Unable to user handler in websocket tests in 1.4.1

[jrx-sjg]

Hi all.

I'm unable to use a handler when using karate.websocket(), as intented in the documentation.

The test is:

@ws-test
Feature: public test
    
@websocket
Scenario: only listening to websocket messages
    * def handler = function(msg) { karate.log('received:', msg); return msg.startsWith('hello'); }
    * def socket = karate.webSocket('wss://ws.postman-echo.com/raw', handler)
    * socket.send('hello world')
    * listen 5000
    * print listenResult

And the error I'm getting is:

[ERROR] Failures: 
[ERROR]   ExamplesTest.testParallel:15 js failed:
>>>>
01: karate.webSocket('wss://ws.postman-echo.com/raw', handler)
<<<<
org.graalvm.polyglot.PolyglotException: Cannot invoke "org.graalvm.polyglot.SourceSection.getCharacters()" because the return value of "org.graalvm.polyglot.Value.getSourceLocation()" is null
- com.intuit.karate.graal.JsFunction$Executable.<init>(JsFunction.java:95)
- com.intuit.karate.graal.JsFunction$Executable.<init>(JsFunction.java:89)
- com.intuit.karate.graal.JsFunction$Instantiable.<init>(JsFunction.java:132)
- com.intuit.karate.graal.JsLambda.<init>(JsLambda.java:37)
- com.intuit.karate.core.ScenarioBridge.webSocket(ScenarioBridge.java:1110)
- com.intuit.karate.core.ScenarioBridge.webSocket(ScenarioBridge.java:1101)
- <js>.:program(Unnamed:1)

classpath:examples/websocket/websocket.feature:7 ==> expected: <0> but was: <1>

This is something that only happens in karate 1.4.1, using 1.4.0 works normally and it calls the handler function and retrieve the messages as intended.

I've tried to use karate.toJava to call the handler, but didn't help.

I've tested everything in a new minimal maven karate template as explained in https://github.com/karatelabs/karate/wiki/How-to-Submit-an-Issue, and you can replicate everything in the code in the attached .zip using the command: mvn compile test

karate-template.zip

[ptrthomas]

@jrx-sjg thanks for the report, and it may take a while to get to this. I also wanted to be transparent about the fact that the websocket feature has not been very successful because of its design. recently we re-thought how to test async systems in general and are releasing a set of capabilities which will be closed-source. if you are interested I can let you know when websocket support lands, you can see a preview here: https://github.com/karatelabs/karate-addons/blob/main/karate-websocket/README.md

[jrx-sjg]

@ptrthomas thanks so much for the transparency.

My questions are? Will be the open-source basic websocket implementation fixed? What license will be necessary to get access to karate-websocket addon?

Having websocket support was something that made us decide to use karate in our company. However, the fact that it doesn't work in the latest version is something that blocks us a lot.

[ptrthomas]

@jrx-sjg

Will be the open-source basic websocket implementation fixed

yes, breakage of any existing functionality should be fixed. we also welcome PRs from the community

the license needed is described at the link above (runtime + IDE)

[ecidou]

Hello,
I'm trying to explore Karate's asynchronous capabilities and ran into the same issue with

1. the Websocket
2. and the karate.fork handler (and as above, it's OK with Karate 1.4.0, not the last ones)

[ptrthomas]

I was hoping this would be fixed in 1.5.0 but I guess not. for everybody's info - theorg.graalvm.polyglot.PolyglotException exceptions are because of severe issues with the JS engine we are using currently. we are working on a plan B, details here: #2546