Class Loader Constraint Violation for class io.grpc.Channel in IntelliJ plugin when trying to use GRPC

[AyushVachaspati]

I'm trying to setup grpc client to make inference requests to Nvidia Triton inference server (version:23.06-py3) in Kotlin for my project.

I've setup protoc code generation using gradle (attached build.gradle.kts below), but when I try to create a ManagedChannel to pass to the InferenceService Coroutine, I get this Runtime Error

val channel = ManagedChannelBuilder.forTarget("127.0.0.1:8001")
            .usePlainText()
            .build()
val inferenceStub = GRPCInferenceServiceGrpcKt.GRPCInferenceServiceCoroutineStub(channel)
val modelLive = inferenceStub.modelReady(
    GrpcService.ModelReadyRequest.newBuilder()
         .setName("santacoder_huggingface")
         .build()
)

2023-11-21 00:26:39,588 [  53359] SEVERE - #c.i.o.a.i.FlushQueue - loader constraint violation: loader com.intellij.util.lang.PathClassLoader @1c53fd30 wants to load abstract class io.grpc.Channel. A different abstract class with the same name was previously loaded by com.intellij.ide.plugins.cl.PluginClassLoader @3553bb79. (io.grpc.Channel is in unnamed module of loader com.intellij.ide.plugins.cl.PluginClassLoader @3553bb79, parent loader 'bootstrap')
java.lang.LinkageError: loader constraint violation: loader com.intellij.util.lang.PathClassLoader @1c53fd30 wants to load abstract class io.grpc.Channel. A different abstract class with the same name was previously loaded by com.intellij.ide.plugins.cl.PluginClassLoader @3553bb79. (io.grpc.Channel is in unnamed module of loader com.intellij.ide.plugins.cl.PluginClassLoader @3553bb79, parent loader 'bootstrap')
	at java.base/java.lang.ClassLoader.defineClass2(Native Method)
	at java.base/java.lang.ClassLoader.defineClass(ClassLoader.java:1103)
	at com.intellij.util.lang.UrlClassLoader.consumeClassData(UrlClassLoader.java:253)
	at com.intellij.util.lang.ZipResourceFile.findClass(ZipResourceFile.java:114)
	at com.intellij.util.lang.JarLoader.findClass(JarLoader.java:63)
	at com.intellij.util.lang.ClassPath.findClassInLoader(ClassPath.java:246)
	at com.intellij.util.lang.ClassPath.findClass(ClassPath.java:179)
	at com.intellij.util.lang.UrlClassLoader.findClass(UrlClassLoader.java:203)
	at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:587)
	at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:520)
	at io.grpc.stub.AbstractStub.<init>(AbstractStub.java:73)
	at io.grpc.kotlin.AbstractCoroutineStub.<init>(AbstractCoroutineStub.kt:34)
	at inference.GRPCInferenceServiceGrpcKt$GRPCInferenceServiceCoroutineStub.<init>(GrpcServiceGrpcKt.kt:146)
	at inference.GRPCInferenceServiceGrpcKt$GRPCInferenceServiceCoroutineStub.<init>(GrpcServiceGrpcKt.kt:143)
	at com.artemus.completionProvider.ArtemusCompletionProvider.getInlineCompletion(ArtemusCompletionProvider.kt:79)
	at com.artemus.inlineCompletionApi.InlineCompletionsManager$createPreviewInline$1.invokeSuspend(InlineCompletionsManager.kt:29)
	at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt:33)
	at kotlinx.coroutines.DispatchedTask.run(DispatchedTask.kt:106)
	at kotlinx.coroutines.EventLoopImplBase.processNextEvent(EventLoop.common.kt:274)
	at kotlinx.coroutines.BlockingCoroutine.joinBlocking(Builders.kt:85)
	at kotlinx.coroutines.BuildersKt__BuildersKt.runBlocking(Builders.kt:59)
	at kotlinx.coroutines.BuildersKt.runBlocking(Unknown Source)
	at kotlinx.coroutines.BuildersKt__BuildersKt.runBlocking$default(Builders.kt:38)
	at kotlinx.coroutines.BuildersKt.runBlocking$default(Unknown Source)
	at com.artemus.inlineCompletionApi.InlineCompletionsManager.createPreviewInline(InlineCompletionsManager.kt:29)
	at com.artemus.inlineCompletionApi.listeners.DocumentListener.documentChangedNonBulk$lambda$2(DocumentListener.kt:78)
	at com.intellij.openapi.application.TransactionGuardImpl.runWithWritingAllowed(TransactionGuardImpl.java:209)
	at com.intellij.openapi.application.TransactionGuardImpl.access$100(TransactionGuardImpl.java:21)
	at com.intellij.openapi.application.TransactionGuardImpl$1.run(TransactionGuardImpl.java:191)
	at com.intellij.openapi.application.impl.ApplicationImpl.runIntendedWriteActionOnCurrentThread(ApplicationImpl.java:881)
	at com.intellij.openapi.application.impl.ApplicationImpl$3.run(ApplicationImpl.java:513)
	at com.intellij.openapi.application.impl.FlushQueue.doRun(FlushQueue.java:75)
	at com.intellij.openapi.application.impl.FlushQueue.runNextEvent(FlushQueue.java:118)
	at com.intellij.openapi.application.impl.FlushQueue.flushNow(FlushQueue.java:42)
	at java.desktop/java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:318)
	at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:779)
	at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:730)
	at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:724)
	at java.base/java.security.AccessController.doPrivileged(AccessController.java:399)
	at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:86)
	at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:749)
	at com.intellij.ide.IdeEventQueue.defaultDispatchEvent(IdeEventQueue.java:898)
	at com.intellij.ide.IdeEventQueue._dispatchEvent(IdeEventQueue.java:746)
	at com.intellij.ide.IdeEventQueue.lambda$dispatchEvent$6(IdeEventQueue.java:439)
	at com.intellij.openapi.progress.impl.CoreProgressManager.computePrioritized(CoreProgressManager.java:791)
	at com.intellij.ide.IdeEventQueue.lambda$dispatchEvent$7(IdeEventQueue.java:438)
	at com.intellij.openapi.application.TransactionGuardImpl.performActivity(TransactionGuardImpl.java:105)
	at com.intellij.ide.IdeEventQueue.performActivity(IdeEventQueue.java:604)
	at com.intellij.ide.IdeEventQueue.lambda$dispatchEvent$8(IdeEventQueue.java:436)
	at com.intellij.openapi.application.impl.ApplicationImpl.runIntendedWriteActionOnCurrentThread(ApplicationImpl.java:881)
	at com.intellij.ide.IdeEventQueue.dispatchEvent(IdeEventQueue.java:484)
	at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:207)
	at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:128)
	at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:117)
	at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:113)
	at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:105)
	at java.desktop/java.awt.EventDispatchThread.run(EventDispatchThread.java:92)
2023-11-21 00:26:39,590 [  53361] SEVERE - #c.i.o.a.i.FlushQueue - IntelliJ IDEA 2022.2  Build #IC-222.3345.118
2023-11-21 00:26:39,591 [  53362] SEVERE - #c.i.o.a.i.FlushQueue - JDK: 17.0.3; VM: OpenJDK 64-Bit Server VM; Vendor: JetBrains s.r.o.
2023-11-21 00:26:39,591 [  53362] SEVERE - #c.i.o.a.i.FlushQueue - OS: Windows 11
2023-11-21 00:26:39,591 [  53362] SEVERE - #c.i.o.a.i.FlushQueue - Plugin to blame: Artemus version: 0.0.1

I've tried setting class loader to the Intellij Plugin Class loader inside the code like this, put it didn't help with the error.

val currentThread = Thread.currentThread()
val originalClassLoader = currentThread.getContextClassLoader()
val pluginClassLoader = this.javaClass.getClassLoader()
println("Original loader: $originalClassLoader")
println("Plugin loader: $pluginClassLoader")
try {
    currentThread.setContextClassLoader(pluginClassLoader)
    println("CL inside try block: ${currentThread.contextClassLoader}")
    val channel = ManagedChannelBuilder.forTarget("127.0.0.1:8001")
        .usePlaintext()
        .build();
    val inferenceStub = GRPCInferenceServiceGrpcKt.GRPCInferenceServiceCoroutineStub(channel)
    val modelLive = inferenceStub.modelReady(
        GrpcService.ModelReadyRequest.newBuilder()
            .setName("santacoder_huggingface")
            .build()
    )
    println("#".repeat(100))
    println(modelLive)
    println("#".repeat(100))
    channel.shutdown()
}
finally {
    currentThread.setContextClassLoader(originalClassLoader)
}

fun properties(key: String) = providers.gradleProperty(key)
fun environment(key: String) = providers.environmentVariable(key)

plugins {
  id("java")
  alias(libs.plugins.kotlin) // Kotlin support
  alias(libs.plugins.gradleIntelliJPlugin) // Gradle IntelliJ Plugin
  alias(libs.plugins.changelog) // Gradle Changelog Plugin
  alias(libs.plugins.qodana) // Gradle Qodana Plugin
  id("com.google.protobuf") version "0.9.4"
}

group = properties("pluginGroup").get()
version = properties("pluginVersion").get()

repositories {
  mavenCentral()
}

kotlin {
  jvmToolchain(17)
}

intellij {
  pluginName = properties("pluginName")
  version = properties("platformVersion")
  type = properties("platformType")

  plugins = properties("platformPlugins").map { it.split(',').map(String::trim).filter(String::isNotEmpty) }
}


val grpcVersion = "1.59.0"
val protobufVersion = "3.25.1"
val kotlinGrpcVersion = "1.4.0"

dependencies {
//  implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.6.3")
//  implementation("org.jetbrains.kotlinx:kotlinx-coroutines-swing:1.6.3")

  implementation("io.grpc:grpc-netty-shaded:$grpcVersion")
  implementation("io.grpc:grpc-protobuf:$grpcVersion")
  implementation("io.grpc:grpc-stub:$grpcVersion")

  implementation("com.google.protobuf:protobuf-java:$protobufVersion")
  implementation("com.google.protobuf:protobuf-java-util:$protobufVersion")
  implementation("com.google.protobuf:protobuf-kotlin:$protobufVersion")
  implementation("io.grpc:protoc-gen-grpc-kotlin:$kotlinGrpcVersion")


}

protobuf {
  protoc {
    artifact = "com.google.protobuf:protoc:$protobufVersion"
  }

  plugins {
    create("grpc") {
      artifact = "io.grpc:protoc-gen-grpc-java:$grpcVersion"
    }
    create("grpckt") {
      artifact = "io.grpc:protoc-gen-grpc-kotlin:$kotlinGrpcVersion:jdk8@jar"
    }
  }
  generateProtoTasks {
    all().forEach {
      it.plugins {
        create("grpc")
        create("grpckt")
      }
      it.builtins {
        create("kotlin")
      }
    }
  }
}

tasks {
  wrapper {
    gradleVersion = properties("gradleVersion").get()
  }

  patchPluginXml {
    version = properties("pluginVersion")
    sinceBuild = properties("pluginSinceBuild")
    untilBuild = properties("pluginUntilBuild")
  }

  signPlugin {
    certificateChain = environment("CERTIFICATE_CHAIN")
    privateKey = environment("PRIVATE_KEY")
    password = environment("PRIVATE_KEY_PASSWORD")
  }

  publishPlugin {
    token = environment("PUBLISH_TOKEN")
    channels = properties("pluginVersion").map { listOf(it.split('-').getOrElse(1) { "default" }.split('.').first()) }
  }
}

I thought this might be caused by grpc-netty-shaded dependency I have in the gradle file but I'm not sure since I'm very new to this. I tried removing grpc-netty-shaded in favour of grpc-netty, and also tried to remove the dependency entiry, but both of them lead to this error

2023-11-17 15:25:48,470 [   7696]  ERROR - pplication.impl.LaterInvocator - io.grpc.ManagedChannelProvider: io.grpc.netty.shaded.io.grpc.netty.NettyChannelProvider not a subtype 
java.util.ServiceConfigurationError: io.grpc.ManagedChannelProvider: io.grpc.netty.shaded.io.grpc.netty.NettyChannelProvider not a subtype
	at java.base/java.util.ServiceLoader.fail(ServiceLoader.java:588)
	at java.base/java.util.ServiceLoader$LazyClassPathLookupIterator.hasNextService(ServiceLoader.java:1236)
	at java.base/java.util.ServiceLoader$LazyClassPathLookupIterator.hasNext(ServiceLoader.java:1264)
	at java.base/java.util.ServiceLoader$2.hasNext(ServiceLoader.java:1299)
	at java.base/java.util.ServiceLoader$3.hasNext(ServiceLoader.java:1384)
	at io.grpc.ServiceProviders.loadAll(ServiceProviders.java:67)
	at io.grpc.ManagedChannelRegistry.getDefaultRegistry(ManagedChannelRegistry.java:101)
	at io.grpc.ManagedChannelProvider.provider(ManagedChannelProvider.java:43)
	at io.grpc.ManagedChannelBuilder.forTarget(ManagedChannelBuilder.java:86)
	at com.artemus.completionProvider.ArtemusCompletionProvider.getInlineCompletion(ArtemusCompletionProvider.kt:13)
	at com.artemus.inlineCompletionApi.InlineCompletionsManager$createPreviewInline$1.invokeSuspend(InlineCompletionsManager.kt:27)
	at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt:33)
	at kotlinx.coroutines.DispatchedTask.run(DispatchedTask.kt:106)
	at kotlinx.coroutines.EventLoopImplBase.processNextEvent(EventLoop.common.kt:284)
	at kotlinx.coroutines.BlockingCoroutine.joinBlocking(Builders.kt:85)
	at kotlinx.coroutines.BuildersKt__BuildersKt.runBlocking(Builders.kt:59)
	at kotlinx.coroutines.BuildersKt.runBlocking(Unknown Source)
	at kotlinx.coroutines.BuildersKt__BuildersKt.runBlocking$default(Builders.kt:38)
	at kotlinx.coroutines.BuildersKt.runBlocking$default(Unknown Source)
	at com.artemus.inlineCompletionApi.InlineCompletionsManager.createPreviewInline(InlineCompletionsManager.kt:27)
	at com.artemus.inlineCompletionApi.listeners.DocumentListener.documentChangedNonBulk$lambda$2(DocumentListener.kt:78)
	at com.intellij.openapi.application.TransactionGuardImpl.runWithWritingAllowed(TransactionGuardImpl.java:216)
	at com.intellij.openapi.application.TransactionGuardImpl.access$200(TransactionGuardImpl.java:24)
	at com.intellij.openapi.application.TransactionGuardImpl$2.run(TransactionGuardImpl.java:199)
	at com.intellij.openapi.application.impl.ApplicationImpl.runIntendedWriteActionOnCurrentThread(ApplicationImpl.java:822)
	at com.intellij.openapi.application.impl.ApplicationImpl.lambda$invokeLater$4(ApplicationImpl.java:324)
	at com.intellij.openapi.application.impl.FlushQueue.doRun(FlushQueue.java:85)
	at com.intellij.openapi.application.impl.FlushQueue.runNextEvent(FlushQueue.java:134)
	at com.intellij.openapi.application.impl.FlushQueue.flushNow(FlushQueue.java:47)
	at com.intellij.openapi.application.impl.FlushQueue$FlushNow.run(FlushQueue.java:190)
	at java.desktop/java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:313)
	at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:776)
	at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:727)
	at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:721)
	at java.base/java.security.AccessController.doPrivileged(Native Method)
	at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:85)
	at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:746)
	at com.intellij.ide.IdeEventQueue.defaultDispatchEvent(IdeEventQueue.java:976)
	at com.intellij.ide.IdeEventQueue._dispatchEvent(IdeEventQueue.java:843)
	at com.intellij.ide.IdeEventQueue.lambda$dispatchEvent$8(IdeEventQueue.java:454)
	at com.intellij.openapi.progress.impl.CoreProgressManager.computePrioritized(CoreProgressManager.java:773)
	at com.intellij.ide.IdeEventQueue.lambda$dispatchEvent$9(IdeEventQueue.java:453)
	at com.intellij.openapi.application.impl.ApplicationImpl.runIntendedWriteActionOnCurrentThread(ApplicationImpl.java:822)
	at com.intellij.ide.IdeEventQueue.dispatchEvent(IdeEventQueue.java:501)
	at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:203)
	at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:124)
	at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:113)
	at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:109)
	at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
	at java.desktop/java.awt.EventDispatchThread.run(EventDispatchThread.java:90)
2023-11-17 15:25:48,472 [   7698]  ERROR - pplication.impl.LaterInvocator - IntelliJ IDEA 2020.3  Build #IC-203.5981.155 
2023-11-17 15:25:48,473 [   7699]  ERROR - pplication.impl.LaterInvocator - JDK: 11.0.9; VM: OpenJDK 64-Bit Server VM; Vendor: JetBrains s.r.o. 
2023-11-17 15:25:48,473 [   7699]  ERROR - pplication.impl.LaterInvocator - OS: Windows 10 
2023-11-17 15:25:48,473 [   7699]  ERROR - pplication.impl.LaterInvocator - Plugin to blame: Artemus version: 0.0.1 
2023-11-17 15:25:48,473 [   7699]  ERROR - pplication.impl.LaterInvocator - Last Action: EditorEnter 

I'm completely lost as to how to resolve this issue. I'd really appreciate any help on this.
I found probably a relevant thread on this #2375 , but I don't have enough knowledge to properly understand the implications of this thread.
@ejona86 you commented #2375 (comment) which seems relevant to my error. I request you to please guide me in fixing this issue, it has become a major blocker for my project and I'm unable to get any help for it.

[ejona86]

gRPC only uses the context class loader if using the class loader holding io.grpc produces no results.

I don't know the structure of IntelliJ class loader. Looks like it may be broken to some degree (as is the state for a lot of the Java ecosystem). I think I've heard of an IntelliJ plugin that shaded gRPC. But I don't think we can help unless you told us what was going wrong (like where the other Channel came from and the structure of the class loaders).

[AyushVachaspati]

I'm not sure how I can provide you with these details. This is one thing I found when I was investigating where the different versions of the Channel class were coming from (not sure if this is helpful in any way)

I also got in touch with @karollewandowski on JetBrains slack. He tried quite hard to help me resolve the issue, he should have more knowledge of the IntelliJ ecosystem.

Please let me know what other details I can provide. I really want to solve this issue as it's quite a major blocker for me, as Triton Inference server only supports streaming through gRPC.

Also, the plugin that shaded gRPC, please let me know if you remember what plugin it was, maybe their dev team can help.

Thank you so much for taking the time! :)

[ejona86]

If IntelliJ is purposefully exposing io.grpc.Channel for plugins to use, then you shouldn't include grpc as a dependency (maybe specify it as a compileOnly dependency).

If IntelliJ is accidentally exposing io.grpc.Channel, then you should depend on gRPC but use the shadow plugin to move it to a different package name so it doesn't conflict with IntelliJ's copy. IntelliJ should also stop exposing it to your plugin.

I can't say what the expectation is from IntelliJ.

[AyushVachaspati]

I tried setting all grpc dependencies as compileOnly, and it seem to remove the classLoader issue.

val grpcVersion = "1.59.0"
val protobufVersion = "3.25.1"
val kotlinGrpcVersion = "1.4.0"

dependencies {
  compileOnly("io.grpc:grpc-netty-shaded:$grpcVersion")
  compileOnly("io.grpc:grpc-protobuf:$grpcVersion")
  compileOnly("io.grpc:grpc-stub:$grpcVersion")

  compileOnly("com.google.protobuf:protobuf-java:$protobufVersion")
  compileOnly("com.google.protobuf:protobuf-java-util:$protobufVersion")
  compileOnly("com.google.protobuf:protobuf-kotlin:$protobufVersion")
  compileOnly("io.grpc:protoc-gen-grpc-kotlin:$kotlinGrpcVersion")
}

But it caused another error

2023-11-21 10:37:51,387 [  20229] SEVERE - #c.i.o.a.i.FlushQueue - This is supposed to be overridden by subclasses.
java.lang.UnsupportedOperationException: This is supposed to be overridden by subclasses.
	at com.google.protobuf.GeneratedMessageV3.getUnknownFields(GeneratedMessageV3.java:302)
	at com.google.protobuf.TextFormat$Printer.printMessage(TextFormat.java:705)
	at com.google.protobuf.TextFormat$Printer.print(TextFormat.java:353)
	at com.google.protobuf.TextFormat$Printer.print(TextFormat.java:339)
	at com.google.protobuf.TextFormat$Printer.printToString(TextFormat.java:604)
	at com.google.protobuf.AbstractMessage.toString(AbstractMessage.java:111)
	at java.base/java.lang.String.valueOf(String.java:4218)
	at java.base/java.io.PrintStream.println(PrintStream.java:1047)

According to this thread protocolbuffers/protobuf#1206 it might be because of incompatibility between the version of my generated code, and IntelliJ's version of grpc/protobuf. Not sure how I can resolve this, or even how I can find which versions IntelliJ ships. @karollewandowski might know.

But I don't think manually matching the version is good strategy, since IntelliJ might change the version they shit in any of the future builds.

I like the idea of using shadow plugin to change the package name, but I don't know how to do that. Could you give me any reference/instructions for that. I'd really appreciate it.

Thanks!

[ejona86]

But it caused another error

I don't expect it caused it, since that's protobuf-related. I expect you got further so now you can see this additional error. So gRPC might be happy enough now.

But I don't think manually matching the version is good strategy, since IntelliJ might change the version they shit in any of the future builds.

Protobuf is compatible with older generated code. So most likely you are using a newer version of protobuf than IntelliJ. If you downgraded, and later IntelliJ upgraded, you'd be fine. But yeah, it is reasonable to just rename protobuf.

I don't know how the Gradle IntelliJ Plugin works. Apparently it is making the fat jar for you. The docs for shadow plugin describe how to rename https://imperceptiblethoughts.com/shadow/configuration/relocation/

[AyushVachaspati]

Thanks for the reference. I'm trying to configure shadowing my dependencies. But doesn't look like it's working.

tasks {
  shadowJar{
    relocate("io.grpc","shadow.io.grpc")
    relocate("com.google","shadow.com.google")
  }
}

tasks{
  buildPlugin{
    dependsOn(shadowJar)
  }
}

Not sure if this is because how IntelliJ builds the plugin, or I'm going wrong somewhere. I feel quite embarrassed that I'm not able to figure out a simple config.

I'll keep trying to make this work. I've tried to ask on the JetBrain slack as well, they'll probably be more familiar with the IntelliJ build system. Please let me know if you have any more input that might help me. I'm extremely thankful for all your help!

[ejona86]

Cross linking: https://stackoverflow.com/questions/77500782/loader-constraint-violation-for-class-io-grpc-channel-when-trying-to-create-mana

[AyushVachaspati]

Hey @ejona86
I still haven't figured out how to setup the build for IntelliJ, but Gradle Shadow plugin did generate the fat jar I wanted with plugin dependencies shadowed. So I just installed the jar manually in IntelliJ to see if it resolved the issue. I'm not getting the classLoader Error, but I do see this (not sure if classLoader thing will come back once this is fixed)

artemus.io.grpc.ManagedChannelProvider$ProviderNotFoundException: No functional channel service provider found. Try adding a dependency on the grpc-okhttp, grpc-netty, or grpc-netty-shaded artifact
	at artemus.io.grpc.ManagedChannelProvider.provider(ManagedChannelProvider.java:45)
	at artemus.io.grpc.ManagedChannelBuilder.forTarget(ManagedChannelBuilder.java:86)
        . . .

I have netty-shaded added to my dependencies, but after shadowing somehow it doesn't recognize that netty is present. Do you have any suggestions for this?

val grpcVersion = "1.59.0"
val protobufVersion = "3.25.1"
val kotlinGrpcVersion = "1.4.0"

dependencies {
  implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.6.3")
  implementation("org.jetbrains.kotlinx:kotlinx-coroutines-swing:1.6.3")
  implementation("io.grpc:grpc-netty-shaded:$grpcVersion")
  implementation("io.grpc:grpc-protobuf:$grpcVersion")
  implementation("io.grpc:grpc-stub:$grpcVersion")
  implementation("com.google.protobuf:protobuf-java:$protobufVersion")
  implementation("com.google.protobuf:protobuf-java-util:$protobufVersion")
  implementation("com.google.protobuf:protobuf-kotlin:$protobufVersion")
  implementation("io.grpc:protoc-gen-grpc-kotlin:$kotlinGrpcVersion")


tasks {
  shadowJar{
    archiveBaseName = properties("pluginName").get()
    version = properties("pluginVersion").get()
    isEnableRelocation = true
    relocationPrefix = "artemus"
  }
}

tasks{
  buildPlugin{
    dependsOn(shadowJar)
  }
}
}

I think we are very close to being able to resolve the issue, then people developing gRPC based plugins for IntelliJ can have a solid resource to tackle this problem in the future.

[ejona86]

"No functional channel service provider found" can be fixed with mergeServiceFiles(). I honestly don't understand why it isn't always enabled. There doesn't even seem to be a reason to turn it off.

[AyushVachaspati]

I added that, and got the following error.

com.intellij.diagnostic.PluginException: Cannot load class inference.GRPCInferenceServiceGrpcKt$GRPCInferenceServiceCoroutineStub (
  error: artemus/io/grpc/kotlin/AbstractCoroutineStub,
  classLoader=PluginClassLoader(plugin=PluginDescriptor(name=ArtemusAI, id=com.artemus.ArtemusAI, descriptorPath=plugin.xml, path=~\AppData\Roaming\JetBrains\IdeaIC2023.2\plugins\ArtemusAI-0.0.1-all.jar, version=0.0.1, package=null, isBundled=false), packagePrefix=null, state=active)
)
	at com.intellij.ide.plugins.cl.PluginClassLoader.loadClassInsideSelf(PluginClassLoader.kt:331)
	at com.intellij.ide.plugins.cl.PluginClassLoader.tryLoadingClass(PluginClassLoader.kt:178)
	at com.intellij.ide.plugins.cl.PluginClassLoader.loadClass(PluginClassLoader.kt:151)
	at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:520)
	at com.artemus.completionProvider.ArtemusCompletionProvider.getInlineCompletion(ArtemusCompletionProvider.kt:70)
	at com.artemus.inlineCompletionApi.InlineCompletionsManager$createPreviewInline$1.invokeSuspend(InlineCompletionsManager.kt:30)
	at artemus.kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt:33)
	at artemus.kotlinx.coroutines.DispatchedTask.run(DispatchedTask.kt:106)
	at artemus.kotlinx.coroutines.EventLoopImplBase.processNextEvent(EventLoop.common.kt:284)
	at artemus.kotlinx.coroutines.BlockingCoroutine.joinBlocking(Builders.kt:85)
	at artemus.kotlinx.coroutines.BuildersKt__BuildersKt.runBlocking(Builders.kt:59)
	at artemus.kotlinx.coroutines.BuildersKt.runBlocking(Unknown Source)
	at artemus.kotlinx.coroutines.BuildersKt__BuildersKt.runBlocking$default(Builders.kt:38)
	at artemus.kotlinx.coroutines.BuildersKt.runBlocking$default(Unknown Source)
	at com.artemus.inlineCompletionApi.InlineCompletionsManager.createPreviewInline(InlineCompletionsManager.kt:30)
	at com.artemus.inlineCompletionApi.listeners.DocumentListener.documentChangedNonBulk$lambda$2(DocumentListener.kt:78)
	at com.intellij.openapi.application.TransactionGuardImpl.runWithWritingAllowed(TransactionGuardImpl.java:208)
	at com.intellij.openapi.application.TransactionGuardImpl.access$100(TransactionGuardImpl.java:21)
	at com.intellij.openapi.application.TransactionGuardImpl$1.run(TransactionGuardImpl.java:190)
	at com.intellij.openapi.application.impl.ApplicationImpl.runIntendedWriteActionOnCurrentThread(ApplicationImpl.java:861)
	at com.intellij.openapi.application.impl.ApplicationImpl$4.run(ApplicationImpl.java:478)
	at com.intellij.openapi.application.impl.FlushQueue.doRun(FlushQueue.java:79)
	at com.intellij.openapi.application.impl.FlushQueue.runNextEvent(FlushQueue.java:121)
	at com.intellij.openapi.application.impl.FlushQueue.flushNow(FlushQueue.java:41)
	at java.desktop/java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:318)
	at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:789)
	at java.desktop/java.awt.EventQueue$3.run(EventQueue.java:740)
	at java.desktop/java.awt.EventQueue$3.run(EventQueue.java:734)
	at java.base/java.security.AccessController.doPrivileged(AccessController.java:399)
	at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:86)
	at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:759)
	at com.intellij.ide.IdeEventQueue.defaultDispatchEvent(IdeEventQueue.kt:685)
	at com.intellij.ide.IdeEventQueue._dispatchEvent$lambda$10(IdeEventQueue.kt:589)
	at com.intellij.openapi.application.impl.ApplicationImpl.runWithoutImplicitRead(ApplicationImpl.java:1485)
	at com.intellij.ide.IdeEventQueue._dispatchEvent(IdeEventQueue.kt:589)
	at com.intellij.ide.IdeEventQueue.access$_dispatchEvent(IdeEventQueue.kt:67)
	at com.intellij.ide.IdeEventQueue$dispatchEvent$processEventRunnable$1$1$1.compute(IdeEventQueue.kt:369)
	at com.intellij.ide.IdeEventQueue$dispatchEvent$processEventRunnable$1$1$1.compute(IdeEventQueue.kt:368)
	at com.intellij.openapi.progress.impl.CoreProgressManager.computePrioritized(CoreProgressManager.java:787)
	at com.intellij.ide.IdeEventQueue$dispatchEvent$processEventRunnable$1$1.invoke(IdeEventQueue.kt:368)
	at com.intellij.ide.IdeEventQueue$dispatchEvent$processEventRunnable$1$1.invoke(IdeEventQueue.kt:363)
	at com.intellij.ide.IdeEventQueueKt.performActivity$lambda$1(IdeEventQueue.kt:992)
	at com.intellij.openapi.application.TransactionGuardImpl.performActivity(TransactionGuardImpl.java:105)
	at com.intellij.ide.IdeEventQueueKt.performActivity(IdeEventQueue.kt:992)
	at com.intellij.ide.IdeEventQueue.dispatchEvent$lambda$7(IdeEventQueue.kt:363)
	at com.intellij.openapi.application.impl.ApplicationImpl.runIntendedWriteActionOnCurrentThread(ApplicationImpl.java:861)
	at com.intellij.ide.IdeEventQueue.dispatchEvent(IdeEventQueue.kt:405)
	at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:207)
	at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:128)
	at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:117)
	at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:113)
	at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:105)
	at java.desktop/java.awt.EventDispatchThread.run(EventDispatchThread.java:92)
Caused by: java.lang.NoClassDefFoundError: artemus/io/grpc/kotlin/AbstractCoroutineStub
	at java.base/java.lang.ClassLoader.defineClass2(Native Method)
	at java.base/java.lang.ClassLoader.defineClass(ClassLoader.java:1103)
	at com.intellij.util.lang.UrlClassLoader.consumeClassData(UrlClassLoader.java:268)
	at com.intellij.util.lang.ZipResourceFile.findClass(ZipResourceFile.java:113)
	at com.intellij.util.lang.JarLoader.findClass(JarLoader.java:58)
	at com.intellij.util.lang.ClassPath.findClassInLoader(ClassPath.java:238)
	at com.intellij.util.lang.ClassPath.findClass(ClassPath.java:188)
	at com.intellij.ide.plugins.cl.PluginClassLoader.loadClassInsideSelf(PluginClassLoader.kt:326)
	... 52 more
Caused by: java.lang.ClassNotFoundException: artemus.io.grpc.kotlin.AbstractCoroutineStub PluginClassLoader(plugin=PluginDescriptor(name=ArtemusAI, id=com.artemus.ArtemusAI, descriptorPath=plugin.xml, path=~\AppData\Roaming\JetBrains\IdeaIC2023.2\plugins\ArtemusAI-0.0.1-all.jar, version=0.0.1, package=null, isBundled=false), packagePrefix=null, state=active)
	at com.intellij.ide.plugins.cl.PluginClassLoader.loadClass(PluginClassLoader.kt:156)
	at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:520)
	... 60 more

Looks like I was missing grpc-kotlin-stub as a dependency. I added that and the request finally worked! :')
Thank you sooo much @ejona86 , you've been amazingly helpful. I'll try to write a proper post summarizing the entire fix, so that people in the future can also benefit.

Thanks Again!!!

[ejona86]

Glad you got it working! I'll go ahead and close this. You can post any references even with it closed.

[AyushVachaspati]

Summary Solution: https://intellij-support.jetbrains.com/hc/en-us/community/posts/15146127658002/comments/15268997066258