{name}} of {{priority}} 
> and a list of 1, 2, 3. On first render nothing is selected, because 0 is not 
> in the list.
> * Browser: no radio in the group is selected, so the submit is blocked.
> * Server: {{getFieldValue}} returns {{Integer.valueOf(0)}}, which is not 
> null, so no error is added and the form would have been accepted.
> Same shape for {{s:file}} whenever {{prepare()}} pre-populates the file 
> property from an existing entity, which is the ordinary edit-an-attachment 
> flow.
> h3. Why it is not simply fixable in the provider
> There is no render-time way to know a property's default value, so the two 
> honest options are:
> * drop the {{RequiredFieldValidator}} to {{required}} mapping entirely, 
> leaving only {{requiredstring}}; or
> * keep it and document it as a deliberate, narrow deviation from the 
> never-false-reject rule.
> h3. Not affected
> The {{requiredstring}} mapping is sound and should stay: 
> {{RequiredStringValidator}} fails on null, on empty, and by default on blank, 
> so the browser's {{required}} can only reject what the server would also 
> reject. That mapping reasons about the value, not the request, and so does 
> not have this defect.
> h3. Test gap
> No test renders {{required}} end-to-end on {{s:radio}} or {{s:file}}; only 
> {{minlength}} is asserted through a template.



--
This message was sent by Atlassian Jira
(v8.20.10#820010)

Reply via email to