[WIP] Shared core

.github/workflows/dependency-submission.yml

@@ -18,5 +18,9 @@ jobs:
         with:
           distribution: 'temurin'
           java-version: 17
+      - name: Install Rust toolchain
+        uses: actions-rust-lang/setup-rust-toolchain@v1
+        with:
+          target: wasm32-unknown-unknown
       - name: Generate and submit dependency graph
         uses: gradle/actions/dependency-submission@v4

.github/workflows/docker.yaml

@@ -32,6 +32,11 @@ jobs:
       - name: Setup Gradle
         uses: gradle/actions/setup-gradle@v4
 
+      - name: Install Rust toolchain
+        uses: actions-rust-lang/setup-rust-toolchain@v1
+        with:
+          target: wasm32-unknown-unknown
+
       - name: Log into GitHub container registry
         uses: docker/login-action@v2
         with:

.github/workflows/integration.yaml

@@ -123,6 +123,12 @@ jobs:
         if: ${{ inputs.serviceImage == '' }}
         uses: gradle/actions/setup-gradle@v4
 
+      - name: Install Rust toolchain
+        if: ${{ inputs.serviceImage == '' }}
+        uses: actions-rust-lang/setup-rust-toolchain@v1
+        with:
+          target: wasm32-unknown-unknown
+
       - name: Build restatedev/test-services-java image
         if: ${{ inputs.serviceImage == '' }}
         run: ./gradlew -Djib.console=plain :test-services:jibDockerBuild
@@ -135,7 +141,7 @@ jobs:
 
       - name: Run test tool
         continue-on-error: ${{ inputs.continueOnError == 'true' }}
-        uses: restatedev/e2e/sdk-tests@v1.0
+        uses: restatedev/e2e/sdk-tests@v2.1
         with:
           envVars: ${{ inputs.envVars }}
           testArtifactOutput: ${{ inputs.testArtifactOutput != '' && inputs.testArtifactOutput || 'sdk-java-integration-test-report' }}

.github/workflows/release-docs.yml

@@ -31,6 +31,10 @@ jobs:
           java-version: '21'
       - name: Setup Gradle
         uses: gradle/actions/setup-gradle@v4
+      - name: Install Rust toolchain
+        uses: actions-rust-lang/setup-rust-toolchain@v1
+        with:
+          target: wasm32-unknown-unknown
 
       - name: Build Javadocs
         run: gradle :sdk-aggregated-javadocs:javadoc

.github/workflows/release.yml

@@ -20,6 +20,11 @@ jobs:
       - name: Setup Gradle
         uses: gradle/actions/setup-gradle@v4
 
+      - name: Install Rust toolchain
+        uses: actions-rust-lang/setup-rust-toolchain@v1
+        with:
+          target: wasm32-unknown-unknown
+
       # Retrieve the version of the SDK
       - name: Install dasel
         run: curl -sSLf "$(curl -sSLf https://api.github.com/repos/tomwright/dasel/releases/latest | grep browser_download_url | grep linux_amd64 | grep -v .gz | cut -d\" -f 4)" -L -o dasel && chmod +x dasel && mv ./dasel /usr/local/bin/dasel

.github/workflows/tests.yml

@@ -27,6 +27,11 @@ jobs:
       - name: Setup Gradle
         uses: gradle/actions/setup-gradle@v4
 
+      - name: Install Rust toolchain
+        uses: actions-rust-lang/setup-rust-toolchain@v1
+        with:
+          target: wasm32-unknown-unknown
+
       - name: Pull Restate docker image
         run: docker pull ghcr.io/restatedev/restate:main
 
@@ -54,6 +59,10 @@ jobs:
           java-version: '21'
       - name: Setup Gradle
         uses: gradle/actions/setup-gradle@v4
+      - name: Install Rust toolchain
+        uses: actions-rust-lang/setup-rust-toolchain@v1
+        with:
+          target: wasm32-unknown-unknown
 
       - name: Build Javadocs
         run: gradle :sdk-aggregated-javadocs:javadoc

.gitignore

@@ -37,4 +37,5 @@ build
 kls_database.db
 .kotlin
 
-.restate
+.restate
+/sdk-core/src/main/rust/target/

gradle/libs.versions.toml

@@ -117,18 +117,6 @@
     [libraries.opentelemetry-kotlin.version]
       ref = 'opentelemetry'
 
-  [libraries.protobuf-java]
-    module = 'com.google.protobuf:protobuf-java'
-
-    [libraries.protobuf-java.version]
-      ref = 'protobuf'
-
-  [libraries.protobuf-kotlin]
-    module = 'com.google.protobuf:protobuf-kotlin'
-
-    [libraries.protobuf-kotlin.version]
-      ref = 'protobuf'
-
   [libraries.schema-kenerator-core]
     module = 'io.github.smiley4:schema-kenerator-core'
 
@@ -213,15 +201,39 @@
     [libraries.victools-jsonschema-module-jackson.version]
       ref = 'victools-json-schema'
 
+  [libraries.chicory-runtime]
+    module = 'com.dylibso.chicory:runtime'
+
+    [libraries.chicory-runtime.version]
+      ref = 'chicory'
+
+  [libraries.chicory-annotations]
+    module = 'com.dylibso.chicory:annotations'
+
+    [libraries.chicory-annotations.version]
+      ref = 'chicory'
+
+  [libraries.chicory-annotations-processor]
+    module = 'com.dylibso.chicory:annotations-processor'
+
+    [libraries.chicory-annotations-processor.version]
+      ref = 'chicory'
+
+  [libraries.jackson-cbor]
+    module = 'com.fasterxml.jackson.dataformat:jackson-dataformat-cbor'
+
+    [libraries.jackson-cbor.version]
+      ref = 'jackson'
+
 [plugins]
+  wasm2class = 'at.released.wasm2class.plugin:0.5.0'
   aggregate-javadoc = 'io.freefair.aggregate-javadoc:8.14'
   dependency-license-report = 'com.github.jk1.dependency-license-report:2.9'
   dokka = 'org.jetbrains.dokka:1.9.20'
   jib = 'com.google.cloud.tools.jib:3.4.5'
   jsonschema2pojo = 'org.jsonschema2pojo:1.2.2'
   nexus-publish = 'io.github.gradle-nexus.publish-plugin:1.3.0'
   openapi-generator = 'org.openapi.generator:7.17.0'
-  protobuf = 'com.google.protobuf:0.9.4'
   shadow = 'com.gradleup.shadow:9.0.0-beta8'
   spotless = 'com.diffplug.spotless:7.2.1'
   spring-dependency-management = 'io.spring.dependency-management:1.1.6'
@@ -233,14 +245,14 @@
       ref = 'ksp'
 
 [versions]
+  chicory = '1.7.5'
   jackson = '2.19.4'
   junit = '5.14.1'
   kotlinx-coroutines = '1.10.2'
   kotlinx-serialization = '1.9.0'
   ksp = '2.2.10-2.0.2'
   log4j = '2.24.3'
   opentelemetry = '1.58.0'
-  protobuf = '4.29.3'
   restate = '2.8.0-SNAPSHOT'
   schema-kenerator = '2.1.2'
   spring-boot = '3.4.13'

sdk-api-kotlin/src/main/kotlin/dev/restate/sdk/kotlin/ContextImpl.kt

@@ -123,7 +123,7 @@ internal constructor(
               )
               .await()
 
-      object : BaseInvocationHandle<Res>(handlerContext, responseSerde) {
+      object : BaseInvocationHandle<Res>(this, responseSerde) {
         override suspend fun invocationId(): String = invocationIdAsyncResult.poll().await()
       }
     }
@@ -134,7 +134,7 @@ internal constructor(
       responseTypeTag: TypeTag<Res>,
   ): InvocationHandle<Res> =
       resolveSerde<Res>(responseTypeTag).let { responseSerde ->
-        object : BaseInvocationHandle<Res>(handlerContext, responseSerde) {
+        object : BaseInvocationHandle<Res>(this, responseSerde) {
           override suspend fun invocationId(): String = invocationId
         }
       }
@@ -193,6 +193,14 @@ internal constructor(
     return AwakeableHandleImpl(this, id)
   }
 
+  override suspend fun <T : Any> signal(name: String, typeTag: TypeTag<T>): DurableFuture<T> {
+    checkNotInsideRun()
+    val serde: Serde<T> = resolveSerde(typeTag)
+    return SingleDurableFutureImpl(handlerContext.signal(name).await()).simpleMap {
+      serde.deserialize(it)
+    }
+  }
+
   override fun random(): RestateRandom {
     return this.random
   }

sdk-api-kotlin/src/main/kotlin/dev/restate/sdk/kotlin/api.kt

@@ -201,6 +201,21 @@ sealed interface Context {
    */
   fun awakeableHandle(id: String): AwakeableHandle
 
+  /**
+   * Create a [DurableFuture] waiting on a named signal targeting the current invocation.
+   *
+   * Signals are identified by `(invocationId, name)`. The resolution can arrive before or after the
+   * handler starts waiting on the signal — there's no need to pre-register.
+   *
+   * Another invocation can resolve or reject the signal using [signalHandle].
+   *
+   * @param name the signal name.
+   * @param typeTag the response type tag to use for deserializing the signal result.
+   * @return a [DurableFuture] that resolves to the signal value (or rejects with a
+   *   [dev.restate.sdk.common.TerminalException]).
+   */
+  suspend fun <T : Any> signal(name: String, typeTag: TypeTag<T>): DurableFuture<T>
+
   /**
    * Create a [RestateRandom] instance inherently predictable, seeded on the
    * [dev.restate.sdk.common.InvocationId], which is not secret.
@@ -336,6 +351,15 @@ suspend inline fun <reified T : Any> Context.awakeable(): Awakeable<T> {
   return this.awakeable(typeTag<T>())
 }
 
+/**
+ * Create a [DurableFuture] waiting on a named signal targeting the current invocation.
+ *
+ * @see Context.signal
+ */
+suspend inline fun <reified T : Any> Context.signal(name: String): DurableFuture<T> {
+  return this.signal(name, typeTag<T>())
+}
+
 /**
  * This interface can be used only within shared handlers of virtual objects. It extends [Context]
  * adding access to the virtual object instance key-value state storage.
@@ -629,6 +653,14 @@ sealed interface InvocationHandle<Res : Any?> {
 
   /** @return the output of this invocation, if present. */
   suspend fun output(): Output<Res>
+
+  /**
+   * Get a [SignalHandle] for resolving or rejecting a named signal on this invocation. The
+   * receiving handler can await on the signal using [Context.signal].
+   *
+   * @param name the signal name.
+   */
+  suspend fun signal(name: String): SignalHandle
 }
 
 /**
@@ -677,6 +709,35 @@ suspend inline fun <reified T : Any> AwakeableHandle.resolve(payload: T) {
   return this.resolve(typeTag<T>(), payload)
 }
 
+/**
+ * Handle to resolve or reject a named signal on a target invocation.
+ *
+ * Unlike awakeables, signals are identified by `(invocationId, name)` and do not need to be
+ * pre-registered: the resolution can arrive before or after the handler starts waiting.
+ */
+sealed interface SignalHandle {
+  /**
+   * Resolve the signal with the given value.
+   *
+   * @param typeTag used to serialize the result payload.
+   * @param payload the result payload.
+   */
+  suspend fun <T : Any> resolve(typeTag: TypeTag<T>, payload: T)
+
+  /**
+   * Reject the signal with the given reason. The handler awaiting the signal will receive a
+   * terminal error with [reason] as the message.
+   *
+   * @param reason the rejection reason.
+   */
+  suspend fun reject(reason: String)
+}
+
+/** Resolve the signal with the given value. */
+suspend inline fun <reified T : Any> SignalHandle.resolve(payload: T) {
+  return this.resolve(typeTag<T>(), payload)
+}
+
 /**
  * A [DurablePromise] is a durable, distributed version of a Kotlin's Deferred, or more commonly of
  * a future/promise. Restate keeps track of the [DurablePromise] across restarts/failures.
@@ -965,6 +1026,17 @@ suspend fun awakeableHandle(id: String): AwakeableHandle {
   return context().awakeableHandle(id)
 }
 
+/**
+ * Create a [DurableFuture] waiting on a named signal targeting the current invocation.
+ *
+ * @throws IllegalStateException if called outside of a Restate handler
+ * @see Context.signal
+ */
+@org.jetbrains.annotations.ApiStatus.Experimental
+suspend inline fun <reified T : Any> signal(name: String): DurableFuture<T> {
+  return context().signal(name, typeTag<T>())
+}
+
 /**
  * Get an [InvocationHandle] for an already existing invocation.
  *

sdk-api-kotlin/src/main/kotlin/dev/restate/sdk/kotlin/futures.kt

@@ -191,9 +191,12 @@ internal constructor(
 
 internal abstract class BaseInvocationHandle<Res>
 internal constructor(
-    private val handlerContext: HandlerContext,
+    private val contextImpl: ContextImpl,
     private val responseSerde: Serde<Res>,
 ) : InvocationHandle<Res> {
+  private val handlerContext: HandlerContext
+    get() = contextImpl.handlerContext
+
   override suspend fun cancel() {
     checkNotInsideRun()
     val ignored = handlerContext.cancelInvocation(invocationId()).await()
@@ -214,6 +217,11 @@ internal constructor(
         .simpleMap { it.map { responseSerde.deserialize(it) } }
         .await()
   }
+
+  override suspend fun signal(name: String): SignalHandle {
+    val resolvedId = invocationId()
+    return SignalHandleImpl(contextImpl, resolvedId, name)
+  }
 }
 
 internal class AwakeableImpl<T : Any?>
@@ -237,6 +245,24 @@ internal class AwakeableHandleImpl(val contextImpl: ContextImpl, val id: String)
   }
 }
 
+internal class SignalHandleImpl(
+    val contextImpl: ContextImpl,
+    val invocationId: String,
+    val name: String,
+) : SignalHandle {
+  override suspend fun <T : Any> resolve(typeTag: TypeTag<T>, payload: T) {
+    checkNotInsideRun()
+    contextImpl.handlerContext
+        .resolveSignal(invocationId, name, contextImpl.resolveAndSerialize(typeTag, payload))
+        .await()
+  }
+
+  override suspend fun reject(reason: String) {
+    checkNotInsideRun()
+    contextImpl.handlerContext.rejectSignal(invocationId, name, TerminalException(reason)).await()
+  }
+}
+
 internal class SelectClauseImpl<T>(override val durableFuture: DurableFuture<T>) : SelectClause<T>
 
 @PublishedApi