NIS error following attempted websocket subscription

Technical Discussion
#1

I set up a node using the recommended docker build to troubleshoot websocket subscriptions, and have noted the following error in my NIS logs:

org.springframework.web.socket.sockjs.SockJsException: Uncaught failure in SockJS request, uri=http://165.227.217.87:7778/w/messages/814/db1bbcmk/eventsource; nested exception is org.springframework.web.socket.sockjs.SockJsTransportFailureException: Failed to open session; nested exception is java.lang.IllegalArgumentException: Async support must be enabled on a servlet and for all filters involved in async request processing. This is done in Java code using the Servlet API or by adding "<async-supported>true</async-supported>" to servlet and filter declarations in web.xml. Also you must use a Servlet 3.0+ container at org.springframework.web.socket.sockjs.support.SockJsHttpRequestHandler.handleRequest(SockJsHttpRequestHandler.java:93) at org.springframework.web.servlet.mvc.HttpRequestHandlerAdapter.handle(HttpRequestHandlerAdapter.java:51) at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:959) at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:893) at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:966) at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:857) at javax.servlet.http.HttpServlet.service(HttpServlet.java:687) at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:842) at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
…etc.

Any ideas how to address this? I’m just using the standard nem-sdk in nodejs to subscribe to block height, unconfirmed and confirmed transactions. Thanks.

#2

could you try nemlibrary.com ?

check this guide https://nemlibrary.com/guide/listener/

1 Like
#3

Thanks Aleix, shall take a look. I should say, it doesn’t happen all the time, but even when it’s not giving me the error, I can still only receive the block height push from the server.

Is there a way to see socket pushes in the logs? In the same way that you can see the ‘entering…’ and ‘exiting…’ for the endpoint requests?

#4

Using the nem library seems to work nicely. :slight_smile: Though as the transaction objects are different, I’ll have to spend a while rewriting the app to handle the different structures.

#5

Cool! :slight_smile:

I suggest you to, if you can, use nem-library in your project. When Catapult will be on main net you will need to use nem2-sdk, and it’s simple to nem-library. So, it will help you in the future

#6

Shall do! Will take a little while, but I’ll work on moving my apps over. It’ll be a good chance to get to grips with the library.

#7

which is your application? maybe it’s worth to start using Catapult instead

#8

NEMp3 and Wishing Wall. Would I have to apply for access?

#9

apply here http://mijin.io/en/catapult.

if you want to run the node in localhost use docker-compose → https://github.com/tech-bureau/catapult-service-bootstrap

but the beta it’s more complete, check it out!

1 Like
#10

Just an update, Aleix. I applied about 10 days ago, but haven’t heard anything back yet. Do you know how long it typically takes to greenlight a new applicant? Thanks.

#11

check the slack invitation link at the bottom of docs here https://nemtech.github.io/

and if you want to run catapult in local use this https://github.com/tech-bureau/catapult-service-bootstrap

1 Like
#12

Thanks!