Brett Ryan opened SPR-16617 and commented

Using the spring jstl form tag attribute servletRelativeAction with a value that starts with the context path strips off this from the value rendered.

Steps to Reproduce

1. Create a new webapp deployed at location /foo with a spring MVC context mapped to /
2. Create a form JSP using the following content

   <%@ page pageEncoding="UTF-8" trimDirectiveWhitespaces="true" %>
   <%@ taglib uri="http://www.springframework.org/tags/form" prefix="form" %>
   <form:form servletRelativeAction="/foo/my-action" method="POST">
   </form:form>
   <form:form servletRelativeAction="/bar/my-action" method="POST">
   </form:form>

1. Create a mapping to the above form and observe the output.

Expected Behavior

Form should render as follows:

<form id="command" action="/foo/foo/my-action" method="POST">
</form>
<form id="command" action="/foo/bar/my-action" method="POST">
</form>

Actual Behavior

Form is actually rendered without the leading context path for the first form entry:

<form id="command" action="/foo/my-action" method="POST">
</form>
<form id="command" action="/foo/bar/my-action" method="POST">
</form>

Workaround

Do not use the spring JSTL form implementation and instead use <c:url value="/"/> to provide the output context path.

<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<form action="<c:url value="/foo/my-action"/>" method="POST">
</form>

Alternatively using the spring <form:form> implementation use the action attribute by providing the pageContext's context path:

<form:form action="${pageContext.request.contextPath}/foo/my-action" method="POST">
</form:form>

---

Affects: 5.0.4

Comment From: snicoll

The Javadoc for servletRelativeAction states:

Action reference to be appended to the current servlet path.

/foo shouldn't be added there as it should be the relative action.