[Bug] server mode throws error about "replpp.server.WebServiceWithWebSocket$basicAuth" not implemented

[BrianMehrman]

Hi there, I am trying to get the server mode started so I can query a CPG from a python script.

There is a possibility that I have not setup something correctly.

I have tried a precompiled version, then tried to debug the problem locally with no success.

I when I trying the server mode using a simple test post requests I get an error.

curl http://localhost:8080/query-sync -X POST -d '{"query": "val bar = foo + 1"}'

This request returns the following error.

java.lang.AbstractMethodError: Receiver class replpp.server.WebServiceWithWebSocket$basicAuth does not define or inherit an implementation of the resolved method abstract wrapFunction(Lcask/model/Request;Lscala/Function2;)Lcask/router/Result; of interface cask.router.Decorator.
        at cask.router.Decorator$.invoke(Decorators.scala:47)
        at cask.main.Main$DefaultHandler.handleRequest(Main.scala:123)
        at io.undertow.server.Connectors.executeRootHandler(Connectors.java:395)
        at io.undertow.server.HttpServerExchange$1.run(HttpServerExchange.java:861)
        at org.jboss.threads.ContextHandler$1.runWith(ContextHandler.java:18)
        at org.jboss.threads.EnhancedQueueExecutor$Task.run(EnhancedQueueExecutor.java:2513)
        at org.jboss.threads.EnhancedQueueExecutor$ThreadBody.run(EnhancedQueueExecutor.java:1538)
        at org.xnio.XnioWorker$WorkerThreadFactory$1$1.run(XnioWorker.java:1282)
        at java.base/java.lang.Thread.run(Thread.java:834)

Steps to reproduce the behavior:

1. Install Joern
2. Start Joern in server mode
3. Run command curl http://localhost:8080/query-sync -X POST -d '{"query": "val bar = foo + 1"}'
4. See error

Expected behavior
From the Joern server documentation i expect to see this output

$ joern-remote 'val foo = 42'
> val foo: Int = 42

Desktop (please complete the following information):

• OS: MacOS Sequoia 15.1.1 (Apple M4 Max(
• Joern Version: v4.0.195
• Java version: openjdk 21.0.5 2024-10-15 LTS

Additional context

Upon trying to get the Dev Container working I did have to migrate the Centos7 image to Ubuntu, however I have not seen any side effects from this change. The CLI still works.

Please let me know if you need any further information.

[Codefiring]

I have occured the same problem.
I am not familiar with scala. I can only find the server mode is implemented in the git repo scala-repl-pp

[mpollmeier]

thanks for reporting, I'll take a look

[heedongy]

I have also occured the same problem.
Although I’m not entirely sure, it seems to be caused by some libraryDependencies version upgrades (Scala 3.5.2 update).
(8fa3240)

I solved it temporarily by rolling back to scala-3.4.2 and reverting the libraryDependencies to their previous versions.

--- a/build.sbt
+++ b/build.sbt

-ThisBuild / scalaVersion := "3.5.2"
+ThisBuild / scalaVersion := "3.4.2"

-val cpgVersion = "1.7.15"
+val cpgVersion = "1.7.13"

--- a/project/Versions.scala
+++ b/project/Versions.scala

-  val cask                   = "0.10.2"
+  val cask                   = "0.9.2"

-  val phpParser              = "4.15.10"
+  val phpParser              = "4.15.9"

-  val scalaReplPP            = "0.3.8"
+  val scalaReplPP            = "0.3.6"

-  val upickle                = "4.0.2"
+  val upickle                = "3.3.1"

Hope this helps!