@ApplicationScoped does not work correctly in combination with @ServerEndpoint

[Neoministein]

Environment Details

• Helidon Version: 3.2.2
• Helidon MP
• JDK version: 17
• OS: Win 10
• Docker version (if applicable): -

---

Problem Description

I've got a websocket endpoint that I've registered with the @ServerEndpoint annoation. I've also added the CDI scope @ApplicationScoped to that class.

When I open multiple connections to the endpoint only instance is created. However when I close a connection the instance of the endpoint is destroyed and a new one is created and therefore all data in it is lost.

I would expect that since I annoated it with @ApplicationScoped that it wouldn't be destroyed and stay alive until the application is shut down.

Steps to reproduce

Here is a simple project with a test which recreates the issue.

Java code

I am using the following Helidon dependencies:

• helidon-microprofile-core
• helidon-microprofile-websocket
• helidon-microprofile-tests-junit5

And non Helidon dependency:

        <dependency>
            <groupId>org.junit.jupiter</groupId>
            <artifactId>junit-jupiter-api</artifactId>
            <version>5.9.3</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.junit.jupiter</groupId>
            <artifactId>junit-jupiter-engine</artifactId>
            <version>5.9.3</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.glassfish.tyrus</groupId>
            <artifactId>tyrus-container-grizzly-client</artifactId>
            <version>2.0.4</version>
            <scope>test</scope>
        </dependency>

Websocket endpoint:

package com.neo.example.issue.helidon;

import jakarta.enterprise.context.ApplicationScoped;
import jakarta.websocket.OnMessage;
import jakarta.websocket.OnOpen;
import jakarta.websocket.Session;
import jakarta.websocket.server.PathParam;
import jakarta.websocket.server.ServerEndpoint;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

@ApplicationScoped
@ServerEndpoint(value = "/websocket/{id}")
public class WebsocketEndpoint {

    protected Map<String, List<String>> messageMap = new HashMap<>();

    @OnOpen
    public void onOpen(@PathParam("id") String id, Session session) {
        messageMap.put(id, new ArrayList<>());
    }

    @OnMessage
    public void onMessage(@PathParam("id") String id, Session session, String message) {
        messageMap.get(id).add(message);
    }

    public Map<String, List<String>> getMessageMap() {
        return messageMap;
    }
}

Junit Test:

package com.neo.example.issue.helidon;

import io.helidon.microprofile.tests.junit5.HelidonTest;
import jakarta.inject.Inject;
import jakarta.websocket.*;
import jakarta.ws.rs.client.WebTarget;
import org.glassfish.tyrus.client.ClientManager;
import org.junit.jupiter.api.Assertions;
import org.junit.jupiter.api.Test;

import java.net.URI;
import java.util.List;
import java.util.Map;

@HelidonTest
class IssueTest {

    @Inject
    protected WebsocketEndpoint websocketEndpoint;

    @Inject
    protected WebTarget webTarget;

    protected Map<String, List<String>> messageMap;

    @Test
    void test() throws Exception {
        Session session_1 = connectToWebsocket("websocket/id-1");
        session_1.getBasicRemote().sendText("A message 1");

        Session session_2 = connectToWebsocket("websocket/id-2");
        session_2.getBasicRemote().sendText("A message 1");

        Thread.sleep(1000);

        messageMap = websocketEndpoint.getMessageMap();
        Assertions.assertEquals("A message 1", messageMap.get("id-1").get(0));
        session_2.close();

        messageMap = websocketEndpoint.getMessageMap();
        Assertions.assertEquals("A message 1", messageMap.get("id-1").get(0)); //<-- Throws NullPointerException for messageMap
    }

    public Session connectToWebsocket(String path) {
        Endpoint endpoint = new Endpoint() {
            @Override
            public void onOpen(Session session, EndpointConfig config) {}
        };

        try {
            return ClientManager.createClient().connectToServer(endpoint, new URI("ws://127.0.0.1:" + webTarget.getUri().getPort() + "/" + path));
        } catch (Exception ex) {
            throw new RuntimeException(ex);
        }
    }
}

[spericas]

As a workaround, does it work correctly if the you create a helper bean in application scope and inject it into the endpoint class?

[Neoministein]

It works correctly when using a helper bean in application scoped.

[Neoministein]

Thanks for fixing it so fast!