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How to get Flutter WebSocket working with spring-boot backend?

I have tried many combinations of the values below, I have no idea why it isn't working. I don't even know if the problem is with frontend or backend setup. I pasted the relevant code parts below.
FLutter says the following when I try to connect (MYIPADDRESS is a valid IP address, the IP address of the pc):
WebSocketChannelException: WebSocketChannelException: WebSocketException: Connection to 'http://MYIPADDRESS:8080/topic/greetings#' was not upgraded to websocket
Here is the backend/spring-boot controller part:
#MessageMapping("/hello")
#SendTo("/topic/greetings")
public String send(final String message) throws Exception {
return message;
}
Here is the backend/spring-boot configuration part:
#Configuration
#EnableWebSocketMessageBroker
public class WebSocketConfig implements WebSocketMessageBrokerConfigurer {
#Override
public void configureMessageBroker(MessageBrokerRegistry config) {
config.enableSimpleBroker("/topic");
config.setApplicationDestinationPrefixes("/app");
}
#Override
public void registerStompEndpoints(StompEndpointRegistry registry) {
registry.addEndpoint("/websocket").withSockJS();
}
}
Here is the frontend/flutter part:
final channel = IOWebSocketChannel.connect(
Uri(
scheme: "ws",
host: "MYIPADDRESS",
port: 8080,
path: "/topic/greetings",
),
);

Spring boot Web Socket Connection loosing connection on production

I am using Angular, Spring Boot, and WebSocket in my project. I'm testing on my local machine socket connection is working fine but when I deployed my build on the production server it is not working properly. sometimes connection was established and sometimes not. I'm new to this technology.
I already configured the message broker and WebSocket application endpoints here is my code
#Configuration
#EnableWebSocketMessageBroker
public class WebSocketConfig implements WebSocketMessageBrokerConfigurer, WebSocketConfigurer {
#Override
public void registerStompEndpoints(StompEndpointRegistry registry) {
registry.addEndpoint("/chat").setAllowedOrigins("http://localhost:4200", "https://www.xxxxxx.com/").withSockJS();
}
#Override
public void configureMessageBroker(MessageBrokerRegistry registry) {
registry.setApplicationDestinationPrefixes("/app");
registry.enableSimpleBroker("/chatparticipant", "/messages", "/unAssignedParticipant");
}
#Bean
public ServletServerContainerFactoryBean createWebSocketContainer() {
ServletServerContainerFactoryBean container = new ServletServerContainerFactoryBean();
container.setMaxBinaryMessageBufferSize(1024000);
return container;
}
#Override
public void registerWebSocketHandlers(WebSocketHandlerRegistry registry) {
registry.addHandler(new WebSocketHandler(), "/socket").setAllowedOrigins(Pl4ChatConfig.ALLOWED_ORIGIN);
}
}
we're getting error messages:
WebSocket connection to 'wss://xxxxx.com/ws/709/2pjkwf4q/websocket' failed:

STOMP connection fails

I have a spring-boot service that provides a STOMP endpoint like so
#Configuration
#EnableWebSocketMessageBroker
public class WebSocketConfig implements WebSocketMessageBrokerConfigurer {
#Override
public void registerStompEndpoints(StompEndpointRegistry registry) {
registry.addEndpoint("/entityUpdates").withSockJS();
}
}
In the Angular frontend, I use this package to connect to the socket:
const url = 'ws://localhost:8080/entityUpdates';
const webSocketClient = new Client({ brokerURL: url });
webSocketClient.activate();
This throws following errors:
WebSocket connection to 'ws://localhost:8080/entityUpdates' failed:
My best guess is that the URL is somehow wrong, or I missed something when I registered the STOMP endpoint, but I can't figure out what it would be.

Get data from a web socket in a Spring Boot web application

I am new to both Spring Boot and Websockets.
I am comfortable with Java and have read a few things on Websockets and Spring Boot framework.
I need to communicate with a Web socket and get the data in an existing Spring Boot web app.
Can anyone let me know where I can start and any good online resources ? I did Google, but most of the examples are difficult for me to grasp in a short time. If possible, also explain it to me conceptually.
Thanks in advance

To create a basic websockeet applicaiton in spring boot
You will need to:
- First, Enable Websocket support, For example by using:
#Controller
public class GreetingController {
#MessageMapping("/hello")
#SendTo("/topic/greetings")
public Greeting greeting(HelloMessage message) throws Exception {
Thread.sleep(1000); // simulated delay
return new Greeting("Hello, " + message.getName() + "!");
}
}
- Second, Create a message-handling controller:
#Configuration
#EnableWebSocketMessageBroker
public class WebSocketConfig extends AbstractWebSocketMessageBrokerConfigurer {
#Override
public void configureMessageBroker(MessageBrokerRegistry config) {
config.enableSimpleBroker("/topic");
config.setApplicationDestinationPrefixes("/app");
}
#Override
public void registerStompEndpoints(StompEndpointRegistry registry) {
registry.addEndpoint("/gs-guide-websocket").withSockJS();
}
}
- Create a browser client
function connect() {
var socket = new SockJS('/gs-guide-websocket');
stompClient = Stomp.over(socket);
stompClient.connect({}, function (frame) {
setConnected(true);
console.log('Connected: ' + frame);
stompClient.subscribe('/topic/greetings', function (greeting) {
showGreeting(JSON.parse(greeting.body).content);
});
});
}
I think you can start with this example, https://spring.io/guides/gs/messaging-stomp-websocket/

Check out my answer to a similar question:
SockJS Java Client Implementation for non-web application
Within, you can find an example of a client able to send/receive websocket data.

Spring with STOMP over SockJS and Tomcat not upgrading to Websockets

I am building a Stateless Spring (4.2.4.RELEASE) Solution using STOMP over Websockets with SockJS and a Rest Endpoint using JWT to connect mobile devices with Full Duplex communication. I am using Tomcat 8.0.33 as a Web Server and testing using html with sockjs javascript client. The stomp protocol works fine using the http fallback but I can't make it using only a websocket protocol. I tried CORS in many ways but I am not sure that is a Tomcat Problem or just bad spring configuration. I tested my html even in the same domain and port and SockJS is still falling back into xhr or iframes.
WebScoketConfig.java
#EnableWebSocketMessageBroker
public class WebSocketConfig extends AbstractWebSocketMessageBrokerConfigurer
{
#Override
public void registerStompEndpoints(StompEndpointRegistry registry)
{
RequestUpgradeStrategy upgradeStrategy = new TomcatRequestUpgradeStrategy();
registry.addEndpoint("/ws").setHandshakeHandler(new DefaultHandshakeHandler(upgradeStrategy))
.setAllowedOrigins("*").withSockJS().setSessionCookieNeeded(false)
.setStreamBytesLimit(512 * 1024)
.setHttpMessageCacheSize(1000)
.setDisconnectDelay(30 * 1000);
}
#Override
public void configureClientOutboundChannel(ChannelRegistration registration) {
registration.taskExecutor().corePoolSize(50);
}
#Override
public void configureMessageBroker(MessageBrokerRegistry registry)
{
registry.enableSimpleBroker("/queue/", "/topic/");
// registry.enableStompBrokerRelay("/queue/", "/topic/");
registry.setApplicationDestinationPrefixes("/myapp");
}
public void configureWebSocketTransport(WebSocketTransportRegistration registration) {
registration.setMessageSizeLimit(500 * 1024);
registration.setSendBufferSizeLimit(1024 * 1024);
registration.setSendTimeLimit(20000);
}
}
WebSecurityConfig.java
public class WebSecurityConfig extends WebSecurityConfigurerAdapter
{
#Override
protected void configure(HttpSecurity http) throws Exception
{
http.csrf().disable()
.authorizeRequests()
.antMatchers("/**").permitAll();
}
#Override
protected void configure(AuthenticationManagerBuilder auth) throws Exception
{
}
}

I solved my problem, actually the code was good but the antivirus (Kaspersky) was closing the connection on my client browser just after opened. It forces SockJS to fallback into a different strategy. I tested the client with the antivirus turned off and the Websocket transport was beautifully running. Tested on mac & linux as well.