Jhipster executable jar with undertow does not work - 404 - jhipster

Question

I built a jhipster application. Added an entity. Built it with
mvn -Pprod package
Application runs fine with tomcat when I use
java -jar xyz.war
But, since we need Undertow for high load scenarios and fast startup time, I simply change the maven dependency from Tomcat to Undertow in all the places (all the profiles) wherever tomcat starter dependency was mentioned as per the Spring documentation : Using Undertow in Place of Tomcat
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
<exclusions>
<exclusion>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-tomcat</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-undertow</artifactId>
</dependency>
This runs fine when run from Eclipse and I can see the requests are now served by Undertow and not Tomcat as logs print XNIO as the thread-id.
But., when I again build it and try to run it with java -jar xyz.war,
Application boots up fine but when I hit the URLs
http://127.0.0.1:8081
or http://127.0.0.1/xyz
it says not found.
What else do I need to do to put jHipster application with Undertow embedded to work?
Any quick help appreciated as a critical POC to push jHipster in our organization hinges on this step.

Answer 1

We used to support Undertow, but removed it recently. So you shouldn't have much trouble setting it up back (and what you do looks good, then you don't post your whole configuration so it's hard to tell).
Anyway, concerning your specific use-case, you need to know why we removed Undertow:
Start-up time is indeed lower, by something like 300-500ms. We were mostly using this in our "dev" profile, as start-up time is important. But now that we have the Spring Dev Tools hot restart, this isn't useful at all anymore.
For "prod" usage, I haven't seen any performance difference between Tomcat and Undertow. Compared to just one database access (costing several ms), I guess you can't see this kind of improvements.
Besides, we have removed Undertow because it lacks a number of important features for us. Most importantly:
GZip compression support -> as you will lose this, your performance will in fact be much worse with Undertow than with Tomcat
Websocket support
Last but not least, it's easy to scale up your JHipster application by adding new nodes (and it will be even easier in JHipster 3.0), so handling a large number of users shouldn't be an issue.

Answer 2

I didn't manage to have your error. Undertow seems to work fine for me.
1) I generated a new JHipster project (from master), all default options
2) I replace tomcat by undertow only in this part of pom.xml :
<profiles>
<profile>
<id>dev</id>
<activation>
<activeByDefault>true</activeByDefault>
</activation>
<properties>
<!-- log configuration -->
<logback.loglevel>DEBUG</logback.loglevel>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-undertow</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<optional>true</optional>
</dependency>
</dependencies>
</profile>
<profile>
<id>prod</id>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-undertow</artifactId>
</dependency>
</dependencies>
3) Build :
mvn package -Pprod
4) Start database :
docker-compose -f src/main/docker/prod.yml up -d
5) Start app
java -jar target/*.war --spring.profiles.active=prod
:: JHipster 🤓 :: Running Spring Boot 1.3.2.RELEASE ::
:: http://jhipster.github.io ::
2016-02-22 00:18:40.051 INFO 6118 --- [ main] com.mycompany.myapp.JhundertowApp : Starting JhundertowApp on pgrXps with PID 6118 (started by pgrimaud in /home/pgrimaud/workspace/tests2/32-undertow)
2016-02-22 00:18:40.054 INFO 6118 --- [ main] com.mycompany.myapp.JhundertowApp : The following profiles are active: prod
2016-02-22 00:18:44.024 WARN 6118 --- [ main] io.undertow.websockets.jsr : UT026009: XNIO worker was not set on WebSocketDeploymentInfo, the default worker will be used
2016-02-22 00:18:44.126 WARN 6118 --- [ main] io.undertow.websockets.jsr : UT026010: Buffer pool was not set on WebSocketDeploymentInfo, the default pool will be used
2016-02-22 00:18:44.742 INFO 6118 --- [ main] c.mycompany.myapp.config.WebConfigurer : Web application configuration, using profiles: [prod]
6) I change log in app to confirm it runs with undertow
----------------------------------------------------------
Application 'jhundertow' is running! Access URLs:
Local: http://127.0.0.1:8080
External: http://127.0.1.1:8080
----------------------------------------------------------
2016-02-22 00:20:20.585 TRACE 6118 --- [ XNIO-2 task-31] c.m.m.c.l.AngularCookieLocaleResolver : Parsed cookie value [%22en%22] into locale 'en'
2016-02-22 00:20:25.741 TRACE 6118 --- [ XNIO-2 task-32] c.m.m.c.l.AngularCookieLocaleResolver : Parsed cookie value [%22en%22] into locale 'en'

Answer 3

Fortunately for me, when I move the same war file to a RHEL system, it works just fine. :-) I am accepting #pgrimaud 's answer. Thanks #deepu and #Julien. You guys are awesome.
I will investigate what's going wrong on my Win7 machine-will post back here if I am able to figure out. (npm clear cache dint help. Will re-install node.js and npm as I had updated them for my other node.js work - I will see if that helps). I will also try to debug spring-boot-starter-undertow.

Answer 4

Finally, a solution for the nemesis is in place. Here is an update from me - Today, I started to debug spring boot and undertow code and realized that spring boot is looking for resources in the below locations :
private static final String[] CLASSPATH_RESOURCE_LOCATIONS = {
"classpath:/META-INF/resources/", "classpath:/resources/",
"classpath:/static/", "classpath:/public/" };
After that, I created a folder called resources inside the META-INF directory and copied all the resources inside it using 7zip. And lo & behold., it works! :-).
Although spring boot is supposed to also load resources from
private static final String[] SERVLET_RESOURCE_LOCATIONS = { "/" };
for some reason, it is not doing so. (which is where jHipster is putting all of the resource files)
I thought this to be a bug with spring boot version that jHipster uses and I upgraded my app spring boot version to 1.3.3.RELEASE , but that does not help either.