Spring-based web application fails at startup on WAS Liberty - spring

Question

I'm writing a simple Spring-based web application and deploy it to Websphere Liberty 8.5.5.9. The deployment fails because the application start fails. The message in console.log is
[ERROR ] CWWKZ0002E: An exception occurred while starting the application userSetting.
The exception message was: com.ibm.ws.container.service.metadata.MetaDataException:
com.ibm.wsspi.adaptable.module.UnableToAdaptException:
com.ibm.ws.javaee.ddmodel.DDParser$ParseException: CWWKC2262E: The server is
unable to process the 3.1 version and the http://xmlns.jcp.org/xml/ns/javaee namespace
in the /META-INF/web-fragment.xml deployment descriptor on line 23.
The last part of the message makes now sense since I don't hav /META-INF or /WEB-INF in the Eclipse project for the application, since I'm deploying with Gradle: gradle clean build deploy.
I've tried all kinds of modifications to the project and, in desperation, I've cut it down to only have the following source code:
#SpringBootApplication
public class UserSettingApplication {
private static final LoggerUtils logger = new LoggerUtils( UserSettingApplication.class );
public static void main(String[] args) {
logger.debug( "Entering UserSettingApplication.main()" );
SpringApplication.run(UserSettingApplication.class, args);
}
}
Can you please advise me how to fix this service start-up problem?
server.xml:
<?xml version="1.0" encoding="UTF-8"?>
<server description="new server">
<!-- Enable features -->
<featureManager>
<feature>jsp-2.2</feature>
</featureManager>
<featureManager>
<feature>adminCenter-1.0</feature>
</featureManager>
<!-- Define the host name for use by the collective.
If the host name needs to be changed, the server should be
removed from the collective and re-joined. -->
<variable name="defaultHostName" value="localhost" />
<!-- Define an Administrator and non-Administrator -->
<basicRegistry id="basic">
<user name="admin" password="********" />
<user name="nonadmin" password="***********" />
</basicRegistry>
<!-- Assign 'admin' to Administrator -->
<administrator-role>
<user>admin</user>
</administrator-role>
<keyStore id="defaultKeyStore" password="*******" />
<!-- To access this server from a remote client add a host attribute to the following element, e.g. host="*" -->
<httpEndpoint id="defaultHttpEndpoint"
host="*"
httpPort="9080"
httpsPort="9443" />
<!-- Automatically expand WAR files and EAR files -->
<applicationManager autoExpand="false"/>
</server>

Answer 1

This error appears to be caused by some of your build tooling generating a web-fragment.xml with a Servlet 3.1 schema.
Currently, you have the jsp-2.2 feature enabled, which by default enables servlet-3.0.
To fix the problem, I would recommend upgrading from jsp-2.2 to jsp-2.3 (which will pull in servlet-3.1), or adding <feature>webProfile-7.0</feature> to just enable all of the Java EE 7 web profile features (servlet, JPA, bean validation, cdi, jsf, etc).
So your new server.xml could look like this:
<server description="new server">
<!-- Enable features -->
<featureManager>
<feature>jsp-2.3</feature>
<feature>adminCenter-1.0</feature>
</featureManager>
<!-- rest of file unchanged.... -->