KTNB-1205: Support Jupyter Widgets

.editorconfig

@@ -1,5 +1,9 @@
+# noinspection EditorConfigKeyCorrectness
 [*.kt]
 ktlint_standard_filename = disabled
 
-[**/build/generated/**]
+# noinspection EditorConfigKeyCorrectness
+[**/generated/**]
 ktlint = disabled
+generated_code = true
+ij_formatter_enabled = false

README.md

@@ -12,6 +12,7 @@ Each integration lives in the `integrations/` directory and has its own README.
 - [IntelliJ Platform](integrations/intellij-platform/README.md) — interactive access to IntelliJ Platform APIs from a running IDE process.
 - [HTTP Utilities](integrations/http-util/README.md) — JSON/serialization helpers and Ktor HTTP client wrappers for notebooks.
 - [Database](integrations/database/README.md) — helpers for configuring JDBC DataSources and working with Databases.
+- [Widgets](integrations/widgets/README.md) — ipywidgets API for Kotlin notebooks.
 
 ## Contributing
 

build.gradle.kts

@@ -3,7 +3,7 @@ plugins {
     alias(libs.plugins.publisher)
     alias(libs.plugins.buildconfig)
     alias(libs.plugins.kotlin.serialization) apply false
-    alias(libs.plugins.ktlint) apply false
+    alias(libs.plugins.ktlint)
 }
 
 version =
@@ -16,6 +16,13 @@ allprojects {
     version = rootProject.version
 
     plugins.apply("org.jlleitschuh.gradle.ktlint")
+    ktlint {
+        filter {
+            exclude { entry ->
+                entry.file.toString().contains("generated")
+            }
+        }
+    }
 
     repositories {
         mavenCentral()

gradle/libs.versions.toml

@@ -3,7 +3,7 @@
 # https://intellij-support.jetbrains.com/hc/en-us/articles/206544879-Selecting-the-JDK-version-the-IDE-will-run-under
 jvmTarget = "17"
 kotlin = "2.2.20"
-kotlin-jupyter = "0.15.1-668"
+kotlin-jupyter = "0.15.3-779-1"
 publishPlugin = "2.2.0-dev-71"
 intellijPlatformGradlePlugin = "2.10.3"
 intellijPlatform = "253-EAP-SNAPSHOT" # TODO: lower to 2025.1.3 GA whenever released with required changes

integrations/intellij-platform/build.gradle.kts

@@ -12,10 +12,6 @@ plugins {
 val spaceUsername: String by properties
 val spaceToken: String by properties
 
-allprojects {
-    version = rootProject.version
-}
-
 tasks.processJupyterApiResources {
     libraryProducers = listOf("org.jetbrains.kotlinx.jupyter.intellij.IntelliJPlatformJupyterIntegration")
 }

integrations/intellij-platform/src/main/kotlin/org/jetbrains/kotlinx/jupyter/intellij/IntelliJPlatformJupyterIntegration.kt

@@ -3,7 +3,6 @@
 package org.jetbrains.kotlinx.jupyter.intellij
 
 import com.intellij.jupyter.core.executor.JupyterExecutionListener
-import com.intellij.jupyter.core.jupyter.connections.action.JupyterRestartKernelListener
 import com.intellij.jupyter.core.jupyter.connections.execution.core.JupyterNotebookSession
 import com.intellij.openapi.application.ApplicationInfo
 import com.intellij.openapi.application.ApplicationNamesInfo
@@ -48,7 +47,7 @@ class IntelliJPlatformJupyterIntegration : JupyterIntegration() {
 
             val productVersion = ApplicationInfo.getInstance().run { "$majorVersion.$minorVersion" }
             if (productVersion.toVersion() >= MINIMAL_SUPPORTED_IDE_VERSION) {
-                initializeDisposable(notebook)
+                initializeDisposable()
                 initializeIntelliJPlatformClassloader(notebook)
             } else {
                 val productName = ApplicationNamesInfo.getInstance().fullProductName
@@ -95,7 +94,7 @@ class IntelliJPlatformJupyterIntegration : JupyterIntegration() {
         }.excludeUnwantedClasspathEntries()
     }
 
-    private fun KotlinKernelHost.initializeDisposable(notebook: Notebook) {
+    private fun KotlinKernelHost.initializeDisposable() {
         fun disposeIntegration() {
             Disposer.dispose(notebookDisposable)
             displayText("IntelliJ Platform integration is disposed")
@@ -112,16 +111,6 @@ class IntelliJPlatformJupyterIntegration : JupyterIntegration() {
                 },
             )
         } catch (_: LinkageError) {
-            val topic = JupyterRestartKernelListener.TOPIC
-            requireNotNull(currentProjectFromNotebook(notebook))
-                .messageBus
-                .connect(notebookDisposable)
-                .subscribe(
-                    topic,
-                    JupyterRestartKernelListener {
-                        disposeIntegration()
-                    },
-                )
         }
     }
 

integrations/widgets/README.md

@@ -0,0 +1,46 @@
+[![JetBrains official project](https://jb.gg/badges/official.svg)](https://confluence.jetbrains.com/display/ALL/JetBrains+on+GitHub)
+[![Kotlin experimental stability](https://img.shields.io/badge/project-experimental-kotlin.svg?colorA=555555&colorB=AC29EC&label=&logo=kotlin&logoColor=ffffff&logoWidth=10)](https://kotlinlang.org/docs/components-stability.html)
+
+# Kotlin Notebook Widgets Integration
+
+This integration provides a collection of interactive widgets for Kotlin Notebooks, such as sliders, labels, and more. It allows you to create a richer, more interactive experience within your notebooks.
+
+## Usage
+
+Use this API through the `%use widgets` magic command in a Kotlin Notebook.
+
+```kotlin
+%use widgets
+
+val slider = intSliderWidget().apply {
+    min = 0
+    max = 100
+    value = 50
+    description = "Select a value:"
+}
+
+val label = labelWidget().apply {
+    value = "Current value: ${slider.value}"
+}
+
+// Display the slider
+slider
+```
+
+## Module structure
+
+This project consists of the following modules:
+
+- `widgets-api`: Contains the core widget implementations, protocols, and model definitions.
+- `widgets-jupyter`: Provides the integration logic and useful helpers for Kotlin Jupyter notebooks.
+- `widgets-generator`: Generates widget models from `schema.json`.
+- `widgets-tests`: Contains integration tests for widgets.
+
+## Development
+
+Most widgets are automatically generated from a schema.
+To regenerate widgets after changing `schema.json` or the generator itself, run:
+
+```bash
+./gradlew :integrations:widgets:widgets-generator:generateWidgets
+```

integrations/widgets/build.gradle.kts

@@ -0,0 +1,24 @@
+import org.jetbrains.kotlinx.publisher.apache2
+import org.jetbrains.kotlinx.publisher.githubRepo
+
+plugins {
+    alias(libs.plugins.publisher)
+}
+
+kotlinPublications {
+    pom {
+        githubRepo("Kotlin", "kotlin-notebook-integrations")
+        inceptionYear = "2025"
+        licenses {
+            apache2()
+        }
+        developers {
+            developer {
+                id.set("kotlin-jupyter-team")
+                name.set("Kotlin Jupyter Team")
+                organization.set("JetBrains")
+                organizationUrl.set("https://www.jetbrains.com")
+            }
+        }
+    }
+}

integrations/widgets/notebooks/output.ipynb

@@ -0,0 +1,152 @@
+{
+ "cells": [
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "id": "1dc6dfe0338edca7",
+   "metadata": {
+    "ExecuteTime": {
+     "end_time": "2026-01-16T10:53:58.196356Z",
+     "start_time": "2026-01-16T10:53:57.656370Z"
+    },
+    "executionRelatedData": {
+     "compiledClasses": [
+      "Line_3_jupyter",
+      "Line_4_jupyter",
+      "Line_5_jupyter",
+      "Line_6_jupyter",
+      "Line_7_jupyter"
+     ]
+    },
+    "tags": [
+     "skiptest"
+    ]
+   },
+   "outputs": [],
+   "source": [
+    "USE {\n",
+    "    repositories { mavenLocal() }\n",
+    "    dependencies {\n",
+    "        implementation(\"org.jetbrains.kotlinx:kotlin-jupyter-widgets-jupyter:0.3.0-1-SNAPSHOT\")\n",
+    "    }\n",
+    "}"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "id": "fc0a3dd0f8d182da",
+   "metadata": {
+    "ExecuteTime": {
+     "end_time": "2026-01-16T10:54:15.513572Z",
+     "start_time": "2026-01-16T10:54:15.442978Z"
+    },
+    "executionRelatedData": {
+     "compiledClasses": [
+      "Line_8_jupyter"
+     ]
+    }
+   },
+   "outputs": [
+    {
+     "data": {
+      "application/vnd.jupyter.widget-view+json": {
+       "model_id": "b3cd2c4b-33e9-4410-9dc4-863a95686d8b",
+       "version_major": 1,
+       "version_minor": 0
+      },
+      "text/html": [
+       "OutputModel(id=b3cd2c4b-33e9-4410-9dc4-863a95686d8b)"
+      ]
+     },
+     "metadata": {},
+     "output_type": "display_data",
+     "jetTransient": {}
+    }
+   ],
+   "source": [
+    "val out = outputWidget()\n",
+    "DISPLAY(out)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "id": "b15d36a922b1c5cf",
+   "metadata": {
+    "ExecuteTime": {
+     "end_time": "2026-01-16T10:54:41.738265Z",
+     "start_time": "2026-01-16T10:54:41.684457Z"
+    },
+    "executionRelatedData": {
+     "compiledClasses": [
+      "Line_9_jupyter"
+     ]
+    }
+   },
+   "outputs": [],
+   "source": [
+    "out.withScope {\n",
+    "    DISPLAY(\"helloo\")\n",
+    "}"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 4,
+   "id": "a44f5399f0d67f60",
+   "metadata": {
+    "ExecuteTime": {
+     "end_time": "2026-01-16T10:54:48.619173Z",
+     "start_time": "2026-01-16T10:54:48.572730Z"
+    },
+    "executionRelatedData": {
+     "compiledClasses": [
+      "Line_10_jupyter"
+     ]
+    }
+   },
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "[{output_type=display_data, data={text/plain=helloo}, metadata={}}]"
+      ]
+     },
+     "execution_count": 4,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "out.outputs"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "90094eb07622bfb5",
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Kotlin",
+   "language": "kotlin",
+   "name": "kotlin"
+  },
+  "language_info": {
+   "codemirror_mode": "text/x-kotlin",
+   "file_extension": ".kt",
+   "mimetype": "text/x-kotlin",
+   "name": "kotlin",
+   "nbconvert_exporter": "",
+   "pygments_lexer": "kotlin",
+   "version": "2.2.20"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 5
+}