grpc: Splitting core module into client and server (#504)

* grpc: Split in core, client, server modules

* grpc: Add sub packages

* grpc: Move internal classes

* grpc: Update kmp example

* grpc: Reduce dependencies

* grpc: Fix Ktor server test

* grpc: Remove todo

Author: Jozott00

compiler-plugin/compiler-plugin-backend/src/main/kotlin/kotlinx/rpc/codegen/extension/RpcIrContext.kt

@@ -84,12 +84,12 @@ internal class RpcIrContext(
         if (isJvmTarget()) {
             getIrClassSymbol("io.grpc", "MethodDescriptor")
         } else {
-            getIrClassSymbol("kotlinx.rpc.grpc.internal", "MethodDescriptor")
+            getIrClassSymbol("kotlinx.rpc.grpc.descriptor", "MethodDescriptor")
         }
     }
 
     val grpcPlatformMethodType by lazy {
-        getIrClassSymbol("kotlinx.rpc.grpc.internal", "MethodType")
+        getIrClassSymbol("kotlinx.rpc.grpc.descriptor", "MethodType")
     }
 
     val grpcPlatformMethodTypeUnary by lazy {
@@ -248,7 +248,7 @@ internal class RpcIrContext(
         }
 
         val methodDescriptor by lazy {
-            namedFunction("kotlinx.rpc.grpc.internal", "methodDescriptor")
+            namedFunction("kotlinx.rpc.grpc.descriptor", "methodDescriptor")
         }
 
         val grpcServiceDescriptorDelegate by lazy {

grpc/grpc-client/build.gradle.kts

@@ -0,0 +1,32 @@
+/*
+ * Copyright 2023-2025 JetBrains s.r.o and contributors. Use of this source code is governed by the Apache 2.0 license.
+ */
+
+@file:OptIn(InternalRpcApi::class)
+
+import kotlinx.rpc.internal.InternalRpcApi
+
+plugins {
+    alias(libs.plugins.conventions.kmp)
+    alias(libs.plugins.kotlinx.rpc)
+}
+
+kotlin {
+    compilerOptions {
+        freeCompilerArgs.add("-Xexpect-actual-classes")
+    }
+
+    sourceSets {
+        commonMain {
+            dependencies {
+                api(projects.grpc.grpcCore)
+            }
+        }
+
+        nativeMain {
+            dependencies {
+                implementation(libs.atomicfu)
+            }
+        }
+    }
+}

grpc/grpc-client/gradle.properties

@@ -0,0 +1,16 @@
+#
+# Copyright 2023-2025 JetBrains s.r.o and contributors. Use of this source code is governed by the Apache 2.0 license.
+#
+kotlinx.rpc.exclude.wasmWasi=true
+kotlinx.rpc.exclude.js=true
+kotlinx.rpc.exclude.wasmJs=true
+kotlinx.rpc.exclude.mingwX64=true
+kotlinx.rpc.exclude.tvosArm64=true
+kotlinx.rpc.exclude.tvosSimulatorArm64=true
+kotlinx.rpc.exclude.tvosX64=true
+kotlinx.rpc.exclude.watchosArm32=true
+kotlinx.rpc.exclude.watchosDeviceArm64=true
+kotlinx.rpc.exclude.watchosX64=true
+# TODO: Remove once we ant to activate WatchOS (these two targets are already prepared for activation)
+kotlinx.rpc.exclude.watchosArm64=true
+kotlinx.rpc.exclude.watchosSimulatorArm64=true

grpc/grpc-core/src/commonMain/kotlin/kotlinx/rpc/grpc/ClientInterceptor.kt renamed to grpc/grpc-client/src/commonMain/kotlin/kotlinx/rpc/grpc/client/ClientInterceptor.kt

@@ -2,11 +2,13 @@
  * Copyright 2023-2025 JetBrains s.r.o and contributors. Use of this source code is governed by the Apache 2.0 license.
  */
 
-package kotlinx.rpc.grpc
+package kotlinx.rpc.grpc.client
 
 import kotlinx.coroutines.flow.Flow
-import kotlinx.rpc.grpc.internal.GrpcCallOptions
-import kotlinx.rpc.grpc.internal.MethodDescriptor
+import kotlinx.rpc.grpc.GrpcMetadata
+import kotlinx.rpc.grpc.Status
+import kotlinx.rpc.grpc.client.internal.GrpcCallOptions
+import kotlinx.rpc.grpc.descriptor.MethodDescriptor
 
 /**
  * The scope of a single outgoing gRPC client call observed by a [ClientInterceptor].
@@ -78,7 +80,7 @@ public interface ClientCallScope<Request, Response> {
      * Cancel the call locally, providing a human-readable [message] and an optional [cause].
      * This method won't return and abort all further processing.
      *
-     * We made cancel throw a [StatusException] instead of returning, so control flow is explicit and
+     * We made cancel throw a [kotlinx.rpc.grpc.StatusException] instead of returning, so control flow is explicit and
      * race conditions between interceptors and the transport layer are avoided.
      */
     public fun cancel(message: String, cause: Throwable? = null): Nothing

grpc/grpc-core/src/commonMain/kotlin/kotlinx/rpc/grpc/GrpcClient.kt renamed to grpc/grpc-client/src/commonMain/kotlin/kotlinx/rpc/grpc/client/GrpcClient.kt

@@ -2,25 +2,29 @@
  * Copyright 2023-2025 JetBrains s.r.o and contributors. Use of this source code is governed by the Apache 2.0 license.
  */
 
-package kotlinx.rpc.grpc
+package kotlinx.rpc.grpc.client
 
 import kotlinx.coroutines.flow.Flow
 import kotlinx.rpc.RpcCall
 import kotlinx.rpc.RpcClient
+import kotlinx.rpc.grpc.GrpcMetadata
+import kotlinx.rpc.grpc.client.internal.GrpcDefaultCallOptions
+import kotlinx.rpc.grpc.client.internal.ManagedChannel
+import kotlinx.rpc.grpc.client.internal.ManagedChannelBuilder
+import kotlinx.rpc.grpc.client.internal.bidirectionalStreamingRpc
+import kotlinx.rpc.grpc.client.internal.buildChannel
+import kotlinx.rpc.grpc.client.internal.clientStreamingRpc
+import kotlinx.rpc.grpc.client.internal.serverStreamingRpc
+import kotlinx.rpc.grpc.client.internal.unaryRpc
 import kotlinx.rpc.grpc.codec.EmptyMessageCodecResolver
 import kotlinx.rpc.grpc.codec.MessageCodecResolver
 import kotlinx.rpc.grpc.codec.ThrowingMessageCodecResolver
 import kotlinx.rpc.grpc.codec.plus
 import kotlinx.rpc.grpc.descriptor.GrpcServiceDelegate
 import kotlinx.rpc.grpc.descriptor.GrpcServiceDescriptor
-import kotlinx.rpc.grpc.internal.GrpcDefaultCallOptions
-import kotlinx.rpc.grpc.internal.MethodDescriptor
-import kotlinx.rpc.grpc.internal.MethodType
-import kotlinx.rpc.grpc.internal.bidirectionalStreamingRpc
-import kotlinx.rpc.grpc.internal.clientStreamingRpc
-import kotlinx.rpc.grpc.internal.serverStreamingRpc
-import kotlinx.rpc.grpc.internal.type
-import kotlinx.rpc.grpc.internal.unaryRpc
+import kotlinx.rpc.grpc.descriptor.MethodDescriptor
+import kotlinx.rpc.grpc.descriptor.MethodType
+import kotlinx.rpc.grpc.descriptor.methodType
 import kotlinx.rpc.internal.utils.map.RpcInternalConcurrentHashMap
 import kotlin.time.Duration
 
@@ -29,7 +33,7 @@ private typealias RequestClient = Any
 /**
  * GrpcClient manages gRPC communication by providing implementation for making asynchronous RPC calls.
  *
- * @field channel The [ManagedChannel] used to communicate with remote gRPC services.
+ * @field channel The [kotlinx.rpc.grpc.client.internal.ManagedChannel] used to communicate with remote gRPC services.
  */
 public class GrpcClient internal constructor(
     internal val channel: ManagedChannel,
@@ -57,7 +61,7 @@ public class GrpcClient internal constructor(
         val callOptions = GrpcDefaultCallOptions
         val trailers = GrpcMetadata()
 
-        return when (methodDescriptor.type) {
+        return when (methodDescriptor.methodType) {
             MethodType.UNARY -> unaryRpc(
                 descriptor = methodDescriptor,
                 request = request,
@@ -72,15 +76,15 @@ public class GrpcClient internal constructor(
                 trailers = trailers,
             )
 
-            else -> error("Wrong method type ${methodDescriptor.type}")
+            else -> error("Wrong method type ${methodDescriptor.methodType}")
         }
     }
 
     override fun <T> callServerStreaming(call: RpcCall): Flow<T> = withGrpcCall(call) { methodDescriptor, request ->
         val callOptions = GrpcDefaultCallOptions
         val trailers = GrpcMetadata()
 
-        when (methodDescriptor.type) {
+        when (methodDescriptor.methodType) {
             MethodType.SERVER_STREAMING -> serverStreamingRpc(
                 descriptor = methodDescriptor,
                 request = request,
@@ -95,7 +99,7 @@ public class GrpcClient internal constructor(
                 trailers = trailers,
             )
 
-            else -> error("Wrong method type ${methodDescriptor.type}")
+            else -> error("Wrong method type ${methodDescriptor.methodType}")
         }
     }
 
@@ -187,6 +191,10 @@ private fun GrpcClient(
  * Configuration class for a gRPC client, providing customization options
  * for client behavior, including interceptors, credentials, codec resolution,
  * and authority overrides.
+ *
+ * @see credentials
+ * @see overrideAuthority
+ * @see intercept
  */
 public class GrpcClientConfiguration internal constructor() {
     internal val interceptors: MutableList<ClientInterceptor> = mutableListOf()
@@ -222,6 +230,9 @@ public class GrpcClientConfiguration internal constructor() {
      *     credentials = plaintext() // for testing purposes only!
      * }
      * ```
+     *
+     * @see tls
+     * @see plaintext
      */
     public var credentials: ClientCredentials? = null
 

grpc/grpc-client/src/commonMain/kotlin/kotlinx/rpc/grpc/client/credentials.kt

@@ -0,0 +1,33 @@
+/*
+ * Copyright 2023-2025 JetBrains s.r.o and contributors. Use of this source code is governed by the Apache 2.0 license.
+ */
+
+package kotlinx.rpc.grpc.client
+
+import kotlinx.rpc.internal.utils.InternalRpcApi
+
+public expect abstract class ClientCredentials
+
+public expect class InsecureClientCredentials : ClientCredentials
+
+// we need a wrapper for InsecureChannelCredentials as our constructor would conflict with the private
+// java constructor.
+@InternalRpcApi
+public expect fun createInsecureClientCredentials(): ClientCredentials
+
+public expect class TlsClientCredentials : ClientCredentials
+
+public fun TlsClientCredentials(configure: TlsClientCredentialsBuilder.() -> Unit = {}): ClientCredentials {
+    val builder = TlsClientCredentialsBuilder()
+    builder.configure()
+    return builder.build()
+}
+
+public interface TlsClientCredentialsBuilder {
+    public fun trustManager(rootCertsPem: String): TlsClientCredentialsBuilder
+    public fun keyManager(certChainPem: String, privateKeyPem: String): TlsClientCredentialsBuilder
+}
+
+internal expect fun TlsClientCredentialsBuilder(): TlsClientCredentialsBuilder
+
+internal expect fun TlsClientCredentialsBuilder.build(): ClientCredentials

grpc/grpc-core/src/commonMain/kotlin/kotlinx/rpc/grpc/internal/ClientCall.kt renamed to grpc/grpc-client/src/commonMain/kotlin/kotlinx/rpc/grpc/client/internal/ClientCall.kt

@@ -2,7 +2,7 @@
  * Copyright 2023-2025 JetBrains s.r.o and contributors. Use of this source code is governed by the Apache 2.0 license.
  */
 
-package kotlinx.rpc.grpc.internal
+package kotlinx.rpc.grpc.client.internal
 
 import kotlinx.rpc.grpc.GrpcMetadata
 import kotlinx.rpc.grpc.Status

grpc/grpc-core/src/commonMain/kotlin/kotlinx/rpc/grpc/internal/GrpcCallOptions.kt renamed to grpc/grpc-client/src/commonMain/kotlin/kotlinx/rpc/grpc/client/internal/GrpcCallOptions.kt

@@ -2,7 +2,7 @@
  * Copyright 2023-2025 JetBrains s.r.o and contributors. Use of this source code is governed by the Apache 2.0 license.
  */
 
-package kotlinx.rpc.grpc.internal
+package kotlinx.rpc.grpc.client.internal
 
 import kotlinx.rpc.internal.utils.InternalRpcApi
 

grpc/grpc-core/src/commonMain/kotlin/kotlinx/rpc/grpc/internal/GrpcChannel.kt renamed to grpc/grpc-client/src/commonMain/kotlin/kotlinx/rpc/grpc/client/internal/GrpcChannel.kt

@@ -2,8 +2,9 @@
  * Copyright 2023-2025 JetBrains s.r.o and contributors. Use of this source code is governed by the Apache 2.0 license.
  */
 
-package kotlinx.rpc.grpc.internal
+package kotlinx.rpc.grpc.client.internal
 
+import kotlinx.rpc.grpc.descriptor.MethodDescriptor
 import kotlinx.rpc.internal.utils.InternalRpcApi
 
 @InternalRpcApi

grpc/grpc-core/src/commonMain/kotlin/kotlinx/rpc/grpc/ManagedChannel.kt renamed to grpc/grpc-client/src/commonMain/kotlin/kotlinx/rpc/grpc/client/internal/ManagedChannel.kt

@@ -4,14 +4,16 @@
 
 @file:Suppress("EXPECT_ACTUAL_CLASSIFIERS_ARE_IN_BETA_WARNING")
 
-package kotlinx.rpc.grpc
+package kotlinx.rpc.grpc.client.internal
 
-import kotlinx.rpc.grpc.internal.GrpcChannel
+import kotlinx.rpc.grpc.client.ClientCredentials
+import kotlinx.rpc.internal.utils.InternalRpcApi
 import kotlin.time.Duration
 
 /**
  * Same as [ManagedChannel], but is platform-exposed.
  */
+@InternalRpcApi
 public expect abstract class ManagedChannelPlatform : GrpcChannel
 
 /**
@@ -22,6 +24,7 @@ public expect abstract class ManagedChannelPlatform : GrpcChannel
  *
  * Provides lifecycle management.
  */
+@InternalRpcApi
 public interface ManagedChannel {
     /**
      * Returns whether the channel is shutdown.
@@ -67,19 +70,23 @@ public interface ManagedChannel {
 /**
  * Builder class for [ManagedChannel].
  */
+@InternalRpcApi
 public expect abstract class ManagedChannelBuilder<T : ManagedChannelBuilder<T>> {
     public abstract fun overrideAuthority(authority: String): T
 }
 
-internal expect fun ManagedChannelBuilder(
+@InternalRpcApi
+public expect fun ManagedChannelBuilder(
     hostname: String,
     port: Int,
     credentials: ClientCredentials? = null,
 ): ManagedChannelBuilder<*>
 
-internal expect fun ManagedChannelBuilder(
+@InternalRpcApi
+public expect fun ManagedChannelBuilder(
     target: String,
     credentials: ClientCredentials? = null,
 ): ManagedChannelBuilder<*>
 
-internal expect fun ManagedChannelBuilder<*>.buildChannel(): ManagedChannel
+@InternalRpcApi
+public expect fun ManagedChannelBuilder<*>.buildChannel(): ManagedChannel